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Automated Indexing and Tool Cleaning for Tapping

1. I Eq 8 12 b width of plate h thickness of plate Equation 9 gives the angular moment of inertia TU J 2 ro SC Eq 9 r the inner radius ry the outer radius The model used to analyze the stress is a simple point load equal to the weight of the motor rigidly attached to the motor mount a distance of half the motor length Figure 25 illustrates this model Figure 25 Illustration of the model used to analyze the stress in the motor mounts The Von Mises stress represents the maximum stress by combining all the stresses Equation 10 gives the formula for finding the Von Mises stress 1 Oym 2 01 m 05 gt 03 03 01 Eq 10 Mohr s Circle is utilized to determine the principal stresses where the principal stresses are given by Equations 11 and 12 1 1 a Eq 11 o 0 oy z 0 9y Try 2 1 1 g 5 0 ay E o el Dr Eq 12 Table 14 pg 36 gives the values used to calculate the Von Mises stress for both the X and Y axis motor mounts Table 14 Motor mount stress analysis y 47625 10 47625 103 m b 01016 _ 00099 _ m _ hb 9 525 10 9505 103 m 3A l Oym The yield strength of the aluminum plates that are being used is 250 Mpa Since 0 7403 Mpa lt 1 0728 Mpa lt lt 250 Mpa the conclusion can be made that neither the X axis nor Y axis motor mounts will fail by yielding Material and Manufacturing Process Selection We have used wrough
2. amp 2 5 A Vref 4 0 V htm aran probotix com manuals 3Axis SideStep manual htm 35 16 2010 7 32 41 PM 126 3 Axis Bi Polar Stepper Motor Driver User Manual e 2 0 Vref 3 2 V e 1 5 A Vref 2 4 V e 1 0 A Vref 1 6 V s 0 5 A Vref 0 8 V WARNING Do not exceed 4 0 V 1 Determine the step resolution you wish to use and set the dip switches according to Figure 2 2 If driving your motors at more than 1 5Amp install a BGA heatsink over the driver chip Contact us if you need heatsinks 3 Apply power 4 Connect a voltmeter between the VREF signal and GND and adjust the current trimmer to the desired voltage determined above FIGURE 2 SIDESTER ix rows Bi Polar Gtenner Mot or Driver al Fuld SLEPPEr MOL Tel uma e FULL STEP 1 4 STEP 1 8 STEP a fe 8 E v GND Vref 1 6 desired motor current o 2 5 A Vref 4 0 V o Z0A Vref 3 2V o LSA Vref 2 4 V o LOA Vref 1 6 Y 0 0 5 A Vref 0 8 Y WARNING Do not exceed 4 V HT23 260 d OPROBOTIX WARNING The SideStep has an optional on board voltage regulator section for supplying the logic side of the driver when NOT using one of our breakout boards or as a stand alone stepper motor driver JP1 must be removed when supplying the 5V lagic voltage through the IDC cable header Applying 5V through the IDC header for example when using on of our breakout boards with this jumper installed will destroy your
3. 3 tap is brushed off again 4 the tap is blown dry and any remaining debris is removed with compressed air 21 Concept 4 Vertical Brush and Reservoir 3 ra gt B ar gt lt vd lt T e bag c Figure 14 Concept 4 for the cleaning station is fixed to the table and utilizes a vertical brush and a solvent reservoir Concept 4 shown in Error Reference source not found consists of a solvent reservoir and a vertical brush The station would be fixed to one end of the table The procedure for cleaning the tap for this design would be 1 tap enters solvent 2 tap is brought into contact with brush 3 tap rotates against the brush We created three different concepts for a supercritical CO delivery system See Table 10 p 30 for the Pugh chart comparing each design and Table 9 p 29 for an outline of the advantages and disadvantages of each When formulating concepts for the supercritical CO delivery system we tried to incorporate different characteristics such as simplicity compactness the ability to be removed when not in use and to ensure that it wouldn t interfere with any other accessory attached to the machine The reason we took into account interference avoidance with the CO delivery system and not the cleaning station 1s because the delivery system must be directly underneath the tap and the cleaning station would have to be elevated to clear it This 1s not d
4. Electrical System One of the major issues currently is that we are not able to control the air solenoid used during cleaning through the Mach 3 Software This 1s because the breakout board states that 1t has a regulated 5V logic voltage but when we tested the actual voltage 1t was only 2 7 volts We had a 5V relay that would receive the signal and switch the 12V Load necessary for the solenoid but because the voltage is lower the relay is not switching Next we tried to use a MOSFET that switches between 2 0 and 4 0 volts but we still could 61 not get this to work This could be caused by incorrect wiring or by a faulty MOSFET After further research we found that MOSFETs are used mainly for switching resistive loads such as lights and if an inductive load such as a solenoid is switched it requires a diode in parallel with the solenoid to prevent the back EMFs from damaging the MOSFET Second issue that arose while testing this was that when the output that controls the solenoid is toggled the emergency state 19 activated in the software which requires a manual input to click the reset button in the software This would greatly reduce the automation of the testing process as every time the solenoid is activated to clean the tap the user will have to manually press the reset button before the process will continue Third issue is the temperature of the drivers and power supply in the enclosure We installed a cooling fan to provide air movement thr
5. WW os TE AAN E V we r d ba 7 A oy A A d N d c O i M N PART NUMBER DESCRIPTION 1 vweBaeel ICT H 3 TOLER SCIES 5 comae4 jme 2 Co2adssem TOLFA IF FER 7 woman 1 5 A a z 1 Figure 88 Assembly drawing of the supercritical CO delivery sub system 116 EEN CALA Kai i TERA NC FART HUMABER DREES ART H CHES kle T lt 0 TITI PREC Cel E TLE ARCULA MACHE EEH Z MACI Loma 1 TIO PLACE DECIMAL XCIXIS THETEPIAITEDHCPARM d 4 HATO GC TOUS PIS L8 8 S d comu SCALE TE SHEET 1 OF 1 1 3 E 2 Z Figure 89 Assembly of the X axis sub system 117 eu Case o poem A A LL 3 poe TL 5 T crear Hurt RAACH AFE IH RHE TOLERARCES PRA CTRL GRAF AR MACHI GMO TW C PUE DECBAAL THREE PLACE DECHUAAL E CES 5 E 2 Z Figure 90 Assembly of the Y axis sub system 118 DO Cos Pr 4 acalri abr oF Figure 91 Water jet cut layout 1 119 12000 m t HAVE co2 Pate 1 coz Pate 2 coz Pate X Plate 1 X Flate 2 4 Flate 3 Y Plate 3 amp uantity TITLE 1 _ waterjet4_final SEE DWG NO RE 1 A 1 SCALE 1 2 WEIGHT SHEET Lor 2 Water jet cut layout 2 Figure 92 120 APPENDIX H CIRCUIT DIAGRAM POWER LIMIT LIMIT SUPPLY 1 SWITCH SWITCH 24 VDC 65A EN L EN L BREAKOUT BOARD
6. AIR SOLENO TAP MOSFET EN Lu Figure 93 Circuit diagram 121 APPENDIX I PORT PIN LAYOUT Table 21 Port pin layout Port Pins 1 Qn l U1 B W N N 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 03xBC Signal Not in use X Step X Direction Y Step Y Direction Flood output air solenoid cleaning station Not in use Mist output air Micro Tap ZAP system foot pedal Not in use Y Limit Not in use Not in use E stop X Enable X limit Y Enable Not in use GND GND GND GND GND GND GND GND 122 APPENDIX J PURCHASED ELECTRONICS DATASHEETS Stepper motor data sheet pProboTIx UNIPOLAR RESP ONE WINDING RED A YL A au HT23 400 8 High Torque Stepper Motor 400 Ozin Hybrid Design 1 8 deg 200 Steps Per Revolution Parallel Series UniPolar Holding Torque N m 10 8 2 8 2 0 Rated Current Amps phase 4 2 2 1 3 0 Resistance ohm phase 10 0 8 0 8 1 6 Inductance mH phase 20 3 8 15 2 3 8 Rotor Inertia g cm 2 480 Motor Weight kg 2 0 Motor Length mm 112 Number of Wires 8 BIPOLAR RESP BIPOLAR SERIAL MILAN ONLY PARALLEL SO JC m 123 TORQUE Nm HT23 400 8 Torque Curve 40 TT T T T T T TORNER conetant current driver 30 J INERTIALLOAD 275gq e H ees 5 MN AAA LL LL o ES Dessen Kabes JL PEN WE HERI E MEN NUN pen a ae Lx HEN EE JL II NI HI HU i HUUT E A E
7. Fast and Slow Decay Modes 3 0 5 5 Y Logic Supply Voltage Range Home Output Synchronous Rectification for Low Power Dissipation Internal UVLO and Thermal Shutdown Circuitry Crossover Current Protection The SideStep was designed with flexibility in mind with features including LI R Internal synchronous rectification control circuitry is provided to improve power dissipation during PWM operation Internal circuit protection includes thermal shutdown with hysteresis under voltage lockout UVLO and crossover current protection Special power up sequencing is not required The logic signals are brought out to a 1 pin header on one side allowing for use of an IDC cable to connect your boards Every other pin on the IDC header is connected to ground which acts to shield the control signals from noise Noise in a stepper control system can cause miss stepping which can damage your equipment cause injury and ruin your work piece The Vref signal and HOME signals are brought out to this header to allow advanced connections to control devices such as a microcontroller which can adjust the driver s output current on the fly The dip switch can be left uninstalled or removed and wired to a microcontroller to change the step resolution mid motion for advanced speed ramping The main control signals STEP DIRECTION and ENABLE as well as a GND connection are brought out to WAGO type screw clamps for easy wiring to common dev
8. NENNEN ENNEN 123 Stepper motor datasheet 123 Bipolar stepper motor Driver kit user Manual ooonnnnnnonononononononononcnnnnnnnnnoncnonnnnnnnnnnnnnnnnnononononnononononos 125 Powersupply datas heei as 132 Breakout board datasheet tl 133 S R ST ee EE 136 VY MULT CH a TO 138 ARLENDES Sia EE 139 LIST OF TABLES Table 1 Ranked Engineering Specifications with Target Values EE 11 Table 2 Comparison of Benchmarked Products Based on Customer Requirements 12 Table 3 Morphological C T o ee 13 Tabled Motor Type Comparisons E E 25 Table Motor Type Poshie 1 a E teenie botte dad 25 Table 6 Bebesachen ic 26 Table Backlash Removal Push Bar E 27 Table 8 Advantages and Disadvantages of Each Cleaning Station esse 28 Table 9 The Advantages and Disadvantages of CO Delivery Concepts sss sese 29 Table 10 CO Deliyery System Push Chait eisir iS 30 Table 11 Cleaning Station Pugh Chart including Alpha Design sss sese sese Cy Table 12 Measurements used to determine lead screw torque esee 34 Table 15 Lead Screw torque analysis TESU Sardina 35 Table T4 Motor mount stress E 38 Table 15 Recommended operating speeds for drilling of aluminum sees 46 Table 16 Components fabricated for supercritical CO delivery eese 47 Table 17 Components fabricated for power system sese eee 48 Table 18 Components fabricated for cleaning system
9. Subtotal Total cost product Aluminum 127 34 12734 Motor and Electrical 665 34 66534 116 6 11660 112503 1125 03 CNC machine 6575 6575 hours 58 VALIDATION RESULTS As of this report preliminary testing has been completed for accuracy and the table is moving but needs to be modified The accuracy results for each axis are as follows X axis accuracy 11 5 um Y axis accuracy 104 2 um This being said both axes need to be modified to work correctly with the system Over the week between submission of this report and submission of our final prototype we will be continuing modification of the table and programming to improve the system performance In order ensure that our design will be functional and perform the way intended we will undergo validation Our planned methods for this validation are as described below Motor Testing Before we begin assembly we need to test the motors to verify that the resolution we predicted will be attainable Each motor should be able to achieve 3200 steps per revolution With this step revolution we can attain a system resolution of 0 8 um To test the motor we will be connecting to a rotary encoder with a resolution of at least 3200 counts per revolution Testing will include advancing single steps to verify that we actually see 0 1125 degrees per step We will also be testing under different speeds both starting and stopping to verify that the motor does not skip steps from f
10. eene 50 Table 19 Estimated cost for mass manufacturing of automated torque tapping test system 58 Table 20 Dill of EE ostendo ti saat meo attestato don lidad 82 Table Ee e EE E 122 LIST OF FIGURES Risute T eMC COUP AUOD Eia E E 13 Fene Gn ON Toad i ET certc M 13 Ironie EE Te E TETE 14 Piore d Servo Ni E 15 Prune Linear MOfOBO EE 15 Fisute 6 Spring and Extrusi n Mecha is 16 Poore Welle ville Wash o Dco o oda So Pee iz 16 Figure 3 Belleville Washer MegeliabIStris torte ai a 16 Figure 9 Thr st Bearing and Spring Mecha 2o ries aoro Eege Eege 17 Ficure TO Ball Screw Mie Cia E E 18 Figure 11 Concept for the cleaning station is fixed to the table and utilizes an air knife brushes sprayed solvent and adra FOE Waste dee RER 19 Figure 12 Concept 2 for the cleaning station is fixed only to the Y Axis and utilizes and air nozzle a brUsh And Ee Ne EE 20 Figure 13 Concept 3 for the cleaning station is fixed to the table and utilizes an air nozzle a age Ee RE 21 Figure 14 Concept 4 for the cleaning station is fixed to the table and utilizes a vertical brush and dsolvenb TESEV Oi 22 Figure 15 Concept 1 for the delivery system utilizes a spring thick walled tubing two collars and a TUT EE 23 Figure 16 Concept 2 for the delivery system utilizes cable ties a support rod and tubing with a oz m 23 Figure 17 Conc
11. 4 20 x 1 2 pack 100 SHCS 10 24 x 3 4 pack 100 SHCS 1 2 13 x 1 pack 10 SHCS 10 24 x 1 2 pack 100 SHCS 42 56 x 1 2 pack 100 82 Distibutor Probotix CNC4PC Probotix Probotix Newegg Grainger Radioshack Radioshack Radioshack Radioshack Radioshack Radioshack Radioshack Radioshack Radioshack McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster McMaster UY UY UN NH LE 3 8 Tube ID x 1 4 NPT Male pipe UY UN UU UY U xo 1 75 5047K17 fitting adapter McMaster 1 4 Tube OD x 1 4 NPT Male push to 8 47 5111K308 connect McMaster 1 4 Tube OD x 1 8 NPT Male push to 2 31 5111K81 connect McMaster 1 4 Tube OD x 1 4 NPT Male push to 2 31 5111K82 connect McMaster 2 23 4596K51 1 4 pipe coupling McMaster 6mm Tube OD M5x 8 Male pipe push 3 41 51115K2 to connect McMaster 3 50 6436K12 2 piece clamp on shaft collar 1 4 bore McMaster 3 66 6436K15 2 piece clamp on shaft collar 5 8 bore McMaster 10 32 91251A732 SHCS1 2 13 x 5 McMaster 6 49 92012A211 Shoulder screw 3 16 x 1 1 2 8 32 McMaster 3 63 6655K18 Thrust bearing 5 8 shaft diameter McMaster 5 83 9712K82 Belleville disc spring 630 ID McMaster 0 91 N A Tin can 3 1 x 2 Specialty Bottle Stadium 0 12 N A 3 8 ID air tubing Hardware Stadium 0 79 N A 1 4 OD air tubing Hardware 26 07 N A Electrical box Home Depot 1 77 N A
12. 60 3 The program must be able to account for table misalignment If the X and Y axes are not aligned correctly with the tap base the accuracy of the table movement will not be correct To correct for any misalignment the user will input both the characteristic center to center distance and the locations of the first and last hole The program will allow for randomization as defined by user input from a file This file must include all of the hole indices to be tested as well as a number indicating at what point in the procedure that a particular hole is to be tested The program will be able to tap at least 100 individual holes with a goal of 150 holes per test The user will be able to pause or stop the test at any time and resume testing without needing to reset the entire program The state of any given test will be monitored and recorded This will allow for multiple tests on a given bar as well as flexibility for timing errors in testing or the possibility that the tap may need to be changed mid test In the case that the test does need to be paused or stopped or if a test does not completely use an entire bar the user will be provided with both a drawing clearly showing which holes have already been tapped as well as a file that can be loaded back into the program identifying the same holes so that subsequent tests on a given bar do not repeat holes The program must communicate between the Mach3 motor controller and the WinPCA sof
13. As a result the bar is turned slightly within 5 degrees from perfectly square with respect to the table We could reaching the blocks themselves or design new risers to accept the original blocks and allow for adjustment in the Y axis direction so that any discrepancies off square can be adjusted for in the system setup The programming could be refined in the future to make 1t more user friendly including combining the setup and configuration program with the LabView program that will be running while performing a test Improvements should also include the use of dialog boxes and a custom written graphical user interface and possibly the inclusion of a function to control the motors and solenoids so that Mach the CNC program could be avoided The testing and validation of the entire setup could be refined and more closely controlled Periodic retesting for accuracy and repeatability should be done and procedures need to be developed to define the calibration to be done in the future The wiring in the enclosure currently looks like a rat s nest with wires running all over the place With additional time and a larger enclosure the wiring should be cleaned up so that if a component has to be replaced the wires can be located and connected more easily Evaluation of the cooling for the controllers and power supply could also be beneficial We need to get the solenoids and switches controlling working for air to both the Microtap machine and
14. Cleanness Strength os Number of Parts CA Curent product B Ree Auotabe Preparation time Speed of Motion Repeatability Resolution o oO d Oo Oo P oO M O O Customer Weights D E E Q O e CN t S o E uj LOCH Customer Needs Automatic Station Cleanning Ability 0 9 Jof Jalal Sweceaco 8 Ia tas 7 3 1 1 1 3 3 Simple Userimtertace 5 l _ Useren 4 IL t MimimumModfain 3 3 3 1 14 o Manual Control 6 dajaj 1 3 1 J dal B Raw score 5 B 2 N 9 e N ceo tt e Ki N N CN st CN e Ss o o o M N K o N o o o o o o C o o E o o o Y C o i e gt Es y Es a ess EE EE EE EE 3 e roo 4 E z E A E S 3 5 Technical Requriement Targets e o V BB c o dO Om SS ON cm s 5 10 7 94 19 05 67 GANTT CHART APPENDIX B l LIT ee LT LAE 0 j j TT JL WII j j j 2 ET FUTSI E I3 paraad 2d 430101 uornmodx usa sursanqe ums alg surdango Jeue FE Maloy URI aoauguuap12 JO uorgn e Az BPC muouruadx uorpayoy surunuesolg uomguojny usag po uorgrdag ug surmjagnug ad 401014 CH MALAS UISA SUE 5532014 uU Op nue uonsmboy ELISA udisaq dood eur ZH Maloy udis sur po 1d22u07 101199198 1d22u07 uormrouar 1
15. Europe El 99 1 1 normalization Figure 46 Normalized score of stainless steels 405 and martensitic 410 Land use Minerals 260 m m m num uum uum rm m nun num uum rm nu un um rm rm em rm um um rm pn uum k um m uum m on a um E R LRE 2288 X7CrAI33 405 1 X10Cr13 mart 410 1 EN Carcinogera EN Resp organics COD Resp Iinorganics E Cima change PS Rad aar GS Cuore layer E cv EE Acidification Eutrophication BEBE Lard use BS Minerals Comparing 0 318 kg XXCrAI13 405 T with 0 319 kg X10Cr13 mart 410 T Method Erc indicator 99 1 W2 02 Europe El 99 1 1 single score Figure 47 Single score comparison of stainless steels 405 and martensitic 410 Shown in figure D5 both stainless steels have approximately the same mass of raw material while martensitic 410 has 230 grams more of air pollutants Martensitic 410 has a relative higher score in respiratory organics respiratory inorganics climate change ecotoxicity acidification land use and minerals 405 has higher relative scores in carcinogens and ozone layer Based on the normalized scores shown in figure D7 the biggest environmental damage occurs to resources Environment Impact of Final Product By combining the scores of the aluminum 6060 and stainless steel 405 used in the final product it is clear that the aluminum 6060 will have a larger environmental impact This is shown by the single score of 74 aluminum of 1 8 points while the score of stainless steel 1s
16. FABRICATION PLAN eiia e E 46 Encracenno Drawno S EE 46 EE 46 S pereritic al CO de HVeEV ds bate oerte debet e heo sued eot eA Ua ao ota Lee sudo iut ua at 46 POWEE EEN 47 C Team o EE 50 ASS O 51 PAC ELOME T ss noeh testen ies Ese eu Em his uot xo ns horae uno amv ebd us won ase Ur Eoo a A 02 C Teanme Stadion THOU n coe ce o Ee 53 Supercritical CO del very Syslelitc ipe te oot ene nr ue ounce aed imi a Red ansia lad 54 boil O 56 DRE a MET M MTM RT UN 57 Cost Anal ysis Tor Mass MOTO eebe 58 VALIDATION RESULTES iii 59 NOLTE E 59 do ad A O rr dnt oL Mire Pree Ludos et en ony Me Pere desti ue Oe 59 Testine Accuracy and Repeatability geet enee ia 59 Limit Switches and Emergency Stop Button 60 FOSIE Testo da M 60 PISOGBAMNING AANDCONTROES ii ii 60 Program and Controls Specificato ds 60 Sia TE BOITE M 61 IST Se E eege 61 Mechanical EE 62 DESIGNER QUE tad lt ll DS 62 RECOMMENDATCONS 2 ati ad 64 CONCLUSTO Sis ta 64 EE 65 NEO MATION S URGE EE 65 EE o id 66 9 N SGD RIR RI ER L 0 in 67 ALLENDE ER N G e cio cio ici 68 APPENDIX C DESIGN ANAL YSIS ASSIGNMENT cunda cd do 69 APPENDIX D STEP SIZE CALC ULATION EE 77 APPENDIX E ENGINEERING CHANGES 78 APPENDIX E BILL OFMATERIA ES E 82 APPENDIX 6 ENGINEERING DRA WIN e netos eorr ia Te sul a ene ke n tob ot avra Pe dug n une etr tette ot tam r Eie Fass 84 APPENDIX T CIRCUIT DIAGRAM Espai 121 APPENDIX T PORT PINE Ol HE 122 APPENDIX J PURCHASED ELECTRONICS DATASHPREIR
17. Miners Comparing 0 558 kg ole S 6060 T with 1 61 kg GGG NiCr 1 Method EcoAndicator 99 T 42 02 Europe El 99 LT single score Figure 43 Single score comparison of aluminum 6060 and cast iron NiCr I Using Figure D2 Aluminum has relative higher scores over cast iron in the categories of carcinogens respiratory organics climate change ozone layer ecotoxicity and land use Cast iron has relative higher scores respiratory inorganics acidification and minerals Using figure D4 the breakdown of the single score that the minerals category contributes most to the score Cast iron has a point value of 6 1 compared to the point value of 1 8 for aluminum 6060 The results show that Aluminum 6060 over the lifetime of the component will have less of an environmental impact than the identical component made out of cast iron Acetone Dish The volume of material required to produce the Acetone dish is 4 06 104 5 m 3 The selected material for the acetone dish stainless steel AISI 405 is compared to stainless steel martensitic 410 to determine if one material will have less environment impact than another Using the density of the stainless steels 0 3178 kg of 405 was compared to 0 3189 kg of martensitic 410 72 1200 1 080 24 103 48 ER E AISI 405 E AISI martensitic 410 raw air water waste Figure 44 Total emissions broken down into raw material air emissions water emissions and waste for stainless steels 405 and martensiti
18. X Plate 2 was then attached to the mounting plate X plate 1 4 which provided the assembly a means to attach to the table through T slots To add strength and stability two L shaped plates X plates 3 6 were welded to the assembly After the motor and the mounting assembly were created the lead screw 3 was screwed into the table base 10 Two thrust bearing 7 were mounted onto the lead screw with a flange sandwiched in between The handle 9 with cap was mounted to the lead screw and allow for easy manual control Changes between final design and prototype The Bellville washer and the nuts were taken off 56 Y Axis 5 meae 000 3 ovem 1 s ommo E pom 0 EE 3 wem 1 s mmm A 7 wmm HC 3 sme LI 5 4 Figure 39 Assembly drawing of the Y axis lead screw 3 UNLESS OTHERW BE SPECIFIED DIMENSIONS ARE IN INCHES TOLERANCES FRACTIONAL ANGULAR MACH 4 BEND 4 TWO PLACE DECIMAL THREE PLACE DECIMAL 4 INTERPRET GEOMETRIC TOLERAH CIH G PER MATERIAL 2 yaxis SIZE DWG NO REV SCALE 1 8 WEIGHT SHEET 1 OF 1 1 Description The motor 4 was attached to the lead screw 2 through the coupler 8 and 1t was mounted to the Y plate 1 3 by four screws 7 The Y plate 1 was mounted to the table base 1 by four screws 6 as well A backlash removal consisted of a Bellville washer 10 a thrust bearing 9 and a nut 11 were mounted to the lead screw which wa
19. X inch rev the step size of a stepper motor to be Y 1 rev step and the minimum micro step coefficient to be N micro step step For current system X 0 1 in thread 0 1 inch rev a typical step size of stepper motor is Y 1 rev 200 step So the movement of the table per step D can be calculated by Eq X in O Eq C 1 The required resolution R 0 6um 2 36 x 107 in So the minimum micro step coefficient N can be calculated by R gt Eq C 2 z which gives l step 23 6 Micro Eq C 3 step N gt y O 77 APPENDIX E ENGINEERING CHANGES Change 1 The strike plate was removed to allow for supercritical of the holes in close proximity to the cleaning station The super critical CO2 delivery hinged plate would hit the strike plate before reaching the holes immediately in front of the cleaning staion IS WAS Changed by Approved by Figure 49 Removal of the strike plate Change 2 The gusset on the cleaning station mounting bracket was removed to allow for supercritical CO2 delivery of the holes in close proximity to the cleaning station The gusset was removed because it was causing more interference with the supercritical CO delivery system than the benefit of additional support IS WAS Changed by Approved by 78 Figure 50 removal of gusset from the cleaning station Change 43 The ACME nut and Belleville was not installed because of the high price of the ACME nut The addition
20. above the solvent reservoir and an air nozzle for compressed air located above the brush This design 19 unique in that it is fixed to the table only along the y axis This allows the station slide above the table when the x axis 1s moved and keeps the station in line with the tap Since the table moves a much larger distance in the x direction than in the y direction the distance the tap must travel to get to the cleaning station is greatly reduced the table must move only a few centimeters in the y direction The procedure of cleaning of the tap for this design would be 1 tap is brushed off 2 tap enters solvent 3 tap 19 brushed off again 4 the tap is blown dry and any remaining debris is removed with compressed air 20 Concept 3 Horizontal Brush and Reservoir Ge Fixed to Table e Figure 13 Concept 3 for the cleaning station is fixed to the table and utilizes an air nozzle a brush and a solvent reservoir Concept 3 shown in Error Reference source not found consists of an air nozzle for compressed air mounted to the front panel of the machine a solvent reservoir and a horizontal brush located above the solvent reservoir The cleaning station reservoir would be fixed to the table and centered along the x axis Because of this the table would have to move on both axes for the tap to reach the station The procedure for cleaning the tap for this design would be 1 tap is brushed off 2 tap enters solvent
21. com accessories htm 3 CNC Masters CNC MILLING CNC Jr Table Top Mill 20 January 2010 http www cncmasters com CNC 20Jr 20Mill htm 4 Grant Matthew Quick Start for Beginners to Drive a Stepper Motor June 2005 http www freescale com files microcontrollers doc app_note AN2974 pdf 5 Warfield Robert W Eliminating Backlash 21 January 2010 http www cnccookbook com CCBacklash1 htm 6 Levil Technology Corp LV350D series 20 January 2010 http www levil com Desktop CNC _ Milling Machines htm 7 Keling Motors http www kelinginc net 8 Byers Jerry P 2006 Metalworking Fluids CRC Press Broken Sound NY 9 Lamendola Mark How to Use Belleville Washers Correctly 01 Dec 1997 http ecmweb com mag electric_belleville_washers_correctly 10 Nice Karim How Bearings Work 15 Feb 2010 http science howstuffworks com bearing3 htm 11 Exair What is an Air Knife System 15 Feb 2010 http www exair com en US Primary 20N avigation Products Air 20Knives Pages Air 20Knives 20Home aspx 12 Oberg E Jones F Horton H Ryffel H Machinery s Handbook 27th Edition amp Guide to Machinery s Handbook pp 1023 1044 1763 Industrial Press http knovel com web portal browse display EXT KNOVEL DISPLAY bookid 1074 amp Verti callD 0 66 APPENDIX A QFD DIAGRAM System QFD Project Project 25 Automatic Tapping and Cleaning Positional Accuracy
22. decided 1t would be beneficial to include them on the table X axis limit switches Y axis limit switches Figure 30 Limit switches on the table Description The limit switches are electronic switches that shut down the movement of the motors once the switch is closed They have been placed so that the table has movement across the entire workpiece 43 Manual Operation Changes from Alpha design The x axis mechanism for manual control is has not changed from the alpha design The y axis however has been modified to simplify the manufacturing Stainless steel bar Figure 32 X Axis handle Figure 31 Y Axis handle Description The Y axis handle is made from a stainless steel flat bar a shaft collar and an extension from the original handle The extension 1s screwed into the bar The shaft collar is a two piece collar and on of the pieces was welded onto the steel bar This allows for the collar to be tightened and loosened since only the one half is welded 44 Backlash Removal Changes from Alpha design Shaft collar is used in place of the ACME nut For the Y axis a shaft collar is used in place of the ACME nut due to the high cost of the Acme nut Figure 33 Backlash reduction mechanism Description The Belleville washers are sandwiched between the shaft collar and table forcing the two away from each other This force ensures that the threads of the lead screw are always in contact with the threads of
23. design is a collection of the best features of each concept a Pugh chart was created to analyze the strengths of the alpha design against the concepts The results are shown in Table 11 p 32 31 Table 11 Cleaning Station Pugh Chart including Alpha Design Tap Cleaning E Alpha design Cost 1 a 4 The results show that the alpha design does score higher than the concepts and so adding the features of each concept did lead to an improvement in the cleaning station alpha design 0 Supercritical CO Delivery The alpha design of the supercritical CO delivery system is the same as concept above but with an additional feature of being able to be removed when it is not in use Figure 20 illustrates the final design Tap Coupling ATT RSS d u ehe J y x Nozzle Collars Mounting bracket x Figure 20 Alpha Design Supercritical CO Delivery System The system 1s made of thick walled piping that will be bent to allow the maximum distance between the nozzle and test bar to eliminate the chance of the tap hitting the nozzle during operation A threaded connector 19 put on the end of the pipe to allow the current system to connect easily When the tap is above the cleaning station the pipe is pushed through the mounting bracket when the tap is above a test hole the spring pushes the piping forward to keep the nozzle centered underneath the tap This design also 32 allows for supercritical
24. either thread forming or thread cutting taps During testing the torque needed to thread a hole is recorded by a computer program and the results can be analyzed The tapping torque test 1s the only bench scale metal cutting test available at the time Torque values are measured as a tap cuts threads into a predrilled hole in a metal specimen which can be made of various metals Test runs record average torque values and results may be expressed either as a simple torque force value or as a percent efficiency the ratio of the average torque value of a reference fluid to that of a test fluid The same tap is used on both the reference fluid and the test fluid 8 Metalworking fluids can have a significant economic and environmental impact in a manufacturing environment According to research performed by Andres Clarens a U of M Student under an EPA STAR Fellowship in 2004 metalworking fluids account for approximately 12 of manufacturing costs and can be hazardous to human health because of additives in the fluids microorganisms and biocides that can contaminate the fluids Professor Krauss group is researching ways to reduce both the cost and environmental impact of metalworking fluids Problem Description Currently between test runs the user must manually align the table to the next hole location and clean the tap to avoid cross contamination of lubricants which can affect test results The entire process needs to be automated to
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26. loop or closed User Interface Flexibility a Program Program GUL Function 1 Automate the Table amp Align Holes Accurately To drive the table the power system should have an electronic motor and corresponding transmission There are several specifications the motor should provide enough torque or force to drive the load and it should have a large enough holding torque to prevent the table from moving when the test 1s running The movement of the table needs to meet the specified accuracy precision and resolution The following section will present three possible design concepts for the power system describing each of the concepts Concept 1 Stepper Motor Figure 3 Stepper Motor A stepper motor is a brushless synchronous electric motor which rotates in discrete steps as commanded rather than rotating continuously A stepper motor can hold a load stationary when not rotating but powered The stepper motor doesn t need a feedback mechanism if the size of the motor 19 appropriately chosen so that the load doesn t exceed the holding torque However the resolution of the motor 1s usually limited by the step size of the motor 14 Concept 2 Servo Motor Figure 4 Servo Motor A servo motor will be used to provide essential torque to move the table An integral feedback device such as an encoder is attached to the motor shaft to provide the motor s actual position and velocity Thus the controller can compares the feedb
27. modifications Professor Krauss also wants to keep modifications to the current system minimal though this is a low priority eUser manual A user manual with necessary instruction is required to be provided ENGINEERING SPECIFICATIONS A Quality Function Deployment QFD chart Appendix A has been developed to interpret the customer requirements into the engineering specifications Table 1 During this process we developed the specification by taking our customer s specialized requirements into account as well as referring to some other competitive products parameters For example the engineering specification for positional accuracy 1s directly correlated to the customer requirement for precise hole alignment These specifications with the exception of the cleaning effectiveness are quantitative and measurable They are ranked based on the correlation to the customer s needs and the other specifications as well Table 1 Ranked Engineering Specifications with Target Values Engineering Specifications Tentative Target Value Units Positional Accuracy 30 0 um Resolution 0 6 um Cost lt 400 Dollar Repeatability 1 3 um Cleaning Effectiveness Qualitative N A Preparation Time 5 10 min Range 475 x 190 mm Speed of Motion 1 27 63 5 cm s Strength gt 20 Mpa Target values for positional accuracy resolution and repeatability are the minimum values to be met and based on the Microtap Autotable Because the effectivenes
28. of the Belleville washer and ACME nut would have been ineffective as the handle acts as the nut and tightens the assembly down against the bracket to prevent backlash IS WAS Changed by Approved by Figure 51 revised backlash removal in X axis Change 4 Shaft collar is used in place of the ACME nut For the Y axis a shaft collar is used in place of the ACME nut due to the high cost of the Acme nut IS WAS Changed by Approved by Figure 52 revised backlash removal in Y axis 79 Change 45 Limit switches and mechanical stops were installed to prevent damage to the system This prevents the table from moving to far in the X or Y direction which could ruin the motor mounts IS WAS Changed by Approved by Figure 53 Additon of limit switches Change 6 The hinge plate of the supercritical CO2 delivery system was shortened to prevent interference with the cleaning station IS OC WAS Cn Ch CD KL T o l T OR 7 444 1 256 Changed by Approved by Figure 54 Shortening of CO2 plate 3 by 1 4 80 Change 7 The Y axis handle was changed from one of the original handles to one that is a plate with a shaft collar welded to it This change was made because the diameter of the original handle was too large to fit unto the motor shaft IS WAS Changed by Approved by Figure 55 Change of the handle for the Y axis 81 APPENDIX F BILL OF MATERIALES Table 20 Bill of Materials Quan
29. off to prevent the interference of the cleaning station and supercritical CO2 delivery 53 Supercritical CO delivery system A e D d es OJN E sl UNLESS OTHERWISE SPECIFIED DIMENSIONS ARE IN NCHES TOLERANCES FRAC IIONAL coas SSS copo ANGULAR MACH BEND TINO PLACE DECIMAL IHRE PLACE DECIMAL O 7 ASS INTERPRET GEOMETRIC TOLERANCING PER MATERIAL E A UU e FINISH SCALE 1 8 WEIGHT SHEET OF 2 Figure 36 Assembly drawing of the supercritical CO delivery system 7 9 vI291AMO 10 912514045 5 3 Description The CO delivery system attached to the table through the same mounting plate 1 as the y axis motor does Another plate 2 screwed into the mounting plate through slots that allow for the adjustment of placement for the system The extension plate 4 was attached to plate 2 through a hinged connection 7 3 U bolts 6 were attached to the extension plate to provide a way for the CO hose to be mounted to the system Another u bolt was attached to plate 2 to provide a mounting place for a spring This spring in combination with the hinge would pull the extension plate against the alignment plate 5 when the tap is in use When the tap engages the cleaning station the system would be pushed to the side When the tap left the cleaning station the system would be realigned by the spring X Axis mo
30. pulse is 5 uS Maximum step frequency is 40 kHz You may destroy your drivers if you try to exceed 40kHz Most steppers torque really drop above 1 kHz at full step or 8 kHz if you re using the eighth step mode 131 Power supply datasheet METAPO Industrial Power Supply IM150W Series Mus CE SPECIAL FEATURES AC inputrange selected by switch High efficiency DC adjust range LED Power indicated Outpul reverses protection Free air cooling convection 199 97 50 mm Weight 0 73 kgs pcs year wananty SPECIFICATION Output DC adjustrange co ve Hold up goe ss s sc se sr 20 mes at 230Vac S0Hz seine ne c s ne ne v esc 20ms Over Voltage Protection 1 10 135 of rated output Over Power Protection 105 150 auto recovery Short Circuit Protection shut off AC recycle to restart COMECON cocco vr sr v vr ess ZP 7 5mm pitch terminal block Input Input rangae 0 132Vac 180 264Vac selected by switch Frequenocy 47 63Hz AC inrush curment Cold start 30A 1 15Vac 604 220Vac EMI RFI FCC Part 15J ClassA CISPR 22 Class A 150 Watts 10 of rating output voltage Operating temperature Ot to 40 t 10055 10t 60 50 c 60 load Storage temperature 20 t to BU c Free air cooling convection Model IM151C12 1M IM151C24 1M Output wI V1 Voltage 14 24V Max Load 12 5A 6 5A Efficiency gt 80 2115Vac 60 Hz gt 80 2 115 Va
31. summarized by Table 15 The spindle speed for drilling was determined by the machine handbook which was summarized by table 15 Table 15 Recommended operating speeds for drilling of aluminum 1 16 3 16 3000 3000 3000 46 1 4 3 8 2500 1000 1500 7 16 5 8 1500 600 750 11 16 1 1000 The components fabricated for supercritical CO delivery with corresponding tools information and operation conditions are listed in Table 16 Table 16 Components fabricated for supercritical CO delivery Oe plates CO plate2 CO plate3 Tool Info Waterjet cutter Waterjet cutter Tool Info 8 8 l6tap 0 1875 0 15 drillbit 0 1875 drill Mis Process N A fPapping Mapping Y CO2plte4 Supportblock mm Material 6061Al 2o E Qty LB 4 Mfg Process Drilling 1 end mill 0 201 1 4 Tool Info F drill bit 0 21875 0 3757 17 32 17 32 twist drill bit 0 8125 drill bit Op Condition 2500 T 3000 2500 1000 co MEE 1000 rpm Mfg Process NA Tapping lapping N A d 18 NC 7 16 14 NC 5 8 11 NC tap Tool Info Op Condition HL Ab out tap each turn Back out tap each turn Power system Aluminum components The aluminum components include the aluminum plates used as motor mounts and mechanical stops A waterjet cutter was applied to cut the aluminum plates from aluminum stock plates with sizes of 6 x 8 x 1 4 and 8 x 12 x 3 8 and a ban
32. system utilizes cable ties a support rod and tubing with a nozzle 23 Concept 2 shown in Figure 16 p 23 consists of cable ties a support rod and tubing with a nozzle The support rod is attached to the back post of the machine with cable tie The tubing 1s run along the support rod by nylon cable ties and the nozzle is pointed towards the work piece Concept 3 Verwirren CO Connection Flexible Washer CO Nozzle Figure 17 Concept 3 for the delivery system consists of two attachment brackets a mounting bracket a flexible washer and thick walled tubing Concept 3 shown in Figure 17 Concept 3 for the delivery system consists of two attachment brackets a mounting bracket a flexible washer and thick walled tubing consists of two attachment brackets a mounting bracket a flexible washer and thick walled tubing The two attachment brackets connect to the post in the back of the machine and are then connected to the mounting bracket The flexible washer is attached to the mounting bracket and the thick walled tubing is attached to the other side of the washer The CO connection is right next to the washer opposite the mounting bracket With this alignment it allows the delivery system to have a joint at the location of the flexible washer without the issue of bending the thick walled tubing The purpose of this is to allow the mechanism to be pushed out of the way of an object it comes into contact with CONCEPT EVALUA
33. that comes straight from the CO pressure tank Alignment plate gt EIE Spring mount U bolt gt Figure 28 Final design supercritical CO2 delivery system Description The delivery system consists of a spring and hinge connection The spring pulls the extension arm against an alignment plate when the tap is in use When the tap goes to the cleaning station the extension arm will be pushed out of the way After the tap is done at the cleaning station the spring will pull the extension arm back into place against the alignment plate The mounting plate connection holes are actually slot and this allows for some adjustment as to the location and height of the CO nozzle X Axis Motor Mount Changes from Alpha design The x axis motor mount is no longer made of a single block of material It now consists of four separate components which adds to the manufacturing time but it also saves in material costs c Attachment plate im Figure 29 Final design X axis motor mount Description Similarly to the alpha design the motor mount will be attached to the table through T slots The motor will be attached to a separate plate and then the two plates will be welded together To add more stability two L shaped brackets will be welded over the joint 42 Limit switches Changes from Alpha design Limit switches were not originally implemented in the Alpha design To protect both the motors and the machine itself we
34. the cleaning station so that everything will function properly The cleaning station needs to be redesigned to allow for the CO delivery system to pass under it completely and be rid of the avoidance issues that we are currently struggling with We also need to verify that the tap 1s not plunging into the middle of the brass brush in the station itself Resolution of this issue may require completely remaking the tin can currently designated to hold the brush and acetone solvent for cleaning The X axis screw needs to be re turned on the lathe so that the shaft connects with the motor and turns on center Currently machined end is off center so we will be cutting that off and replacing it with a dowel pin pressed into the screw along with Loctite in order to turn the screw on center and resolve this issue We need to standardize where and how the table will be mounted onto the base of the Microtap machine Currently we are lining it up by eye but case the table ever needs to be removed we need to define exactly where it goes so that we can use the largest possible available area allowed by table movement This attachment setup needs to be repeatable and will be outlined in the user manual to be included with the final system A repeatable way to find the hole centers needs to be developed Currently all alignment with hole centers is done by eye This could be improved by making a custom fitting that can be loaded into the machine and designed to
35. un NE E EN 500 100015002000 2500 3000 3500 400045005000 5500 60006500 70007500 8000 PULSE RATE pps H H E es 250 500 RPM t min 750 900 1200 HA AT AU Se AA AA STO 7 M i C m S EIA as r EXT AAA 124 Bipolar stepper motor Driver kit user Manual 3 Axis Bi Polar Stepper Motor Driver User Manual 3 Axis Bi Polar Stepper Motor Driver Kit User Manual Version 2 0 Model SideStep Stepper Motor Microstepping Driver Specs Chopper Current Driver J 2 2 Amp Current Limiting Dual H Bridge Configuration Full Half Quarter amp Eighth Microstepping Resolution e BV 32V Supply e Optional Integrated Charge Pump for 5V Logic Side Description The SideStep is a complete microstepping motor driver and control system with a built in translator It is designed to operate bipolar stepper motors in full half quarter and eighth step modes with output drive capability of 32 V and up to 2 5 A This driver utilizes the Allegro A3977 chip which includes a Fixed off time current regulator that has the ability to operate in slow fast or mixed decay modes This current decay control scheme results in reduced audible motor noise increased step accuracy and reduced power dissipation The SideStep is one of the smallest stepper driver boards in its class making it ideal for incorporating into robots and other industrial control equipment Bipolar Chopper Drivers Bip
36. 0 25 pts Stainless steel does however have a larger amount of raw material of 1080 g compared to 912 g of raw material in aluminum 6060 For both The resources damage category is the most important due to the fact that both aluminum and stainless steel have the highest scores in the minerals category 75 MANUFACTURING PROCESS SELECTION The purpose of our project is to aid in the research of metalworking fluids Because of this we estimate that the production volume would only be around 100 units This is a very low production volume so when determining which processes to use to manufacture the product capital investment must be very low The time it takes to manufacture each unit is not as important because with low production volumes 1t 1s usually the capital investment that dominates the cost of each unit We have determined with the aid of the Cambridge Engineering Software that 1t would be most advantageous the motor mounts be produced using 6061 aluminum as discussed above We have also determined that the solvent reservoir would best be made with AISI 405 stainless steel We have decided that 1t would be most cost effective for all aluminum parts to be created through CNC milling None of the components are that large so a relatively small mill machine would be all that is required 6060 aluminum also does not require a lot of energy to machine with respect to material removed as shown by Figure D9 Once the initial CAM files have been cr
37. 0187 drill bit M g Process Ma Tapping apping OOOO Ypltei Y table base Mechstopl Mfg Process Tapping N A Tapping Mehstop2 Mechstp3 Lead screw CW Qty NENNEN D 1 Mfg Process Tapping Tapping H Tool Info 12 32 NEF 1232 NEF NA TA te E MEME o EE IE CR G Tool Info Bandsaw Op Condition f5fUmin J _____ _ Mfg Process Drilling Tapping o Tool Info Ac drilbit 5 16418N9 Y oo Op Condition Bo0 rpm 3 Mfg Miz Process Welding Jl 49 Process Tooll o TlGweldingequpmen Op Condition _ Surfacepre cleaned ____ Cleaning station Aluminum components The aluminum components used for the cleaning station were cut by a waterjet cutter and a band saw from two stock aluminum plates with sizes of 6 x 8 x 1 4 and 8 x 12 x 3 8 Before welding the welded part must be cleaned by using acetone and a rag Then a metal wire brush was used to remove the oxides layer on the surface of the welded part to prevent contamination The filler material used in the welding was 5356 aluminum as to be compatible with the welded aluminum Then each component was drilled and tapped respectively Tin can cover In order to allow the tap to dip into the acetone stored in the reservoir a 1 diameter hole was cut out in the tin can cover by using a knife The engineering drawing will be utilized to determine the position and the size of the hole Tin can flange a
38. 1 5 amp fuses Home Depot 1 77 N A 3 amp fuses Home Depot 8 47 N A Power cord Home Depot 3 22 N A Cord connector Lowes 1 27 N A Rubber grommets Lowes 83 APPENDIX G ENGINEERING DRAWINGS AL AMGULA R MACH BPH TS PLAC Deal o THEEE PLACE RAM 4 HTIETETI G POOR EC ITEM NO PART NUMBER DESCRIPTION TAOS TM SIZE 1 DWG LK REY 1 semngpael O A S o IT 5 Z 1 Figure 56 engineering drawing of cleaning station mounting bracket assembly 84 4X R129 4 500 5 200 LA Lt AULA MACHE Bet THO PLACE CCRA THEEE PLACE DPC RAM CAME HO aningplate 4 2 2 1 Figure 57 Engineering drawing of cleaning plate 1 85 Pad ANGULAR WACHT BEHO THO PLACE CCRA T THEEE PLACE DERCRAAL HTIE 7211 Ge EC TOUS PIS 5 A a Z 1 Figure 58 Engineering drawing of cleaning plate 2 86 CL THESE PLACE DIECPAAL HATE GADE TOUS POS DES HO leaningplate DO HOF SCALE DRAH SCALE 271 L Figure 59 engineering drawing of cleaning plate 43 87 3X Q 136 LES Sech RET H PHE TOLER ACES FERLTCPA E AHALA MACHE Pet THO PLACE DELAL THEEE PLACE DECAL HATE GADE TOLA PS 5 A a z 1 Figure 60 Engineering drawing of tin can mounting bracket 88 HLESS CEHEPNEIE ECHEL CAPS RET H RHE HTIE STI GC TOLIF APA TAS POS REY 5 A a z 1 Figure 61 Engineering drawing of the brush mounting flange 89 AULA BM f TH PLACE RRAS THESE PLACE DIECPAAL HAT
39. 1000 dollar price of a single linear motor is extremely costly Table 4 Motor Type Comparison Motor Type Advantages Disadvantages Stepper Motor Provides holding torque Resolution limited by step size No feedback necessary Accuracy limited by backlash removal Relatively Inexpensive 200 few modifications Allows for manual control Servo Motor High precision Needs feedback control Reduces backlash No holding torque Allows for manual control Expensive 400 Linear Motor High precision Needs feedback mechanism Provides linear force No holding torque Needs new connection of motor and table No manual control Heavy modification Expensive 1000 Table 5 Motor Type Pugh Chart o 02 0 2 eee 25 Easy to Install Manually move po um p A A A AA Lo 1 0 2 Function 2 Backlash Removal The ideal features for backlash removal are effective compact inexpensive and robust and they should introduce less friction and provide enough holding force to ensure the mating components engage tightly Our concepts include a spring and extrusion Belleville washers thrust bearings and spring and ball screws Refer to Table 6 p 26 for advantages and disadvantages of each and Table 7 p 27 for the Pugh chart displaying how we evaluated them Spring and Extrusion Refer to Figure 6 p 16 for a picture of this concept This design only involves commonly used mechanics so it won t be costly The disadvantages of the
40. 5 Connect the power supply to the fuse and grounding block s Whack the female end off of the power cable e Strip back 2 of the outer jacket Separate the 3 wires You should have a Black L and a White N and a Green ground G e Clip back the string e Strip off 1 2 of insulation from each of those e Trim down some screw eyes so they will fit into the slots in the power supply connectors Remove the screws on the power supply connectors e Crimp on the connectors and screw them down e Plug in the power cable and verify that you have 24 Volts across V and W Then Disconnect the power cable e Crimp connectors in the same way as above to your power wires that lead to your fuse blocks and screw them down Step 6 Install the fuses in the fuse blocks bip www probotix com manuals 3Axis SideStep manual htm 5 16 2010 7 32 41 PM 130 Step 7 Connect the power and set the VREFs as described above Disconnect the power when finished Step 8 Connect the motors Step 9 Install the DB25 cable between the breakout board and your PC Step 10 Configure your software Refer to the breakout board manual for software configuration and limit and e stop wiring Step 11 Test the system with your software The SideStep is negative logic The STEP DIRECTION and ENABLE lines should be inverted in your software Please contact us if you need help configuring your software Minimum pulse width for the step
41. 6060 P with 1 51 kg GGG NI0r F Method EcoAndicator 33 T YAO Europe El 9 T T damage assessment NiCr I Iron ironmental impacts of aluminum 6060 and cast igure 41 Relative env F li IU a e E O ee MC ee HT rM ee M Me Ae eg Tux E T I I I I I I i I I I I L I I I U I 1 I I I I I L I I I I 1 I I I U I 1 I I I I I f I I I I I I L I I I I I L I I I Minerals Acicification Ecotoxicty Radiation Resp inongani Carcinogens Resp onganics B 045505 6060 1 MN S 1 Comparing 0 538 kg ale 5 6060 E with 1 61 kg GGG N10r P Method EcoAndicator 33 1 YAO Europe El 99 UT normalization NiCr I iron 6060 and cast inum Normalized score of Alum Figure 42 71 E do o es oo leo no o ii o o e iS e ii 4 4 EE E E e eee e e I I E RN ET EE DEET A ee ee ee Se ee ee Se K ee AIK ES 6060 I CExc hiCr 1 EN Carcinogers EN Resp organics E Resp inorganics MM Climate change PS Radisson MA Core layer EN Et EN Acidification Eutrophication MM Land use PS
42. Automated Indexing and Tool Cleaning for Tapping Torque Test Device Ryan Braun Yi Chen Nate Hinkle and John Prins Sponsor Gordon Krauss ME 450 Final Report Department of Mechanical Engineering University of Michigan Ann Arbor MI 48109 ME450 W10 006 Team 25 Team Tapout Instructor Katsuo Kurabayashi April 20 2010 ABSTRACT Professor Gordon Krauss is interested in testing various lubricants for metal work To do this a tapping torque tester 1s utilized The test results can possibly be extended to other metal forming operations and be used to heighten production rates We have been asked to automate this process by modifying the machine so that a software program can perform the testing with minimal operator involvement and adequate accuracy and repeatability The machine must also have the ability to clean the tap after each hole is threaded and a mount for convenient supercritical CO application EXECUTIVE SUMMARY Professor Krauss has asked us to automate a tap machine fixture table used for testing lubricants while also including a cleaning station and a mount for supercritical CO application Currently the operator must manually align each hole with the tap by sight and using a feeler gauge which is both time consuming and inaccurate The tap must also be manually cleaned after each hole is threaded so that different lubricants don t contaminate the next hole tested Automating the machine will free the operator s tim
43. Breakout Board User Manual 3 Data3 Data 3 Ha Status Register Data Register 6 Data4 In Out Data 4 Ha Control Register 16 ninitialize JL CG 2 No 17 InSelect Printer Out Ic tral 3 Yes 18 25 Ground E E z 5 Please note how they are designated inputs outputs or both Also some of them are inverted Depending on the software you choose to control it the configurations may need to be inverted on certain inputs or outputs Without going into the details just know that you may have to try different settings to get your machine to respond properly Here ts the intended and typical pinout of the PBX Z cnc interface 134 PBX 2 CNC Parallel Port Breakout Board User Manual PBX 2 CNC Interface PIHOLTS A Step X Direccion Y Step Y Drrection Z Step Z Direction A Siep A Direction E sfop Z Limit Y Limi X Limit X Enable Aus Input Y Enable Enable 1 2 3 4 5 6 H B g JU MME THE X Power Y Power Z Power A Power Input Fill upa VREG Diron GFROBOTIX Disclaimer of Liability and Accuracy Information provided by PROBOTIX is believed to be accurate and reliable However PROBOTIX assumes no responsibility for inaccuracies or omissions PROBOTIX assumes no responsibility for the use of this information and all use of such information shall be entirely at the user s own risk Life Support Policy PROBOTIX does not authorize any PROBOTIX produ
44. E CATRAL TOUS POS EnNC Jo REY tincan 1 Figure 62 Engineering drawing of the purchased acetone dish 90 UNLESS CE HEPWEE SPECIEEO DM ART I FICHES E La E m PAL ANGULAR MACHE Set mW LACE WC R i THEEE PLACE DPC RAR soe se eae E pene T EES 3 A E Z Figure 63 Engineering drawing of the acetone dish cover 91 HATE Ge EC TOUS PIS Figure 64 Engineering drawing of the acetone dish mounting flange 92 6X 8 257 5 619 4369 33597275 3 462 2 000 1 500 750 250 3 A 5 619 UNLESS LE HEE SFECTIEO DAMEHEXCHS ART H EKS eT e PRACTICONALE ANGULAR AUCH BHD E TWO PLACE DECIMAL A THREE PLACE DECRASL HTIEPST CHATA TOLIF R Fis SZE DWG NO REV co2plate Z 1 Figure 65 Engineering drawing of teh supercritical CO plate 1 93 DREES ART H HHS kle T lt 0 TA ACTORA E HATE ICAA TOUS POS DWG i s A co2plate2 5 A a z 1 Figure 66 Engineering drawing of the supercritical CO plate 2 94 amp X 257 OIMENSIOAS ARE IN CHES TOLERANCES PRACTICA ANGULAR MACH TWO PLACE D CIMA CAME IK A co2plates 5 A a z 1 Figure 67 Engineering drawing of the supercritical CO plate 3 95 CERES ART H CHES eT e Rad E ANGULAR MACHEI WD TIO PLACE DECIMAL 4 HEET PLACE DIBCIAAAL HATE ICAA TOUS POS rat A co2plate4 1 DNO HOT HALE LA 3 E 2 Z Figure 68 Engineering drawing of the super
45. ILE seo tetra Qe ced on sos theo Eege 22 Function Superenitical COP De ny TT 23 Concept ES PI OO EE 23 COMCC PED EE 23 CONCEDE ee 24 CONCEPT EVALUATION AND SELECTION sis 24 Function 1 Automate the Table amp Align Holes Accurately AA 24 SEPPE OIOI aren a o io Me du 24 SENO D ee ee Ee 25 aere A IN EE 25 Electron Backlash Te EE 26 ult E 26 Belleville T iia 26 Triste anna DAN id 26 DS e in ah cu M 26 buncton 3 Gleaming Le EE 27 Concept E Aur ERR DR 552 0 52 ere sve eset tuin Duce dus oon ao Rege zu uin DUO doe du Qo Da ac Ode Rve sau Ru cuo ET due od 27 Concept TIDE E E E pectet cae 27 Concepto Horizontal Brash and RESeETVO ii Ee 24 Concept 4 Vertical Brush and Res cr Old 28 Function Supercritical COS DEVE ii A n deat to Bde aqu 28 Concept e EE 28 Bi is A G 29 CONCEDE O N EMNI ee 29 ALPHA DESIGN DESCRIP TION E 30 MOr EEE O a eee eee eee LL ICI E Md bu Ld E 31 AA n HHT 31 Supetreritical COP DellVery TT 02 A EE 33 Backlash noO e EE CM Lise EE UM Ese utei 33 Control Mecha Moi 34 Customer Requirements and Engineering Specifications sese eee eee 34 ENGINEERING DESIGN PARAMETER ANALYSIS 34 Fead Screw Kee 34 Table Foston RESOUNO BEE 35 Ee ur EE 35 Motor Mount n aa 36 Material and Manufact ring Process Selec CLON 38 FINAE DESIGN DESCRIPTION cart sia ioi a dd 39 H teht ee E 39 ARE E a E 40 Supercritical Mr Q 41 SS A eebe E ee 42 E eebe 43 KEIER 44 AC NS T 45
46. S PRACTIONAL ANGULAR MACH BEHO E TWIOPLACEDECRAAL t THERE PLACE OBCIMAL MTR PET GAR TOLIRANCING FIR CAME HO DO HOT SCALE DEAN SCALE 122 SHEET 1 OF 1 5 A a z 1 Figure 84 Engineering drawing of the Y axis motor mount plate 1 112 pa Ta Y baa p UNLESS CY HEPMNEE SPECIFIED CREES AR H AH ACERA MATES FRACTCPSA ASGULAE MACHE Pet TH SS PLACE WC i THETEPLACEDECHEARL x MTS GC TOUS PIS CAME HO yscrew 3 A 3 Figure 85 Engineering drawing of the modified Y axis lead screw 113 UNLESS STHERWBE SPECIFIED DIMENS HS ARE IH IWS HES TOLER AHC ES TITLE FRACS TIONAL Z AH GULAR MACH BEHD 4 EE acetonetrayexpl 8 LP 3 Al 5 mean cover O 5 A 3 Figure 86 Assembly drawing of the acetone dish sub system DO HOTS CALE DRAWING SCALE 14 WEMGHT SHEET 1 OF 2 i 114 supportblockle ft cleaningplate 1 cleaningplate2 CS Back BRKT 912514540 912514196 3 deanngnates T UNLESS OTHERWISE SPECIFIED DIMENSIONS ARE IN INCHES TOLERANCES E FRACTIONAL 2 TITLE ANGULAR MACH BEND TWO PLACE DECIMAL ARS IRI MR cleaningstationexploded INTERPRET GEOMETRIC TOLERANCING PER SEE DWG NO REV FINE H A DO NOT 5 CALE DRAWING SCALE 1 4 WEIGHT SHEEL DICE 5 4 3 2 1 Figure 87 Assembly drawing of the cleaning station sub system 115 C N AE MY la l
47. TION AND SELECTION Function 1 Automate the Table amp Align Holes Accurately The power system correlates to the engineering specifications of positional accuracy resolution cost and speed of motion During the concept generation process we recognized these specifications can be decomposed into more detailed criteria to evaluate each concept These criterions include does the motor provide enough holding torque Is a feedback mechanism needed What is the cost What precision can the motor achieve Will it incorporate with the current system well Our most feasible options are stepper motors servo motors and linear motors Refer to Table 4 p 25 for advantages and disadvantages of each and Table 5 p 25 for the Pugh chart displaying how we evaluated them The following section will discuss the advantages and disadvantages of each concept in more depth Stepper motor Stepper motors provide a certain amount of holding torque which will help to lock the table when the test is running The fact that the stepper motor doesn t need a feedback mechanism will help to reduce the cost and make the installation easier Also it is easy to implement manual control to the table along with 24 stepper motors Besides the price for a typical stepper motor is about 200 dollars which is relatively inexpensive and affordable to our budget However due to its internal mechanism the stepper motor has limited step size In order to achieve the required
48. accept a hole finder similar to those commonly used on a mill in a machine shop We had talked with Sarang and Professor Krauss about including a shroud to cover the motors This shroud would be helpful for keeping the tapping oil from splashing unto the table slides lead screws and the motors Over time the tapping oil thickens up and if it gets into the slides or lead screws it will increase the torque necessary to move the table and it could reach a point where 63 torque surpasses that of the motors If the oil gets onto the motors 1t could decrease their performance as the motors are not sealed Given exposure over time the motors and related electronics could fail from build up or even exposure to the oils used during testing 12 The CO delivery system should also be re evaluated Currently we are planning on using the hose directly from the CO compressor Given more time we would like to redesign to include a jet designed for our system in order to be more accurate with the spray into each individual hole RECOMMENDATIONS Our major recommendation would be to resolve all of the issues covered in the design critique some of which we will be addressing over the next week We would advise Professor Krauss and Sarang to consult an individual more experienced in controls to explore ways to improve the programs controlling the system as well as incorporating control of the flow of supercritical CO during testing The users of this syste
49. ack signal to its programmed motion profile to alter its input signal The servo motor has no holding torque Concept 3 Linear Motor Figure 5 Linear Motor Instead of producing a torque a linear motor is an electric motor that produces a linear force along its length using electromagnets that pulse at different iterations A linear motor requires guide blocks to constrain its motion and to support a load This would force us to heavily modify the existing table in order to utilize these motors Moreover a feedback controller is necessary to provide accurate motion Like the servo motor the linear motor has no holding torque Function 2 Backlash Removal The backlash is caused by the clearance between the lead screws and the driving threads To eliminate the backlash the concept should be able to reduce the clearance between the mating components by forcing the faces of the threads of each component against each other An ideal backlash removal system will be compact and easy to install without increasing the friction in the lead screws The following section will present the design concepts for the backlash removal giving a description of each concept 15 Concept I Spring and Extrusion 2nd Nut A Spring 1st Nut al Set Screw E Figure 6 Spring and Extrusion Mechanism This anti backlash mechanism includes a spring extrusion and two nuts One nut is attached to the driving threads of the table the ot
50. and acts as a coolant and chip evacuator for the lubricant Backlash in the table is a major concern we examined the current table and took the dimension of it and then drew the CAD model to help analyze a feasible solution to remove the backlash One idea is to replace the table s current screws with ball screws 5 but this would add to the cost The most feasible design we came up with is to use a combination of Belleville washer and thrust spring The Belleville washer is a spring that applies pressure to the connection once it is clamped down with proper amount of force 9 A thrust bearing is a particular type of rotary bearing designed to support high axial load 10 To design an effective cleaning station we researched air knife system on the market Air knife systems utilize compressed air for industrial applications that include drying removing excess oils and liquids dust blow off and cooling 11 The implementation of air knife would enable the cleaning station to blow the debris on the tap thus to achieving effective cleaning To obtain the optimum machinery operation condition we looked up an online machinery hand book 12 65 REFERENCES 1 Skerlos Steven J Hayes Kim F Clarens Andres F 2008 Metal working lubricant formulations based on supercritical carbon dioxide 7414015 Patent http www freepatentsonline com 7414015 html 2 Microtap USA Inc X Y Table pdf 11 May 2009 http www threadtapping
51. application from both above and below the test bar The pipe can be rotated about the hole in the mounting bracket that 1s centered with the center of the test bar For application from the top side the pipe can be left at a slight angle to avoid interference with the tap Manual Operation The alpha design allows for manual control of the table by using a dual shaft stepper motor to drive the Y axis lead screw Figure 21 Alpha Design for Manual Operation The current system s handle can then be modified to fit onto the motor shaft Manual control of the X axis 1s accomplished by leaving one of the handles on the lead screw Since the current system has two handles for the X axis one of them can be replaced with a motor and still allow manual control with the other Backlash Removal The alpha design incorporates both thrust bearings and Belleville washers to remove backlash The design is shown in Figure 22 p 33 Figure 22 Alpha Desk Belleville washers are conical in shape and act like springs when a load is applied to them Thrust bearing support axial loads and are used in our design to be able to fully tighten the parts of the assembly without dramatically increasing the friction in turn being able to use smaller motors which will reduce cost and 33 space On the Y axis a thrust bearing 1s placed around lead screw against the table base A Belleville washer 1s then placed against the thrust bearing with a hex nut against th
52. as jejod un og eo oj paubisap st 3T 10ggsueg ul ying e uy wagas O QUOD pue JaALp JOQOW Duiddeysonimui ajajdwod e si daygogalg au r 510304 addas aulm g pue 9 G 104 Ajddns Act ADT seun uonoeJk g days paran g Suddagi pusas 3 uyubrg apend Yen In 1100353014 INDID USdO Y YNDID JOUS Suw queno dwy E amp aal quan eddo Is 15400 Duldds350 01H 103014 M de1soqoJg japon xAda350q01d 137 iagram d iring W 32018 INNOJO f A Lar 46 G EPS E HITA 2 V L a d nn bili D y d S3HOLIMS LIWN dO1S 3 YALNAWOD OL a O QquvOS 1noxvausg 138 APPENDIX K BIOS Ryan Braun Ryan is from Macomb MI and graduated from Dakota High School in 2006 He decided in high school that he was going to major in engineering and in his sophomore year at U of M chose mechanical engineering He is interested in the automotive industry and manufacturing After obtaining a Bachelor s of Science in Mechanical Engineering degree he plans on attending grad school for a master s degree but is not sure whether it will be in mechanical engineering Yi Chen Yi Chen is a student of the University of Michigan in his senior year his major is mechanical engineering He also studied at Shanghai Jiaotong University SJTU Shanghai China before he transferred to U of M He is interest in field of control and automobiles When not working he likes basketball and watching game videos Y
53. atina ll 85 Figure 58 Engineering drawing of cleaning plate EE 86 Figure 59 engineering drawing of cleaning plate 9 nan iia 87 Figure 60 Engineering drawing of tin can mounting bracket sse 88 Figure 61 Engineering drawing of the brush mounting flange esses 89 Figure 62 Engineering drawing of the purchased acetone dish sss 90 Figure 63 Engineering drawing of the acetone dish cover 91 Figure 64 Engineering drawing of the acetone dish mounting flange sees 92 Figure 65 Engineering drawing of teh supercritical CO plate S E 93 Figure 66 Engineering drawing of the supercritical CO plate H een 94 Figure 67 Engineering drawing of the supercritical CO plate H 95 Figure 68 Engineering drawing of the supercritical CO plate HA 96 Figure 69 Figure 70 Figure 71 Figure 72 Figure 73 Figure 74 Figure 75 Figure 76 Figure 77 Figure 78 Figure 79 Figure 80 Figure 81 Figure 82 Figure 83 Figure 84 Figure 85 Figure 86 Figure 87 Figure 88 Figure 89 Figure 90 Figure 91 Figure 92 Figure 93 Engineering drawing of the mechanical stop plate 1 sss 97 Engineering drawing of mechanical stop plate H 98 engineering drawing of mechanical stop 3 seen 99 Engineering drawing of the revisions needed on the slide base for limit switches 100 Engineering drawing of th
54. board and void your warranty WARNING Never remove a connection to the stepper motor with power applied There is a HIGH probability the A3977 IC will be damaged The A3977 is rated for 35V DC max The power supply voltage should be limited to 32V DC to allow for back EMF htgp www probotix com manuals 3 Axis SideStep manual htm 35 16 2010 7 32 41 PM 127 3 Axis Bi Polar Stepper Motor Driver User Manual generated by the stepper WARNING If the motor is connected during this adjustment excessive heating may occur Most motors can NOT experience temperatures above 100 C At these temperatures internal melting and seizure may occur Short term current overdrive will in general not harm most motors Motor Wiring Unipolar and Bipolar Half Coil because we re using less turns doesn t give us great low speed torque but because of the low inductance holds the torque out to high speeds TORQUE BIPOLAR Bipolar Series uses the full coil so it gives very good low speed torque But PARALLEL because of the high inductance the torque drops off rapidly Bipolar Parallel also uses the full coil so it gives good low speed performance And its low inductance allows the torque to be held out to high speeds But remember we must increase current by 40 to get those advantages UNIPOLAR E HALF COIL FEEC Holding Torque oz in Unipolar 6 Leads Tape off black and red leads OR Tape off green and blue leads Con
55. c 410 DEE EE KEE Leg KEE EE GE KEEN BEER a WEE R R d d 4 RR 4 2 RR l bBb 2 bBR I I I I I I I I I I FE Fee Se ae teuer a E ee Geert a ea a SE a EA ee A Sen SE E A geg A I eee rm E ee pm em pm ee dl n e zm rm ee pm e pm pe bm bm eee pm S re e e v en e e em em dl n e zm rm ze e zm M i SE e m s m es I CA oe rS IST DIT Ht TM m crc fco MEN I AA E aE N I E A A a a 4 I 4 4 U alla aL Carinogens Rep GTS Resp inongani dime Radiation Une beer Ecntma city Aridification Land use Mrrerais CS change BE otra 205 1 Comparing 0 318 kg SPALL 405 T with 0 319 kg X10Cr13 mart 410 T Method Erc indi BEI x10070 3 mart 410 1 or 3 1 2 02 Europe El 99 1 1 damage assessment Figure 45 Relative environmental impacts of stainless steels 405 and martensitic 410 73 Carcinogens Rep organis Resp inorgani imate Radaton Dee layer Enoboodcity Acidification cz change T Eutrophicatio EN 700413 205 1 EN vz mart 410 1 Comparing 0 318 kg XICA 405 T with 0 319 kg X10Cr13 mart 410 T Method Erc indicspor 99 T W2 02
56. c 60 Hz 132 Break out board datasheet PBX 2 CNC Parallel Port Breakout Board User Manual Parallel Port Breakout Board Version 1 0 Model PBX 2 Breakout Board Specs e DB25 Female All Pins Brought Out Jumper Enabled Input Pull up Resistors e Integrated 5V Logic Supply Regulator e PROBOTIX Pinheader amp Screw Clamp Terminals Experimental USB Powered Logic Supply The PBX 2 is a Parallel Port breakout board designed specifically for Hobby CNC machines It is compatible with a variety of Parallel Port CNC Control Software The PBxX 2 has a built in LM317 based voltage regulator section that will supply 1 5AMPS 5V to the driver outputs of this interface It also connects to the limit switch and e stop inputs through a jumper connected 1K pull up resistor network The pullup resistors are needed in most cases when switching the logic inputs through physical switches The LM317 is rated for 40VDC so you can wire it up to the same power supply as the motors You may want to run it off of a WalWart to provide an additional layer of protection and to limit noise Make sure to test the polarity of the the wires from the WalWart and make sure it is not an AC output device Any voltage between 6 and 40 volts should work The PBx 2 has an experimental USB power supply jack This Jack can supply the 5 V logic supply side of your drivers Do not plug in a USB cable without disconnecting JP6 JP6 isolates the LM317 based re
57. chmarking process two representative products analyzed were the Microtap Autotable Figure 1 p 13 and the CNC Jr Mill Figure 2 p 13 Table 2 compares each product based on the customer requirements Table 2 Comparison of Benchmarked Products Based on Customer Requirements Customer Requirements Microtap Autotable CNC Machine Precise hole alignment e Position accuracy 30um 2 5um per cm e Repeatability 1 3um 12 7um e Resolution E 0 6um S lum Automatic control of Table Yes Yes Automatic cleaning station No No Supercritical CO No No Low cost 9750 5423 User manual Yes Yes Minimum modifications N A N A Manual control option Yes Yes Torque reading ability Yes No The resolution of the Microtap Autotable 0 6um is definitely better than the standard mill 0 001 in 25 4um and is our minimum goal for resolution of our system The resolution of the CNC Jr Mill is also better than a full size CNC machine but is 8 5 times the desired resolution of the system Accuracy and resolution while dependant on the motors themselves are more variable system to system as they depend heavily on the mechanical components and characteristics of any given system lead screws backlash friction environment temperature etc Based on these facts the accuracy and repeatability of the system we design will be determined by characterization of our system Ideally repeatability would be O um and the accuracy will be equal to the system
58. critical CO plate 4 96 CAMS HO REY mechstopl 1 3 2 Z Figure 69 Engineering drawing of the mechanical stop plate 1 97 DW HO 5 A a z 1 Figure 70 Engineering drawing of mechanical stop plate 2 98 SIZE DAME NO REY Almechstop ag SHEET 1 OF 1 5 A a z 1 Figure 71 engineering drawing of mechanical stop 3 99 3 2 2 Z APPLICATION CARS SCALE HAZ SHEET 1 OF 1 1 Figure 72 Engineering drawing of the revisions needed on the slide base for limit switches 100 2 X 5 201 UNLESS CEHERPWEE SPECTIEO 2 X R21 Vi 1 l Dki NE ARTE RHE CLER HCE FRACTICIA t ANGULAR MACH BEHO TWIOPLACEDECRAAL THERE PLACE OBCIMAL PTR PST G DA Sr DO HOT SCALE DRAWER E SHEET 1 OF 1 3 2 E Z Figure 73 Engineering drawing of the left support block 101 5 000 2 X R219 0 375 DESS AET H HE TOLER Ce TER ACTORA E REY DO HOT SCALE DRANG SHEET 1 OF 1 5 A a z 1 Figure 74 Engineering drawing of the right support block 102 1 000 T T a e A MA K 4 A 5 A a z 1 Figure 75 Engineering drawing of the revisions needed on the table base for limit switches 103 UNLESS LCR HEE EE SPECIFED REY dil DO HON HALE DEAMWINCE EXSHT SHEET 1 OF 1 5 A a z 1 Figure 76 Engineering drawing of the table base revisions needed for the motor mount 104 18 750 lable Top 2 Us iul EES 1 2 A 3 Z Figure 77 Engineeri
59. ct for use in life support devices and or systems without express written approval from PROBOTIX Warrantee PROBOTIX warrants our products against defects in materials and workmanship for a period of 90 days If you discover a defect we will at our option repair or replace your product or refund your purchase price This warrantee does not cover products that have been physically abused or misused in any way Copyright 2007 PROBOTIX http www probotix com manualsPBX manual htm 3 19 2010 1 36 20 PM 135 XUOgOWd 6002 4007 1ubuAdo ABM AUPE Ul PSSNSILU 4o pasnqe A peor Ayd uaaq aAeu JEU spnpaud 5400 jou sop 3SUELIBA SY Sud Sseyaund MoA purgas 4o 3onpoud OA eaejdau 4o medal uondo Jno 3e LA aa Papp e Ia NO J SAPD 06 Jo poned E KOL OISUBUIN IOMA pue speurajetu ul 515350 jsulede sjnpoud ano SUELIBA xTLOGOHd SSgueceM wL OR Od Woy ao OG uzum ssuda Noya surms s jo pue saowap poddns ayy ur asn KOL 39npoud 4 xT1OgCO Jd Aue azuoine OU GOOD 4 XTILOSCOHd oqog odds ar EU UNO Sab au 32 Apsunus sq peus uoneuuogur ans JO asn US pue uoneuLojul siu Jo asn s 104 Aypgeuodsa ou seunsse x XLLOGCHd SUOISSILIO Jo sepeinooeut 104 Aupiqisuodssd ou sewunsse amp XxTIOSOd JAMO Agege pue azene aq oj Daat 5t XTLOGOSJ Aq pepraoad uoneunojug zAxeinaow pue Aer jo auto apow dere DU ayy buisn anoi JI ZHY 8 JO days jn ye ZHY I anoqe dop AE anbioy suaddays 50W ZH3 OF s Aousnba days WNWIXEN en sj asind dags au 104 ujpiM
60. d of mounting it to the table it will now be mounted to the height block We also will now use a purchased tin can as the reservoir this saves us money not only on material but also on manufacturing We got rid of the air knife because it was expensive and too large to be easily installed Strike plate not visible Tin can reservoir Connection Flange Figure 27 Final design cleaning station Description The new cleaning station design maintains the ability to be easily removed and cleaned The connection flange simply slides over a bracket on the mount It has a cover to minimize evaporation fumes and splash from the acetone A brass wire brush is installed inside of the reservoir to ensure that all contamination on the tap has been removed In replacement of the air knife we also have the option of using flexible nozzles to blow off the tap with compressed air No mount was needed for these since they are magnetized and can be attached anywhere on the machine We also added a strike plate to add strength where the newly designed CO delivery system will continuously come into contact with it 40 Supercritical CO Delivery Changes from Alpha design The supercritical CO delivery system was completely revamped These changes were instituted so that the CO wouldn t need to go through various connections and tubes before being applied to the work piece We instead created a mount that will hold the hose and nozzle
61. d saw was used to cut the mechanical 47 stops Then all the X plates were welded in the desired manner using tungsten inert gas TIG welding Before welding the welded part must be cleaned by using acetone and a rag Then a metal wire brush was used to remove the oxides layer on the surface of the welded part to prevent contamination The filler material used in the welding was 5356 aluminum as to be compatible with the welded aluminum After welding X plates 1 and 2 were drilled and tapped so that it can fasten to the table The Y plate and mechanical stops were drilled and tapped with appropriate drill bits and taps Since welding would inevitably lead to a certain amount of deformation to the welded components the X plates are recommended to be welded before further machining to minimize this kind of negative effect Lead screw In order to fit the motor mount the lead screw was cut by a band saw and then was turned by a lathe to get the desired diameter Table base In order to fit the Y motor mount the table base used for the Y axis lead screw was drilled using a drill press to create 4 screw holes Then those holes were tapped with the appropriate taps Y handle In order to fit the Y motor mount a new handle was made out of stainless steel The handle was first cut from a stainless steel bar and then drilled and tapped to create screw holes Then the handle was welded to a two piece shaft collar in order to allow connection to the moto
62. daauo SUNSA L WASG juam aua rn uone uto ug LH MALAS Udiso SUE You suonesosds 2Uu1u aoua uy sjuauaum boy 139110150 Josuodg un suraajq ua 68 APPENDIX C DESIGN ANALYSIS ASSIGNMENT MATERIAL SELECTION For the motor mounts and for the acetone dish a material selection process was used to find appropriate materials to use Motor mounts The function of the motor mounts is to attach the motors to the xy table so that the power generated by the motor can be transferred to the lead screw thus making the table move The objective 1s to find a material that is low cost yet has the strength to prevent deflections in the material such as bending or yielding which could cause shaft misalignment It also has to avoid twisting when the motor torque 1s applied so that the torque is fully transferred to the lead screw It also has to resist fatigue damage as it will undergo many cycles of the motor rotating and stopping It also has to resist possible corrosion due to acetone being splashed onto it Using CES EduPack 2009 the following constraints were applied Price of less than 2 USD Kg Yield strength between 100 to 500 MPa Nonflammable Excellent durability to fresh water Acceptable durability to salt water Excellent durability to weak acids Excellent durability to organic solvents Recyclable Based on these constraints and ranked from lowest to highest price Most of the materials are some alloy of aluminum The top 5 alloys a
63. design are the spring occupies too much space and it will introduce the internal friction since one lead screw will be engaged to two nuts in opposite direction Besides the stiffness of the spring needs to be carefully considered to achieve enough holding force to push the lead screw Belleville Washer Refer to Figure 7 p 16 for a picture of this concept The advantages of the Belleville washer are that they are inexpensive compact robust as well as they provide enough holding force The only drawback is that not only do they increase the internal friction the same way that spring and extrusion does but the contact surface between the washer and the table will also generate friction Thrust Bearing and Spring Refer to Figure 9 p 16 for a picture of this concept The advantage of this design 1s that the trust bearing between the spring and the table reduces the contact friction of the two However the increase in internal friction due to the engagement between the lead screw and the nuts cannot be avoided Similar as the spring and extrusion this design needs to have a carefully chosen spring so that it can provide enough holding force Also it is not as compact as the Belleville washer Ball Screw Refer to Figure 10 p 18 for a picture of this concept Due to the nature of its internal structure the ball screw has higher precision and less internal friction than a lead screw does The application of ball screw will reduce the back
64. e Y axis lead screw sse 57 Figure 40 Total emissions broken down into raw material water emissions and waste for Aluminum 6060 and Cast om Nil 70 Figure 41 Relative environmental impacts of aluminum 6060 and cast iron NiCr I 71 Figure 42 Normalized score of Aluminum 6060 and cast iron Niels 71 Figure 43 Single score comparison of aluminum 6060 and cast iron NiCr Io eee 12 Figure 44 Total emissions broken down into raw material air emissions water emissions and waste for stainless steels 405 and martensitic 410 neess 73 Figure 45 Relative environmental impacts of stainless steels 405 and martensitic 410 73 Figure 46 Normalized score of stainless steels 405 and martensitic 410 sus 74 Figure 47 Single score comparison of stainless steels 405 and martensitic 410 74 Figure 48 Aluminum 6060 requires a relatively low amount of energy to machine 76 tere Remova lor Me Strike plate 78 Figure 50 removal of gusset from the cleaning station 79 Figure Ole revised backlash ene E id 79 Figure 52 reyised backlash removalin IS ti eege 79 Ereure oo Addon Ee EE 80 Pigure 54 Shortening of CO2 plate 9 by IE nia TEENE hess 80 Figure ss Change or the handle fOr Mey E 81 Figure 56 engineering drawing of cleaning station mounting bracket assembly 84 Figures Enemeerme drawing ot eleanine plate l
65. e and ensure that undesired conditions can be reduced or eliminated The most important customer requirements are precise hole alignment automatic control of the table and an automatic cleaning station The most important engineering specifications are positional accuracy resolution and cost The alpha design has been completed on February 18 To automate the table stepper motors are utilized on each axis the control program for table movement still has to be written Precise hole alignment will be accomplished through the use of Belleville washers to remove backlash The cleaning station consists of a solvent bath air knife and brush to remove shavings and lubricant after each tapping Bent thick walled piping with a threaded connector and a nozzle on the ends will be used to deliver supercritical CO to the predrilled tap holes The final design has been completed and some changes have been made to the alpha design These changes include the computer itself can now be used as the controller with the Mach 3 software a tin can will be used in the cleaning station instead of a self manufactured solvent bath an air knife will not be used in the final design due to its high cost and difficult installation The CO delivery system has been revamped to simply be a mount for the existing hose and nozzle other changes also include the orientation and configuration of the mount motor cleaning station and supercritical CO An engineering design param
66. e left support block eee 101 Engineering drawing of the right support block un 102 Engineering drawing of the revisions needed on the table base for limit switches 103 Engineering drawing of the table base revisions needed for the motor mount 104 Engineering drawing of the revisions needed on the table top for limit switches 105 Engmeerme drawing or the Talot E EE 106 Engineering drawing of the X axis motor mount assembly sss 107 Engineering drawing of the X axis motor mount plate 1 eese 108 Engineering drawing of the X axis motor mount plate 2 sees 109 Engineering drawing of the X axis motor mount plate fi 110 Engineering drawing of the modified X axis lead ocrew sss 111 Engineering drawing of the Y axis motor mount plate Hl 112 Engineering drawing of the modified Y axis lead gcrew sess 113 Assembly drawing of the acetone dish sub system esee 114 Assembly drawing of the cleaning station sub system ees 115 Assembly drawing of the supercritical CO delivery sub system 116 Assembly Of the RETS Mne A 117 Assembly ot the Y axis sub s E 118 Lu Ee E 119 Water Jel Cue lay QUito 120 RE Sr e c AA 121 INTRODUCTION Background Professor Krauss lab group is studying lubricant effectiveness utilizing a tap torque testing machine to tap predrilled holes using
67. e possible solutions and developed concepts of ways to implement them Concepts were created for motor selection backlash reduction the cleaning station the supercritical CO delivery system and program structure Once all of the concepts were generated we ranked each concept against the others for each function The results of these rankings were organized into Pugh charts We determined that a stepper motor Belleville washer a spring loaded supercritical CO delivery system was and an open loop program were the best of the concepts The concepts for the cleaning station all rated very equally and so a combination of those ideas was eventually selected After all of the concepts for each function were ranked we proceeded to develop an alpha design This design implemented all of the best ideas from the various concepts and it was also re evaluated against the concepts to ensure that the combinations implemented in the alpha design were in fact advantageous This alpha design consists of a stepper motor a combination of thrust bearings and Belleville washers a cleaning station that utilizes an air knife and brushes that work in unison with a solvent and the spring loaded CO delivery system We analyzed the alpha design and made changes where needed This was done through both engineering analysis and reevaluating the customer s specific needs After each component was finalized we updated the engineering drawings and developed the initial fab
68. e to be done to guarantee the results The engineering specification for resolution of the alpha design is known Using the current lead screws which have a pitch of the 10 threads per inch and micro stepping to a ratio of 1 25 the resolution can be decreased to 0 508 microns which is less than the engineering specification of 0 6 microns ENGINEERING DESIGN PARAMETER ANALYSIS Lead Screw Torque To properly size the stepper motors we had to determine the torque that was necessary to turn the lead screw This was done by attaching a spring to the handle of both the X axis and Y axis table The spring was then pulled perpendicular to the moment arm and the length of the spring was measured Figure 23 Setup used to determine lead screw torque To calibrate the spring constant a weight was hung from the end of the spring and the spring length was measured The following values shown in Table 12 were collected Table 12 Measurements used to determine lead screw torque Measurement Calibration mass kg 00 7 0 3 0 Calibration length in 19 25 Moment arm in 1 375 X axis maximum deflection in 7 0 Y axis maximum deflection in Initial spring length in 34 By changing the units the spring constant was found by dividing the weight of the calibration mass by the deflection in the spring shown in Equation 1 W The weight of the calibration mass x the change in the spring length The maximum force necessary to move the hand
69. e washer By tightening the nut the screw 1s forced against the table screw threads to eliminate the backlash On the X axis a thrust bearing is placed on both sides of the X axis screw flange the Belleville washer and nut are then placed on the inside of the X axis screw flange Control Mechanism The alpha design will utilize an open loop control mechanism along with limit switches to properly identify the home position Open loop control is easily implemented with stepper motors Open loop control of stepper motors provides precise control of the position without the need for expensive sensors Customer Requirements and Engineering Specifications The alpha design meets all of the customer requirements Precise hole alignment is supported by the use of stepper motors and Belleville washers Automated control of the table is met by the use of stepper motors Automatic Tap cleaning is accomplished with the solvent bath air knife brush and stepper motors Supercritical CO lubricant delivery is accomplished by the use of the piping The cost is kept to a minimum by the use of thrust bearings and Belleville washers which will reduce the size of the motors and need for sensors Minimum modifications were accomplished by using the current system and making all the additional features bolt on Simple user interface will be accomplished through programming The alpha design theoretically meets all the engineering specifications but analysis will hav
70. eated the raw material would just have to be loaded into the machine and started by the operator A high labor commitment is not necessary and so lower labor costs would be achieved For the solvent reservoir created from AISI 405 stainless steel we have determined that sand casting would be the best way to produce this Due to the low production volume and relatively cheap cost of sand patterns the sand casting process would be cheaper than the alternatives No large machines would be needed since the metal simply needs to be melted and poured into the pattern until it solidifies It would probably though be more cost effective to buy a reservoir such as a tin can from an outside party rather than manufacturing them from a primary source There are no special steps needed in manufacturing these components such as heat treatment coatings etc nor are any of the mechanical components put under a large amount of stress Because of these circumstances the above discussed manufacturing processes would be the most ideal way to create the components R CAN ng energy per unit wt removed kcal Ib 10000 Aluminum 6061 T4 in white coventional machen A ea er xr Yield strength elastic limit ksi Figure 48 Aluminum 6060 requires a relatively low amount of energy to machine 76 APPENDIX D STEP SIZE CALCULATION Denote the thread size of lead screw to be
71. ept 3 for the delivery system consists of two attachment brackets a mounting bracket a tlexibl washer and thick walled CUDWIE cscs oes ehe Lee eu eR enee ENEE 24 Proure LS Alpha De St EE 30 Figure 19 Alpha Desten Cleaning EEN 31 Figure 20 Alpha Design Supercritical CO Delivery System eese 32 Fieure 21 Alpha Desien for Manual Operation eerste is 33 Figure 22 Alpha Desten for Backlash Removal aiii aur d de bro tug eo da ee us uiu ea Rura eue tt us Qai 33 Figure 73 setup used to determme lead Screw torque ee eege Geet reest 34 Figure 24 Torque speed curve of the implemented motor eese 36 Figure 25 Illustration of the model used to analyze the stress in the motor mounts 37 S BL 20 Dna deste Dou bc so op tata tcx dn di SEES 39 Figure 27 Pinal desien cleamme T Te EE 40 Figure 28 Final design supercritical CO2 delivery system E 41 Figure 29 Ribalsdesten Maxis Motor MOL 42 Figure Emucswitcheson the tale ai 43 PIQUE d EE 44 Pour o2 A AXIS hades 44 Eigure 99 Backlash FEC UCEOR mechani SIN T 45 Figure 34 Assembly drawing of theacetone disisi iessen eebe 52 Figure 35 Assembly drawing of the cleaning station 93 Figure 36 Assembly drawing of the supercritical CO delivery system sess 54 Figure 37 Assembly drawing of the X axis motor mount 55 Figure 38 Assembly drawing of the x axis lead screw ENEE 56 Figure 39 Assembly drawing of th
72. esirable because the machine would then have to move a considerable distance in the Z direction to use the cleaning station and from a programming stand point could become bothersome The ability to switch the application of the supercritical CO from either the top or bottom of the work piece is also desirable 22 Function 4 Supercritical CO2 Delivery Concept 1 El Springo h L KG K m amp 5 DA vk b Thick Walled Tubing Sg di Figure 15 Concept 1 for the delivery system utilizes a spring thick walled tubing two collars and a fitting for CO connection Concept 1 shown in Figure 15 Concept 1 for the delivery system utilizes a spring thick walled tubing two collars and a fitting for CO2 connection consists of a mounting bracket a spring thick walled tubing collars and a fitting for connection with the CO hose This design allows the nozzle to be flipped resulting in the application of CO to come from the top or the bottom The spring is used so that a cleaning station on the opposite end of the table can be installed Because the CO nozzle is always directly underneath the tap the spring allows for the nozzle to be pushed away from the by the cleaning station when the tap undergoes cleaning The collars are used to hold the apparatus in line so that accuracy is maintained Concept 2 Der Stange Cable Tie Support Rod 7 L EA m gt Te ca AN Figure 16 Concept 2 for the delivery
73. et cutter was applied to cut the CO plate components from two aluminum plates with sizes of o x 8 x 1 4 and 8 x 12 x 3 8 The drawing of the configuration of the two plates can be found in Appendix G Then those components were drilled with appropriate drill bit The supporting blocks and the T nuts were cut from a 2 thick 6061 aluminum block and then milled to gain the required surface finishing and other features Drilling processes were applied to create holes on the above components after that some of the holes were tapped with the required tap size Changes between final design and prototype CO plates 3 and 4 were shortened by LAT and L by band saw respectively The purpose of doing that is to prevent the spring from stretching too much and to avoid interference with the cleaning plates better During the above process the engineering drawings were referenced to determine the cutting profiles the drill and tap sizes and location of the holes The speeds and the feed rate of the milling processes were predetermined by the machinery s hand book by the equation 12 N Eq 13 T D a Where N is the spindle speed in revolutions per minute rpm V is the cutting speed in feet per minute fpm and D is the cutter diameter in inches The optimum cutting speed is 165 ft min for 6061 aluminum 1 By plugging in the diameter values of the different cutter we determined the optimum cutting speeds in rpm which is
74. eter analysis is provided to describe the approach that was used to determine the specific parameters The prototype has been finished with some changes to the design including a modification to the backlash removal the addition of limit switches and a modified Y axis handle among other things We did not achieve our desired engineering specifications and we have outlined possible modifications that could improve the overall prototype We presented the prototype at the Design Expo on April 15 and will be turning it in to our sponsor on April 27 TABLE OF CONTENTS EXECUTIVE SUMMAR Y si ll 2 INTRODUCTION 10 Ba 2 19 A OU EO ERR IUE ISO DRE RC POPSET IPOD IMPONERE 10 Problem DESC E Tt c 10 Customer LET ida 10 ENGINEERINO SPECTEICATIO NS 11 BENCHMARKING eme 12 Benchmarked Products E 12 CONC EH 0 E EE RTE 13 Function 1 Automate the Table amp Align Holes Accurately AAA 14 Concept Le EE 14 SU it A hc Graces Spes EL ostendo sc Os cance ats Sou son ome dp roten Cr o E 15 Concepto Linear NOOR oe cC cd 15 Function 2 Back lash Removal E 15 Concept T Sprino and EE EE EE Ee 16 Concept 2 Belleville Was he EE 16 Concepto Thrust Beane and SPINE iaa 17 Concept de Balb Scream arca raid 18 unci n 3 Clean Te aid 18 Concept T ur Ente and Dr ii ai 19 Concept 2 Xsaxis inde pende 20 Concepto Horizontal Br sh and Reserv O16 oio iste Eege 21 Concept Vertical Brash and ROSOEVO
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76. f 0 45 N m the motor runs at a speed of 7 250 pulses sec 35 HT23 400 8 Torque Curve TORQUE Nm 900 100015002000 2500 3000 3500 4000 4500 5000 5500 60006500 7000 7500 8000 PULSE RATE pps p MJ 250 900 RPM r min 750 900 1200 Figure 24 Torque speed curve of the implemented motor The resolution of the table positioning system is 0 79 um microstep The theoretical maximum table speed is found by multiplying the motor speed by the resolution which results in 5 73 mm s 13 54 inches min Equation 4 summarizes the table speed analysis inches Eq 4 79 um 7250 micosteps mm M AA 5 73 13 54 sec S 1 microstep Motor Mount Stress A Von Mises stress analysis was done on the motor mounts to determine the maximum stress that they would experience during operation Different stresses had to be analyzed such as the bending stress of the motor hanging from the motor mount the tensile stress of the motors weight of the mount as well as the shear stress due to the torque produced by the motor Equations 5 6 and 7 give the formula for finding these stresses Op T Eq 5 W Dr Eq 6 Txr Ea 7 T q J M Moment y Distance from the zero stress line Moment of inertia W Weight of the motor A Cross sectional area of the plate 36 T Torque r Distance from the center of the motor J Angular moment of inertia Equation 8 gives the moment of inertia for a rectangular cross section bxh
77. further changes made to the system what changes may be made in the future to improve the system and a full user manual including setup and testing procedure possible troubleshooting instructions and the description of the different programs written to control the system PROGRAMMING AND CONTROLS As of this report the programming for the system is still underway As such full documentation is not included in this document That said the following gives the requirements by which the program is being written and will be evaluated A full copy of all code written for the system will be included in the user manual to be delivered along with the final prototype on April 27 Program and Controls Specification Full testing will involve two programs written by outside sources and designed for the machinery which they are controlling An additional two programs written by our group will be controlling both of these programs to run the full system The program written by our group is being designed and written with the following specifications l The interface will be simple and user friendly and full documentation on all aspects of the custom program will be provided 2 The user will be required to define work piece characteristics including defining the hole patterns either by choosing from presets or by defining a custom pattern manually input limiting hole locations top left and bottom right most holes and cleaning station location s
78. g Process Milling Drilling Tapping TIG welding NC 6 32 NC tap rod of 5356 AI 5 Mfg Process Tool Info TIG equipment amp Filler TIG equipment amp Filler 50 jodof5356Al jodofS356Al O CSeBacksBRKT Tincancover _ Tincan flange solder alloy tin can together O O O Brisa Brash flange StrkePlte Mfg Process Tapping Soldering Tapping Soldering equipment 8 32 NC tap Tool Info 5 16 18 NC solder alloy Ider the fl in B S Op Condition Back out tap each turn solder the flange and tin can together Assembly Plan This section describes how all of the fabricated and modified components will be assembled together to form the final product Corresponding engineering drawing for the configuration is provided 51 Acetone reservoir UNLESS OTHERWBE SPECIFIED DIMENSIONS ARE IN INCHES TOLERANCES TITLE FRACTIONAL Z ANGULAR MACH BEND 4 TWO PLACE DECIMAL THREE PLACE DECIMAL 2 acetonetrayexpl INTERPRET GEO METRIC tincanflange TOLERANCIHS PER SE SEE DWG NO REV brushflange A FIN BH poworsca prawne SCALE 1 4 WEIGHT SHEET 1 OF 1 5 4 E 2 1 Figure 34 Assembly drawing of the acetone dish Description The main component of the acetone reservoir is the tin can No 1 A brush flange 3 was soldered to the inside of the tin can in order to hold the brush 4 in place The brush was attached to the brush flange by two screws The cover 5 of the tin can was placed on t
79. g and flange A nut is used to compress the spring against the flange The force of the spring then removes the clearance between the threads of the lead screw and driving nut The use of thrust bearings reduces the friction that would be experienced if the spring was in direct contact with the flange 17 Concept 4 Ball Screw Figure 10 Ball Screw Mechanism The current lead screws used in system will be replaced with appropriate sized ball screws Ball screws use ball bearings positioned between two housing that fit in the threads of the lead screw The fitting of the ball bearing in the threads removes the clearance between the flange and screw and because the balls rotate they do not wear down compared to standard ACME threads The original connecting part of the table will be redesigned to fit the ball screws Function 3 Cleaning Station We created four different concepts for a cleaning station When designing the cleaning station certain attributes such as cleaning effectiveness compactness and the ability to remove and clean the cleaning station itself all had to be considered The cleaning effectiveness is paramount so that chips or lubricant from the previously tapped hole don t contaminate future tests Secondly the station needs to be compact so that it does not physically interfere with any other moving parts or with the supercritical CO delivery system In order for the cleaning station to have a relatively long life and ma
80. gulator section from the rest of the circuit including the logic power indicator LED The USB speofication allows the USB port to draw 100mA without needing to enumerate It is very likely that your PC s USB port is protected from current overdrive Your results may vary and I assume na liability for your PC However I have been using it for quite some time on my PC It probably would not protect you from spikes so USE AT YOUR OWN RISK I would recommend driving it through an externally powered USB hub The IDC cables can supply logic side power to your driver boards Some of our drivers also have on board logic supply regulators Use the jumpers to ensure that both regulator sections are not connected at the same time The Parallel Port was primarily designed for controlling printer devices so on some pins the logic inside of the PC is inverted for different reasons The built in parallel port on your PC generally shows up at address 0x378 but that is determined by your BIOS The PBX 2 is not an isolated breakout board We strongly reccomend that you use an add on parallel port card Be aware that hose 10 MOSCHIP NM9805 Chipset driven boards will initialize at non standard addresses The Windows XP drivers will not let you change the address This is not a problem for EMC or Mach3 but currently KCam will not allow you to use a non standard parallel prot address Here is a pinout of a DB25 parallel port 133 PBX 2 CNC Parallel Port
81. her is attached only to the lead screw The extrusion is used to prevent the rotation of the nuts with each other A spring is mounted between the two nuts pushing the threads of the driving nut against the threads of the lead screw removing the clearance between the threads thus the backlash is removed This concept will introduce additional friction Concept 2 Belleville Washer Concave Feature a Belleville Washer Figure 7 Belleville Washer Figure 8 Belleville Washer Mechanism a Hs 16 A Belleville washer and a nut will be mounted to the lead screw The Belleville washer has concave feature that when compress acts like a spring The nut tightens the Belleville washer against the table housing pushing the threads between the lead screw and drive nut together This mechanics will be applied in both direction of the lead screw to ensure the backlash will be removed This concept introduces additional friction Concept 3 Thrust Bearing and Spring Thrust Beari ng Shaft Coupler Figure 9 Thrust Bearing and Spring Mechanism In this concept the backlash is removed from the Y axis by attaching a spring between the table housing and shaft collar A thrust bearing is placed between the spring and table housing to reduce the friction To remove the backlash in the X direction a spring is paced between a nut on the lead screw and the X axis screw flange and a thrust bearing is placed between the sprin
82. his is much simpler than if the tap had to spin Secondly the design is very compact This reduces the chance that it will cause interference and creates more options in terms of placement The location of the brushes is very important in this design The fact that the brushes and solvent are combined into a single cleaning stage increases the usefulness of the solvent its purpose to make debris easier to remove The residue drain is very convenient in keeping the station clean and reduces the frequency in which the station must be cleaned by the operator This design also contains many disadvantages The first 1s that the air knife increases the cost The second is that the solvent must be sprayed in Because of this some sort of pump must be used to supply the solvent In effect the concept would increase the cost number of parts and number of modifications In addition this design requires there to be three different tubes connections to supply the compressed air to the air knife the solvent to the basin and to remove the remains that fall through the drain This sort of set up can be cumbersome and inconvenient to the operator Concept 2 X axis independent This design has a few advantages The first 1s that the run time of a full test would be reduced since the table travel distance to get the tap to the cleaning station is very short Another is that the solvent reservoir can be removed which allows for convenient cleaning There are howe
83. i Chen can be reached via davidsky umich edu Nate Hinkle I grew up in the Kalamazoo area in Michigan and was homeschooled from kindergarten through all of high school I was the typical kid that loved to take apart anything I could get my hands on VCR s were my most common victims I chose mechanical engineering because it seemed to be the broadest of engineering disciplines allowing me to be able to explore many different topics and engineering approaches While graduate school is possibly a future option at the moment I am looking forward to graduating in April and moving into a full time position at that time Fun fact I am the 6 of 7 children John Prins John is originally from Holland MI graduating from Holland Christian High School Class of 2006 His interest in mechanical engineering began by the interest of the mechanical systems of cars trucks tractors and ATV s and the design of these vehicles After graduating John would like to work in the off road equipment industry and particularly in agriculture equipment After a few years of working he may return to get a masters degree in mechanical engineering 139
84. ices such as parallel port breakout boards A two stage noise filtered charge pump section is included The first stage is regulated to 12 V and has a header for a 12 V DC cooling fan The second stage drops this 12 V down to 5 V which powers the driver s logic This allows the logic supply to be driven from the same 12 24 V supply that the motor drive section is powered from The logic supply has a power on LED indicator Alternately the 12 V regulator can be left uninstalled or removed allowing separate supplies for the logic and drive sections The fan connector can be used for the power supply input Both regulator sections can be left uninstalled or removed to allow a single logic supply to be fed to the driver through the IDC pin header such as from our PBX 1 breakout board with integrated charge pump Additionally the 5 V pin on the pinheader can be used to feed other boards from a single board or to feed pull up resistors for limit and home switches provided that the current limits of the 7805 regulator are not exceeded An 8 pin SIP resistor acts as the pull ups for the logic signals The eighth pin acts as a bridge in the event that your application requires reversed logic to the step and direction signals Simply cut aff the necessary pin s fram the SIP resistor before installing A provision for an inline resistor and a decoupling capacitor has been included for noise filtering an the STEP signal A solder jumper on the SR s
85. ides a full step into smaller steps by holding the stepper motors phases in between it s physical steps For example if a stepper motor provides 200 steps per revolution then a eighth step micra step driver would deliver 1600 steps per revolution Micro stepping increases step resolution and also reduces losses due to audible distortion and resonance This results in a stronger smoother operating drive When microstepping you must multiply the number of steps per unit by the micro step resolution in the CNC control software Microstepping effectively reduces the step increment of a motor at the cost of accuracy because the electronic resolution does translate exactly to physical resolution Therefore you should not rely on microstepping to increase your accuracy but instead adjust your drive screw pitch when you need closer tolerances Installation Instructions Step 1 Choose and mark off mounting locations for the components The drivers will need to be close enough to the breakout board to connect the supplied IDC cables Step 2 Mount the Breakout Board and Drivers using 4 40 standoffs http www probotix com manuals3Axis SideStep mamual bim 3 16 2010 7 32 41 PM 129 3 Axis Bi Polar Stepper Motor Driver User Manual Step 3 Next mount the fuse and grounding blacks Step 4 Wire the power and ground wires Use a ground block as pictured to connect all of the grounds to a single location Do not connect the motors yet Step
86. ignal which disables the drivers built in synchronous rectification allows for wiring external diodes for reduced heat dissipation Wire one side of the jumper to 5V to disable synchronous rectification or install the jumper to ground to enable this internally on the driver A large ground plane exists for heat dissipation however the layout of the components of this driver board allows for the use of a standard 1 square BGA heatsink The board s large ground plane makes a heatsink unnecessary in many applications however use of a heatsink is recommended especially when driving motors at higher than 1 5 amps per phase An under voltage lockout circuit protects the A3977 from potential shoot through currents when the motor supply voltage is applied before the logic supply voltage All outputs are disabled until the logic supply voltage is above 2 7V the control logic is then able to correctly control the state of the outputs Thermal protection circuitry turns off all the power outputs if the junction temperature exceeds 165 C As with most integrated thermal shutdown circuits this is intended only to protect the A3977 from failure due to excessive junction temperature and will not necessarily protect the IC from output short circuits Normal operation is resumed when the junction temperature has decreased by about 15 C Measure the DC voltage between the Ref Pin and GND and adjust the trimmer as follows Vref 1 6 desired motor current
87. ing Station Concept 1 Air Knife and Drain Compact Higher cost Effective Solvent must be sprayed Residue drain Many different tubing connections No splash shield Brush above reservoir Many components Concept 2 X axis independent Decreased run time Concept 3 Horizontal Brush and Reservoir Concept 4 Vertical Brush and Reservoir Function 4 Supercritical CO Delivery Concept 1 El Springo Simple Easy to manufacture Minimal splash on work piece Simple Easy to manufacture Vertical brush Cost effective Easy to refill solvent reservoir Brush above reservoir Splash blown onto machine Air connection in front Difficult to clean Difficult to refill solvent reservoir No splash shield No compressed air Increased run time This design has many advantages including interference avoidance nozzle can be flipped and the mechanism can be dismounted The interference avoidance stems from the use of a spring This spring allows the nozzle to be pushed out of the way by an installed cleaning station The nozzle having the capability to be flipped is beneficial because it gives the operator flexibility in where the CO is applied Having the ability to dismount the delivery system is very convenient since it can be removed from the machine when not in use 28 This design also has a few shortfalls in the form of its relative complexity and its susceptibility to fatigue from repeated cycles The complexity of the c
88. intain its cleaning ability it needs to have the capability to be removed for cleaning The concepts are as follows 18 Concept I Air Knife and Drain Solvent Nozzle Hookup Brush Head 1 of 2 Figure 11 Concept 1 for the cleaning station is fixed to the table and utilizes an air knife brushes sprayed solvent and a drain for waste Concept 1 shown in Figure 11 consists of a catch basin a drain in the bottom of the basin two brushes inside the basin and an air knife above the basin In this design the tap would be blown off by the air knife which blows down so all debris are contained in the catch basin As the tap enters the basin it will rub against the brushes removing debris At the same time a solvent would be sprayed against the tap to aid in the removal of residue and debris All the waste from the process would then drain out of the basin through the drain located on the bottom of the basin The procedure of cleaning of the tap for this design would be 1 tap enters basin through the air knife 2 as tap gets deeper into the basin the solvent is sprayed onto it and the brushes remove debris 19 Concept 2 X axis independent Fixed to Table Y Axis E Reservoir Figure 12 Concept 2 for the cleaning station is fixed only to the Y Axis and utilizes and air nozzle a brush and a solvent reservoir Concept 2 shown in Figure 12 consists of a reservoir for a solvent a horizontal brush located
89. l ferritic AISI 405 wrought annealed low nickel based off that it is the least expensive material that still meets all the constraints A er DESIGN FOR THE ENVIRONMENT Motor Mounts The volume of aluminum used for both the X and Y axis motor mounts is 2 189 10 4 m 3 The emissions of the aluminum are compared to cast iron another material that the motor mounts could be produced with The motor mounts require 0 5977 kg of aluminum 6061 T4 or 1 6091 kg of austenitic cast iron Using SimaPro and the EcoIndicator 99 method the materials were analyzed to determine their environmental impact The closest materials in SimaPro used to model those selected are Aluminum 6060 and cast iron NiCr I 6000 5 814 85 5000 E Aluminum 4000 E Cast Iron 3 190 51 3000 mass g 2000 1 380 35 1000 Raw Air Water Waste Figure 40 Total emissions broken down into raw material water emissions and waste for Aluminum 6060 and cast iron NiCr I 70 o o aa ee es Gh eee ee 46m eta A ll a BECHER a KEE lna e ee A mr Cu x EL MEC A pi ip D l l 1 I I L 7 I 1 l l I I l l l 1 ee rm rm dln e zm rm ee zl AA ACE E EE n ee rm rm dln ee ee zl E le ze e m gee pa E ft E RENE E E eee at Minerals Aridif ication IS pU Radiation Sizer layer Ecobon city Eutrophicabo change ca BE arco 5 6060 1 MN sr 1 Comparing 0 558 kg AIMS
90. lash to the level required in our design The drawback of the ball screw is its expensive cost and the connection of the screw to the table will need to be rebuilt Table 6 Backlash Removal Comparisons Spring and Extrusion Inexpensive Not compact Introduce extra friction Holding force may not be enough Belleville Washer Inexpensive Extra friction introduced Provides holding force Compact Robust Thrust Bearing and Spring Introduces little friction Holding force may not be enough Not compact Ball Screw Provides holding force Needs resign of the internal structure of table Robust Expensive 300 each screw Little internal friction Precise 26 Table 7 Backlash Removal Pugh Chart Backlash Removal Spring amp Extrusion Ze Washer Bearing A Spring Ball Screw Cost Holding Force OA Compactness LL H polo Introduction of Friction 0 JL HL 1l SimplitytoIncopoate JL LL A Routes LL Lil Total Score II 34 23 J 2 Function 3 Cleaning Station See Table 11 p 32 for the Pugh chart comparing each design and Table 8 p 28 for an outline of the advantages and disadvantages of each concept Concept 1 Air Knife and Drain There are many advantages to this design The first advantage is that it provides very effective cleaning of the tap The air knife is much more efficient than a standard nozzle removes the necessity of have the tap spin while being blown off The programming for t
91. le was then found by multiplying the spring deflection for each of the axis by the spring constant From this Equation 2 was used to find the maximum toque by converting units 1t was found the maximum torque required to rotate the lead screws of each axis as 64 oz in or 0 45 N m The results are summarized in Table 13 T Fxr Eq 2 F the force due to the spring r the moment arm of the force Table 13 Lead screw torque analysis results Spring Constant N in 1 848 Table Position Resolution The resolution in the table positioning system was analyzed using the relationships of the step size number of microsteps and the pitch of the lead screw The pitch of the lead screw is 10 threads per inch which means that for every revolution of the lead screw the table will be moved 0 1 inches or 2 54 mm The driver that is being implemented has a micro step of 1 16 which means that there are 16 micro steps per motor step The motor has a step size of 1 8 which results in 200 steps per revolution These characteristics of the system along with dimensional analysis results in a resolution of 0 79 um were done Equation 3 summarizes the analysis of the table position resolution 1 rev 1 step 2 54mm um E E ba 200 steps 16 micro step l rev microstep Table Movement Speed The table positioning speed is a function of the motor drive speed and the position resolution The motor torque speed graph shown in Figure 24 pg 34 shows that at a torque o
92. lipped is beneficial because it gives the operator flexibility in where the CO is applied The interference avoidance comes from the use of the flexible washer A listing of the advantages and disadvantages is given in Table 9 p 29 and the Pugh chart ranking the concepts 19 shown in Table 10 p 30 Table 9 The Advantages and Disadvantages of CO Delivery Concepts Supercritical CO Advantages Disadvantages Delivery System Concept 1 El Springo Nozzle can be flipped Relatively complex Interference avoidance Fatigue from repeated cycles Can be dismounted Concept 2 Der Stange Simple No interference avoidance Nozzle can be flipped Can be dismounted Concept 3 Verwirren Nozzle can be flipped Complex Interference avoidance Many components Dismount is cumbersome 29 Table 10 CO Delivery System Pugh Chart Supercritical CO Concept 3 H AA H ALPHA DESIGN DESCRIPTION The alpha design shown in Figure 18 was formed by taking the best concept of each of the functions The functions of the alpha design are discussed in detail in the following section as well as how the design meets the engineering specifications Supercritical CO delivery Cleaning station Figure 18 Alpha Design 30 Motor Selection The alpha design utilizes stepper motors due to their various advantages over other motors They provide holding torque which allows them to lock the table in place during testing Stepper motors are als
93. m may benefit from taking the entire system out of the fume hood where it is currently and cleaning both the Microtap machine as well as all interior surfaces of the fume hood and create a schedule and procedure for maintaining cleanliness of the setup CONCLUSIONS Professor Krauss utilizes a Microtap tap torque machine in order to test the effectiveness of metalworking lubricants He does this by applying a given lubricant to a predrilled hole and then taps it recording the torque that was required to do so These measurements can then be extrapolated to other metalworking processes Occasionally test lubricants are mixed with supercritical CO and then applied to the work piece The supercritical CO acts as a coolant chip evacuator and a carrier for the other lubricant Currently the Microtap machine that is being used does not have an automatic table This means that the Operator must manually align each hole to be tested with the tap Not only is this process time consuming but it also introduces inconsistent errors in the torque measurements Because of these reasons we have been tasked with automating the table along with creating a cleaning station for the tap and a mount for supercritical CO delivery In order to generate concepts we created functions based off of the customer s requirements Once we had these functions laid out we created a morphological chart in order to explore all possible solutions to the problems We then took th
94. minimize or eliminate errors caused by human inconsistency Professor Krauss also studies the use of supercritical carbon dioxide as a lubricant both on its own and mixed with an oil based lubricant and he needs a method of reliably applying this lubricant to the hole surfaces for testing Backlash is a major concern and must be eliminated or at the very least minimized There are various approaches to eliminating backlash so a careful analysis of the methods available is necessary to choose an effective method The expected outcome is a fully automated tapping torque testing machine that can run on its own under the following conditions The user must 1 Insert the desired tap into the machine Select the appropriate hole pattern type from a list in the operating program on a PC Input the number of holes in the plate to be tapped Choose which holes to be tapped Define the hole sequence to be tapped Select the number of cycles the tap must run through the cleaning station between each test Align the tap to one or more reference points on the plate Start the tapping process EC QUE UE AE CR Se Customer Requirements The customer s requirements are summarized into nine aspects Most of the customer requirements are focused on precise hole alignment reducing the time of testing and minimizing the cost Precise hole alignment will result in better data and fewer necessary tests saving time and cost For this reason precise hole alignment is
95. nd Brush flange The tin can flange and the brush flange were made from a tin can simial to the one which served as the acetone reservoir The tin cans were cut by the band saw to obtain the desired flange shape and then the flanges were attached to the reservoir by soldering The brush flange was drilled to create two screw holes before soldering Brush A brass wire brush was cut by a band saw for a certain length to fit the cleaning system After cutting the part with brass wire was drilled and tapped to create screw holes so that it could be fastened with the brush flange Changes between final design and prototype The only change that has been made for cleaning station is that the strike plate wasn t used due to its incompatibility with the table s movement During the above manufacturing processes the corresponding engineering draws were utilized to determine the machining profile drilling and tapping sizes as well as the soldering location The cutting speeds were predetermined by the machinery s hand book and Eq 13 Pg 46 The components fabricated for cleaning station with corresponding tools information and operation conditions are summarized in Table 18 Table 18 Components fabricated for cleaning system oo O Cleanimgplatel Cleaning plate2 Cleaningplate3 Material Rie A lain AI 6061 A Waterjet cutter Waterjet cutter Waterjet cutter Op Condition Reter to Instruction Refer to Instruction Refer to Instruction Mf
96. nect yellow and orange and tape of AND Connect white and brown and tape off Tie black and orange together AND Convert to i Farallel Tie red and brown together AND Tie white and blue together Tape off black yellow red and white OR Tape off orange green brown and blue 128 Wire Gonnection Diagrams A Lead 6 Lead Unipolar Connection Yelow 30 2 Grasa 6 Al White Blue i 12 m 8 Lead Bipolar Series Connection 6 Lead Bipolar Series Connection Black 4 N C Sie 10 2 Green S Led NC Blue ej 2 1 8 Lead Bipolar Parallel Connection Red ae Jo Brown A chopper drive allows a stepper motor to maintain greater torque or force at higher speeds The chopper drive uses Pulse Width Modulation and current sense feedback to regulate a constant current output of the drive transistors The chopper gets its name from the technique of rapidly turning the output voltage on and off chopping to control motor current Low impedance motor coils will deliver the best performance for a chopper driver The chapper drivers main benefit is allowing you to overdrive your motors with a higher than rated supply voltage which will charge the coils faster 5o long as you do not exceed the breakdown voltage of the stepper motors coils and do not exceed the rated voltage of the drives you will benefit from faster acceleration and higher top end speeds without harming your motors Micrastepping electranically div
97. need to measure each axis independently To measure each axis we will be moving the table a variety of distances from 1 mm up to 45mm on the Y axis and from 1mm up to 50mm on the X axis Each axis will be tested in 1 to 5mm increments and testing the accuracy over 100 tests in order to be able to predict accuracy and repeatability for each axis The targets for the system will be 30um for accuracy and 1 3um for repeatability One other option we are pursuing is finding access to a coordinate measurement machine CMM These machines are generally extremely accurate and may produce a clearer picture of how well we meet our goals 59 Limit Switches and Emergency Stop Button The emergency stop button mounted on the wiring case was tested as soon as we had the motors running and before we attached them to the system It stops all motion of the table as soon as it is pressed as we expected The limit switches work and we have installed mechanical stops on the table as well as a safe guard If the limit switches fail for any reason the mechanical stops installed will prevent damage to any other systems as the motors will not be damaged by the attempt of the system to continue motion against the mechanical stops Full Scale Testing Full scale testing will be run in three stages The first stage of testing will be done as a dry run only moving the table automatically This will be done to verify that the table moves as expected and can actuall
98. ng drawing of the revisions needed on the table top for limit switches 105 AULA THO PLACE Dora THESE PLACE DE Baal MTS Gch ec TOURS POS E E Figure 78 Engineering drawing of the T slot nut 106 UNLESS CY HESE SPECIFIED DEEE RET H FHS ks T lt 356 2 PRAT eal X ARCILLA E MACHE BET E CE xmotormount s ud HTIE PST GC TOLIF AE HES PIS Figure 79 Engineering drawing of the X axis motor mount assembly 107 01 496 DESS Ge ART H HHE bs iasa MES A X LM ee AC et ET MAC THOS PLACE CC Rad THEEE PLACE DIECIAEL 5 A a z 1 Figure 80 Engineering drawing of the X axis motor mount plate 1 108 MESS LE HEE SFECTEO DAMEHEXCHS ART H THES TOURAN CTA AMGULAR MACHi BEHO t TWO PLACE SOMA HEET PLACE DE RASL DWG HO DO HON SCALE DRAWING SCALE 171 EKSHTI SHEET 1 OF 1 5 A a z 1 Figure 81 Engineering drawing of the X axis motor mount plate 2 109 HLESS LE HEE SFECTIEO A s R A PCH Bt THO PLACE DECORA f THEEE PLACE DE RAL x HTIE 7211 Ge EC TOLIF APA s PES CAME HO DO HON SCALE DEAN SHEET 1 OF 1 1 Figure 82 Engineering drawing of the X axis motor mount plate 3 110 ANGUL TWOFACE DECAL THEEE PLACE OBCFAEL 4 5 A a Z 1 Figure 83 Engineering drawing of the modified X axis lead screw 111 2x 06 201 2 000 5 750 4 250 2 109 1 661 1 181 I 4X 150 c 4 X QD 257 DAPET ART IN CHES TOLERAMCE
99. o a cheaper alternative to both servo and linear motors Steppers can also be operated with no feedback control The motors are connected directly to the lead screws using shaft couplings to prevent backlash between the motor and lead screw shafts Stepper motors basic step sized 1s 1 8 degrees however they can be micro stepped Cleaning Station The alpha design of the cleaning station subsystem makes use of the best features of each of the concepts Figure 19 p 31 shows the final design and how the individual pieces fit together Solvent Bath Cover Brush not visible inside solvent bath Solvent Bath Mounting Bracket Figure 19 Alpha Design Cleaning Station The basic design is built on solvent bath An air knife is used to remove metal shavings from the tap before it enters the solvent bath The shavings are blown into the bath to prevent them from getting on the test bar The solvent bath is covered to prevent solvent from splashing unto the test bar during cleaning The bath is connected to a bracket by flanges on the back so that it can easily be removed and cleaned during testing The bracket is fastened to the top of the table using T nuts places in the T slot A brush is submerged in the solvent bath to help clean the lubricant off the tap By keeping the brush submerged it prevents lubricant that 1s in the brush back on the tap negating the entire cleaning process Because the alpha
100. olar chopper drivers are by far the most widely used drivers for industrial applications Although they are typically more expensive to design they offer more performance and increased efficiency Bipolar chopper drivers use an extra set of switching transistors to eliminate the need for two power sources Additionally these drivers use a four transistor bridge with recirculating diodes and a sense resistor that maintains a feedback voltage proportional to the motor current Motor windings using a bipolar chopper driver are energized to the full supply level by turning on one set top and bottom of the switching transistors The sense resistor monitors the linear rise in current until the required level is reached At this point the top switch opens and the current in the motor coil is maintained via the bottom switch and the diode Current decay loss over time occurs until a preset position is reached and the process starts over This chopping effect of the supply iz what maintains the correct current voltage to the motor at all times e Hardware or software selectable phase enable and direction signals Current limit adjustable by potentiometer Wide range of motor power 5 35 V Power for logic indicator LED x2 5 A 35 V Output Rating htgp www probotix com manuals 3Axis SideStep manual htm 5 16 2010 7 32 41 PM 125 3 Axis Bi Polar Stepper Motor Driver User Manual Automatic Current Decay Mode Detection Selection Mixed
101. oncept will slightly increase its cost and increase the manufacturing time The repeated cycles that the mechanism will undergo may cause it to fail eventually so it must be designed to ensure that it does not fail in a short period of time Concept 2 Der Stange There are many advantages to this design which include its simplicity ability to be flipped and that it can be dismounted Because of its simplicity this concept would be cost effective and very easy to manufacture With the ability to be flipped this design would allow for the CO to be delivered from either the top or the bottom of the work piece The ability to be dismounted when not in use makes this design very convenient This design however has no interference avoidance and it therefore would not be selected for the final concept unless it was modified to include that feature Concept 3 Verwirren The disadvantages of this design include its complexity the amount of parts and the dismounting is cumbersome The complexity is due to the addition of interference avoidance and this increases the number of parts needed The manufacturing time would be slightly increased as well as the cost Because of the robust attachments and the fact that there are two of them the dismounting 1s relatively complicated The advantages of this design are that the nozzle can be flipped and the flexible washer gives the attribute of interference avoidance The nozzle having the capability to be f
102. op of the reservoir in order to minimize evaporation of the acetone and also contain any splashing while the tap is being cleaned Another flange 2 was attached to the outside of the tin can by soldering This flange would allow the reservoir to be easily removed from the cleaning station mount 52 Cleaning station mount 1 Sopportbiocke TT 2 eteaninaptater TTT Cdeonngnotez 17 IEC E ME 4 acens trey 1 7 sw 12 raras 13 UNLESS OTHERWISE SPECIFIED DIMENSIONS ARE IN INCHES TOLERANCES n FRACTIO NAL 2 TITLE ANGULAR MACH BEND 3 TWO PLACE DECIMAL THREE PLACE DECIMAL cleaningstationexploded INTERPRET GEOMETRIC TOLERANC ING PER SEH SEE DWG NO REV FINE H A DO NOT SCALE DRAWING SCALE 1 4 WEIGHT SHEET 5 A 3 2 1 Figure 35 Assembly drawing of the cleaning station Description The cleaning station mount was attached to the table through the support block 1 A cleaning plate 1 2 was screwed into the side of the support block by two screws 7 Another plate 3 was attached to plate 1 2 by TIG welding The cleaning plate 4 which cannot be seen in the above picture was also welded to cleaning plates 1 and 2 to add rigidity A back bracket 5 was screwed into plate 2 by three screws 8 This back bracket provided a means for the acetone reservoir 6 to be easily mounted and removed from the assembly Changes between final design and prototype The strike plate was taken
103. ough the enclosure and this seems to be working properly right now but after running a full test it is possible that the temperature of the drivers or power supplies can reach temperatures that will damage them Through our current testing we watched the temperature of the drivers simply by feeling them to see if they were overheating and they still felt cool after an hour of testing It may be useful to use a thermocouple to measure the temperature of the drivers through three 3 hours of testing to make sure they do not over heat Mechanical System First issue that arose during testing was that the thrust bearing between the X axis handle and the support bracket would bind causing the motor to stall It was determined that this was caused when the key used to hold the handle in place would stick out into the thrust bearing where it would eventually prevent a ball in the bearing from rotating and bind the entire axis This was remedied by placing a flat washer between the handle and the thrust bearing This prevents the key from interfering with any of the balls in the thrust bearing Second issue was that when turning the lead screws the lathe was not center and so the end of the shaft that connected to the motor was off center and this caused the table to wobble This was fixed by milling off the end and drilling an undersized hole into the end of the lead screw A steel dowel was then pressed into the hole with Loctite to prevent the dowel from rota
104. pou g epon das ma TU P EL E Ki Saa SN abr gr zz h s o aro PU ME B sdwe juam een 438A jee OOOO isa Ee mo ETOTE DE LIT IIT E IT TI TH a a a En d EIER d o po opp m d3150Q01d Stepper motor driver datasheet 136 Seu HIE 3e Jo3ouu oU oj ebeyoA 3usun Pao etg SUIEQUIEW 3euw s Ajddns eu yo Dog Gurddoyp siu Jano speg sseDoud ayy pue paypea si uonisod saud e gun sAexep auno etg pue suedo us etg quiod SILA Jy petes si hel paunbea eu qua JUEUND Ul asu Jesu etu SUOPUOW 10751581 esuas eu sJojsisuen Durs eu yes euo uo Duruy Aq jana Apddns nj eu 01 pezibueue sue leAup Jaddorp e Dun sbuipuiM IOON seuils Jojsisuer apis Mo eu o Det si 100 484 ypes jo pua ugo ayy pue jro geu yes Jo apts auo og no ds Si Addins eu jo epis ubi au queno OO et o3 euoniodoud abeyoA xoeqpasl e SUIPJUIELU JEL JOIE esuas e pue sapoip Bugene sapnu MOD eu r How Jaddajs e Jo sesetd J eu mog eu JO yes aj WALNI eu ojuo2 SISAUp YUS JNO Jo yes Y O QUOD JOJO ae jo uuo 1sepduiis ei aie susup SE i d ell D vops304d yn usdo pue poys pajusjeg sjndjno aet yo 359 eu paguo Appanoo o qe usu Si 3ibo Jouguco BU AC a oge si abeyoA Ajddns ibo eun un perqesip sue sjndjno Ivy abeyoA Ajddns 2160 eu aia padde si abeyjon Addins 103041 eu usu s3uaun ubnap oous Jenusjyod way 6 V eu seyd NID yopo ebeyoa repun uy sdue T uetp Jajeaub ye sogo DurAup usu pesn eq ISNW qulsjesy e os uonxsgoud PUL an
105. r shaft The welding was conducted using the TIG welding technique Before welding the welded part must be cleaned by using acetone and a rag Then a metal wire brush was used to remove the oxides layer on the surface of the welded part to prevent contamination Changes between final design and prototype In order to prevent accidental damage caused by moving the table too far we designed and manufactured four mechanical stops which were attached the table base Correspondingly four electrical triggers were attached at the table base Once the mechanical stop hits the trigger the trigger will send electrical signals to the computer and the system will be stopped immediately Another change is a new Y handle was made since the original y handle could not be mounted to the shaft of the Y motor During the above process the corresponding engineering drawings were referenced to determine the cutting profile the size of the drill bits and the taps and the location of the holes The speeds for cutting and drilling were predetermined by the machinery s hand book and Eq 13 Pg 46 The components fabricated for the power system corresponding tools information and operation conditions are listed in Table 17 Table 17 Components fabricated for power system Lo X plates Xplte1 X plate Op Condition Mfg Process TIG welding TIG welding TIG welding rod of 5356 AI rod of 5356 Al rod of 5356 Al 48 Process ToolInfo Ria Q25
106. re L Aluminum 6061 wrought T4 2 Aluminum 6061 wrought T451 3 Aluminum A356 0 c LM25 TB7 cast 4 Aluminum 6061 wrought T42 J Aluminum S319 2 a LM4 M cast Out of these Aluminum 6061 T4 is the best material to use for the motor mounts due to its strength durability and having the lowest price of 1 57 1 73 USD kg Acetone dish The function of the acetone dish 1s to hold a capacity of acetone that will be used to clean oil off a tap A brush will also be installed on the inside to assist with cleaning The objective is to find a material that can be stamped and fastened without screws The material must also be resistant to any corrosion that comes from holding acetone or other solvents Using CES EduPack 2009 the following constraints were applied Price less than 5 USD kg Non flammable Excellent durability to weak acids Excellent durability to Strong acids Excellent durability to organic solvents Excellent durability to oxidation at 500 Deg C Recyclable Based on these constraints the top five results ranked for price from lowest to highest are 69 Stainless steel ferritic AISI 405 wrought annealed low nickel Stainless steel ferritic AISI 409 wrought annealed Stainless steel ferritic AISI 429 wrought annealed Stainless steel martensitic AISI 410S wrought annealed Stainless steel martensitic AISI 410 wrought intermediate temper Form this list the selected material is Stainless stee
107. resolution but as a general rule accuracy is greater than or equal to repeatability and three standard deviations of repeatability is greater than or equal to resolution Neither the Microtap Autotable nor the CNC Jr Mill have a cleaning station and we have not been able to find a solution to fit our needs available on the current market so we will have to design and build a 12 completely new system We have also been unable to find a standard delivery system for the supercritical CO necessitating a custom solution for lubricant delivery as well Figure 1 Microtap Autotable Figure 2 CNC Jr Mill CONCEPT GENERATION According to our customer requirements the main functions of the automated table have been identified as follows 1 automate table movement 2 clean tap 3 deliver supercritical CO2 4 remove backlash 5 align holes accurately 6 drive the table 7 user interface flexibility A morphological method is employed along with literature research to develop various concepts for each function as shown Table 3 p 13 14 Table 3 Morphological Chart Stepper motor PP Electromagnets Automate the Table Movement S amp Align Holes Accurately near motor Programs d Open loop or closed Transmission loop control Spring amp extrusion Belleville washer Thrust bearing amp spring Constant pressure Remove Backlash chamber Closed loop control 13 ni ol RA zm solvent Open
108. resolution we will use an appropriate controller to incorporate with the stepper motor for micro stepping The justification of micro stepping will be given in Appendix C Another drawback is that since a feedback mechanism is not used the precision will be limited by how well the backlash is removed Servo Motor The precision of a servo motor can be theoretically infinite but in reality the precision will depend primarily on the resolution of the feedback device used in the closed loop control system The closed loop control will contribute to reducing the backlash but on the other hand the additional sensors controller and more complicated program used in the closed loop control will increase the entire cost and labor For instance a typical controller that meets our standard would cost more than 300 dollars Other drawbacks are that the servo motor does not provide any holding torque and the 400 dollar cost is relatively high The manual control of the table will be feasible after the installation of servo motor Linear Motor The main advantage of the linear motor 1s that it provides the linear force directly and the resolution and precision is good enough to meet our engineering specifications However the linear motor needs to incorporate with a feedback mechanism it does not provide holding torque and doesn t support manual control a new connection for the motor and the table will be needed to mount the motor Last but not least the
109. rication plan for the design The operation conditions of machining have been carefully justified using the machinery s handbook as well as 64 consulting with relevant instructors We have also put together a validation plan to determine and test how well the requirements will be met in the finished product ACKNOWLEDGEMENTS We would like to thank the following people who for their help and support during the course of this project John Baker Phillip Bonkoski Bob Coury and Marv Cressey Steve Erskine Professor Gordon Krauss Professor Katsuo Kurabayashi Sarang Supekar INFORMATION SOURCES To obtain an idea of how well our product should perform we researched similar products that are currently on the market We researched a few CNC machines with automatic tables 3 6 and as benchmarks analyzed an automatic table from Microtap 2 and the automatic table of a countertop CNC machine 3 Neither the Microtap nor the CNC machine have ways for cleaning the tools or have a mount for supercritical CO The Microtap also has a very hefty price tag We then analyzed the current setup of our tap machine and compared it to the other two products For full benchmarking see the QFD in Appendix A To understand how supercritical CO could be used to lubricate and therefore design an appropriate mount for it the patent on the delivery system was researched 1 From this patent we learned that the supercritical CO exists at 31 1 C and 72 8 atm
110. s designed to reduce the backlash in the Y axis The entire table base was attached to the slide base which was not shown in the drawing by the Y screw nut 57 Cost Analysis for Mass Manufacturing The section discusses the cost that would be involved for mass manufacturing of the product and provides an estimation of the cost As justified the section of manufacturing process selection the production volume for our prototype is estimated to be around 100 units due to it is for research use The majority of the components will be produced using CNC machine with 6061 aluminum where the CNC machine will be taken into account as capital cost The solvent reservoirs would be most cost effective if they are purchased from an outside party rather than manufacturing them The rest components such as motors drivers encoder as well as the fasten components will all be purchased from outside party to reduce the cost Since the production volume is low we assume mass manufacturing won t reduce the cost in raw material Due to the low production volume it is recommended to use labor to assembly and test the prototype rather than employ automatic manufacturing line to do that The estimated time for manufacturing assembly and testing will be 10 15 hours Table 19 summarizes the estimated cost for the above mass manufacturing plan Table 19 Estimated cost for mass manufacturing of automated torque tapping test system t Cost per Cost per unit
111. s of the cleaning station is effectively a qualitative measure we will be conducting further testing to ensure that the cleaning meets the standards Professor Krauss needs 11 BENCHMARKING To understand how well our product should perform we researched similar products that are currently on the market We researched a few CNC machines with automatic tables 3 6 and analyzed an automatic table from Microtap 2 and the automatic table of a countertop CNC machine 3 to use as benchmarks for our system Neither the Microtap nor the CNC machine have methods for cleaning the tools or have a mount for supercritical CO The Microtap also has a very hefty price tag 9750 00 We then analyzed our current setup and compared it to the other two products For full benchmarking see the QFD in Appendix A Currently the use of a stepper motor is thought to be the best way to move the table in both the x and y directions for high torque loads at low to medium speeds lt 3000 RPM The decision is based on the fact that stepper motors can approach the accuracy of conventional DC motors and also can provide a holding torque which acts as a lock when the motor 19 powered but not moving This would prevent the table from moving when external force is applied to it The advantages and disadvantages of stepper and servo motors are discussed in the concept generation section of this document Benchmarked Products Several products were researched for the ben
112. t aluminum 6061 T4 for the motor mounts and stainless steel AISI 405 for the acetone dish With the aid of both the CES EduPack 2009 and SimaPro software we selected the materials and also analyzed their safety and environmental effects Simapro did not have aluminum 6061 so we measured the environmental impact of aluminum 6060 instead which was the closest material to 6061 T4 We found that 5977 kg of aluminum would be needed for the motor mounts as oppsed to 1 6091 kg of steel Aluminum has a low raw material impact on the environment but cast iron has lower air and water emissions The cast iron also produces less waste Our results however show that over the course of the components lifetime aluminum actually has a lower environmental impact Refer to Appendix C for the full material analysis When analyzing the conditions of manufacturing our project we estimate that around 100 units would be made After selecting the materials to be used for the motor mounts and the acetone dish we determined what the best ways for producing 100 units of each would be The motor mounts made of aluminum 6061 T4 would be machined by a CNC mill The capital costs for this process would be relatively low which is a major consideration since so few parts are being made The acetone dish though would be created by sand casting Similar to CNC milling the capital costs are low and the sand casting process 1s ideal for low production volume It would probabl
113. the back of the machine since there 1s no splash shield The station would also be difficult to refill and clean because there is no way to disassemble it and it is located on the back of the table Concept 4 Vertical Brush and Reservoir There are many advantages to this design To begin with it is very simple There are only three components and only two of them would need to be fabricated by us Because the components are so simple this design would be very easy to manufacture This simplicity makes 1t very cost effective The vertical brush is also a positive because it can clean the entire tap length at once and the brush bristles would align with the threads in the tap Because the station could be mounted to the front of the table this design would provide convenient refilling of the solvent reservoir There are however many shortcomings of this design First there is no splash shield When the tap spins against the brush any debris or residue on it will be propelled all over the work piece and work area Secondly there is no compressed air Not only would this affect the overall cleaning ability of the station but the tap would resume testing covered in solvent which can affect the test results Lastly the run time of the process would be increased as a result of the increased travel distance required which arises from the placement of the station being at the end of the table Table 8 Advantages and Disadvantages of Each Clean
114. the most important customer need and the rankings of other requirements are based on the correlation to precise hole alignment ePrecise hole alignment Professor Krauss requires the tap to be aligned with the test hole precisely to minimize any effect misalignment may have on the data collected eAutomated table control Professor Krauss wants the table to be fully automated so that it can line up the tap correctly and run the experiment more efficiently 10 Automated tap cleaning ability The new system is required to be able to remove chips as well as lubricant residue from the tap so that multiple lubricants can be tested in one cycle with minimal user interaction eSupercritical carbon dioxide lubricant delivery Professor Krauss also wants the supercritical CO lubricant delivery system configured to spray the lubricant from the underside of the work piece The option of adjusting nozzle to spray from above the work piece 1s desirable but not a requirement eLow cost The new system should cost less than current systems that exist in the market and meet the requirements Typically the customer wants the budget to be 400 dollars eSimple flexible computer interface Since testing involves different hole patterns materials tap sizes and user defined hole sequences a simple flexible computer interface will be extremely helpful to the users eManual control capability Manual control of the system must be preserved Minimum
115. the table thus minimizing backlash 45 FABRICATION PLAN The purpose of this section 1s to provide manufacturing and assembly processes involved in the production of the prototype as detailed as possible so that the readers can understand the implementation of the design and be able to reproduce it The fabrication plan also notes the changes between the final design and the prototype and it discusses the corresponding updates of the fabrication plan Last a tentative cost analysis for mass manufacturing of the prototype is provided The fabrication plan is classified into four major categories including the engineering drawings manufacturing plan assembly plan and cost analysis for mass manufacturing Engineering Drawings This section provides the engineering drawing for each the components that will be fabricated These drawings are supposed to be used in the corresponding manufacturing process All the drawings are made using SolidWorks 2009 SP3 0 and are provided in the Appendix G Manufacturing Plan This section discusses the manufacturing plan regarding all the components fabricated The details of the manufacturing processes tools used and the operation condition are provided with careful selection The manufacturing plan is categorized by the different function that each system serves These systems include supercritical CO2 delivery power system and Cleaning Station Supercritical CO delivery Aluminum components A waterj
116. ting Third issue was that during manufacturing a tap broke during tapping on a hole that was used to hold the cleaning station to the support block To fix this new hole were drilled 3 8 to the side of the original holes We were able to do this because the position of the clean station along that axis was not as important as any of the other axes DESIGN CRITIQUE Our design as built has some issues that can be addressed Some of these issues can be fixed before submission of our final prototype while others will be noted here as future work to be completed as we may not have resources to address them before our due date Any changes we make to the system will be included in engineering change notices ECN s to accompany the final prototype 1 Backlash As of this report both axes still have a slight problem with backlash as reflected in our accuracy errors earlier PXX LXX Our use of thrust bearings along with Belleville washers was fairly effective for the X axis though there is room for minimal improvement The Y axis will require an entirely different approach as the screw 19 mounted to the table base rather than the moving axis To fix the Y axis we will need to modify the nut it is running through though we believe this can be accomplished without affecting the total travel of the axis 62 10 11 The blocks we machined to hold the test bar high enough for the CO delivery system to be functional are off slightly
117. tity AIP IKA lA lA NIN JP IA lG Im lA IN lA lA lA IK 1 lA lA IK lA IKA IRIN lN IN lM lA IKA IR lA KA N Price ea 299 95 149 00 S S S U DY UN UN UN UN UN UN UN UN un UY UN UN It U UU UN UN UN UU UN UN UN U U UN U 24 95 1 75 7 98 33 30 20 99 6 99 2 64 2 59 2 59 1 99 1 99 3 49 3 49 5 97 3 21 4 62 9 35 0 66 25 66 16 67 16 38 4 34 20 07 46 89 0 13 0 12 0 01 0 18 0 12 0 11 0 51 0 10 0 10 Part N A N A N A N A N A 35A AAA DDBA 1BA N A N A N A N A N A N A N A N A N A 94135k23 6655K350 9712K438 99129A325 3201128 8975K565 8975K371 9246K11 7451119 61005K311 33345K9 912514540 91251A196 912514242 91253A540 91251A537 912514245 912514711 912514242 912514081 Notes 2 axis Monster CNC Stepper motor driver kit Mach3 45000Hz 6axis controller E Stop switch Limit switches Cooling fan Solenoid valve 12 VDC power supply 1 54 12 VDC auto relay 5 VDC relay 6 pin female connector 6 pin male connector 2 pin female connector 2 pin male connector Fuse block Solder Extension spring pack of 3 3 8 thrust bearing 1 2 Belleville washer pack 12 Hex nut pack 5 U bolt Aluminum 2 x4 x6 Aluminum 3 8 x8 x12 Aluminum 1 4 x6 x8 Brass wire brush 1 4 shaft coupler Flexible blowoff nozzles mag base SHCS 1 4 20 x 3 4 pack 100 SHCS 8 32 x 5 8 pack 100 SHCS 10 24 x 1 2 pack 100 FHSCS 1 4 20 x 3 4 pack 50 SHCS 1
118. tor mount 54 5 E 3 PEE MER NN DIMENSIONS ARE IN NCHES ANCES A LAR EI ureien xmotormount IOLERKANCINC PEF SIZE DWG NO S BENI SCALE 1 2 WEIGHT SHEET OF FINISH DO NOT SCALE DRAWING 2 Figure 37 Assembly drawing of the X axis motor mount Description The x axis motor mount consists of 4 components The motor itself was attached to the large plate through the use of screws Another plate was needed attach the mount to the table This was done by taking advantage of the T nuts that are on the table To attach these two plates two L plates were welded onto the joint to add strength and rigidity 55 X Axis ITEM NO PART NUMBER DESCRIPTION O 7 y UNLESS OTHERWBE SPECIFIED 5 latl rcge icis TOLERANCES ez CC TTE 5 xelete3 ANGULAR MACH 2 BEND 2 TWO PLACE DECIMAL E 6655Ka5 Ee XOXIS LS XScrewt flange 9 Made 10 SdeBws sms IHTERPRET GEO METRIC TOLERANCING PER MATERIAL SEE DWG NO REV FIN BH DO NOTSCALE DRAWING SCALE 1 12 WEIGHT SHEER TOF 1 5 4 3 2 Figure 38 Assembly drawing of the x axis lead screw Description The motor 1 was attached to the lead screw 3 through the coupler 2 In order to support the motor a motor mount 4 5 6 was created and attached to the table This motor mount consists of three components The X plate 2 5 was what the motor itself is attached to
119. tware controlling the tap This communication is to avoid table movement while the tapping torque tester is acquiring data Movement during data acquisition would allow for tap breakage and would be risking breaking the sensors within the machine which would be an extremely costly mistake An emergency stop button must be included and will stop all movement of the table and associated hardware as a final failsafe The requirements listed above are the minimum goals that must be achieved Below are the functions we would like to provide 1f time allows In test statistical analysis of collected data This will help in characterizing tap wear and lubricant effectiveness Including a color coding system to identify lubricant types and locations as well as indicate tapped vs untapped holes Capability to read DXF files to allow for any type of hole configuration The user would still need to manually identify the limit holes and cleaning station during testing setup but it would decrease the setup time since a DXF of the plates can be obtained from MicroTap or can be drawn quickly by the user These extra goals will not be achievable in this round of testing though the end users or following student groups may be able to include them in a new program These are the specifications by which the program is being written Full test procedures and program documentation will be included in the final prototype submittal on April 27 CHALLENGES
120. ull speed If the motor does skip steps when stopping from full speed we will need to adjust the programming so that the motor decelerates slowly to avoid missing steps Before final assembly we can also test the cleaning station Once the cleaning station has been assembled we can attach 1t to the table and run trial tests to verify effectiveness of the cleaning station This will be evaluated qualitatively by Professor Krauss and Sarang Supekar The graduate student who will be running tests using our system Table Alignment As soon as the motor mounts are made and the table base has been modified to fit the motors we can attach the motors and limit switches to the table and begin testing the accuracy and repeatability of the system The first thing to do is to make sure that the table is mounted onto the base of the Micro Tap machine with the axes lined up correctly While the programming should be able to compensate for any misalignment it shouldn t have to if we align everything correctly during final assembly We will be using an optical laser measurement system borrowed from Professor Brei s research group Once the table is attached to the MicroTap base we will need to mark clearly on the base of the machine where the edges of the table base need to be for correct alignment in case the table needs to be removed again Testing Accuracy and Repeatability To test the accuracy of the system we will be using optical measurements We will
121. ver many drawbacks to this design The biggest fault is that the brush is located above the reservoir which means that the tap would be brushed off before entering solvent This is a problem because the tap would travel through the brush again on its way out of the solvent and any debris or residue on the brush would be retransmitted to the tap The design also does not consist of any sort of splash shield so that any debris or residue blown off by the compressed air would be blown all over the work piece Another issue 1s that the design is not very simple There are many slides and components involved and all of these must be machined and fabricated Concept 3 Horizontal Brush and Reservoir The advantage of this design is that it 1s relatively simple It requires no specially fabricated parts or methods and would be easy to manufacture It would also blow debris away from the work piece This design also has many disadvantages The biggest fault 1s that the brush is located above the reservoir which means that the tap would be brushed off before entering solvent This is a problem because the tap would travel through the brush again on its way out of the solvent and any debris or residue on the brush would be retransmitted to the tap Secondly because the compressed air is mounted to the front panel of 27 the machine the hose connected to the nozzle may get in the way of the operator and be a nuisance In addition the splash would cover
122. y be however more cost effective to purchase a dish from an outside vendor as was done for this prototype Refer to Appendix C for the full analysis 38 FINAL DESIGN DESCRIPTION The final design shown in Figure 26 pg 37 was formed by refining the alpha design and addressing the shortcomings The functions of the final design are discussed in detail in the following section as well as how the design meets the engineering specifications Refer to Appendix G for engineering drawings of fabricated components and Appendix F for a bill of materials Supercritical CO Delivery Cleaning Station Height Blocks The height blocks raise the work piece 3 inches and also moves it forward about a half inch This change was instituted because after further consideration we decided that it wasn t ideal for the supercritical CO to pass through multiple valves and pipes with different diameters however minute those changes may be We decided to create an assembly that simply mounts the hose and nozzle that originates from the CO pressure chamber To enact this change we needed more space under the work piece While were modifying this aspect we decided it would help to also move the work piece forward to allow more room for the cleaning station also Cleaning Station Changes from Alpha design A few changes have been instituted related to the cleaning station We had to mount it higher because the work piece is now higher so instea
123. y compensate for rotation of the bar or table away from square An entire bar will be tested without the Microtap machine powered we will manually manipulate the programs running the system and manually actuate the tap during this verification Once this test is completed if we need to make any adjustments we will do so and test again When we are satisfied with the results of this test we will move on to stage two of full scale testing The second stage of testing will be done using a previously tapped work piece and a used tap in case any errors do occur during validation We will start by running a test on one column of holes to understand the timing and verify again that all of our controls are working as they should be Once we are comfortable with how the testing is running on a small scale we will run at least one full scale test at least 100 holes still using a previously tapped work piece At this point if there are any changes to be made to the system we will make them and time allowing move on to stage three of full scale validation testing Stage three of full scale testing will be on a full bar with a new tap including all data collection Ideally this test will be run by Sarang Supekar the final user of our system while we observe and answer any questions he may have during setup and operation With or without stage three testing we will be submitting our final prototype design on April 27 along with an update including any

Automated Indexing and Tool Cleaning for Tapping

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