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DYNACAM 10 USER MANUAL - Norton Associates Engineering

1. Model type T Show Fills I show Legend Mass properties spring constants and damping Preload Io Polydyne calculation Runge Kutta solver parameters pee or Differential Equation Solver Control 462 S xX deg Frequency 049 Hz Periods Nat Period 1 1 0m6 sec p Postion Error S 005 deg 005 deg 040 deg Motion 0075 sec TT Make Polydyne Cam Gamma p Velocity X dot Start Time End Time s Cam Period 0300 sec Max Steps Accuracy Model Run Data Minimum Detta t FIGURE 15 Robert L Norton Design No 2 385 000 sec 150 95 deals 12753 deys p 27848 degs Steps Taken 12 20 2009 X dbl dot deg s 2 7 509 28 de at 17 14 41 File Model Vibration screen in program Dynacam FREAD degs p 148802 segs M Show Horizontal Grid I Show Vertical Grid s 2 Follower error s x Follower displacement x Follower velocity x Follower acceleration x ROBERT L NORTON dialog box with some instructional information Proceeding causes the follower dynamics to be recomputed as a polydyne or splinedyne function The dynamic plots are updated and should show marked improvement in their dynamic behavior Clicking the Next button at this point brings up the Profile screen in order to recalcu late the cam contour coordinates with the polydyne or splinedyne
2. Minimum Force ET Calculated Data Undamped Natural Freq Force kin Torque m rad s Damped Natural Freq radis Critical Damping Cc bs in Maximum Force lb b Maximum Torque r Ibin Average Torque Ibin Flywheel Data Coeff of Fluctuation Calculated values 0 lt value lt 1 to generate flywheel torque curve From a piecewise integration of the torque curve at left E o 8 For friction Friction Coetticients Journal Friction torque EE calculation Follower Friction oor FIGURE 13 Dynamics screen in program DYNACAM A fifth model for the case of a form closed follower train is also provided but is directly invoked without passing through this screen when form closure has been selected on the Dynamics screen Each model diagram has an Help button that will display a message describing its purpose and application Either selecting the model s radio button and hitting Next or double clicking on the image of the desired model will take you to the next screen Figure 15 shows the Vibration screen for the 1 DOF model of an industrial cam follower system Text boxes are provided for the input of the relevant effective mass and effective spring data along with assumed levels of damping The box at lower left provides control over the parameters for the 4th order adaptive step Runge Kutta ODE solver It is suggested that these be left at their defau
3. forces FIGURE 16 DYNACAM 10 USER MANUAL EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 5 12 20 09 Stress Calculation Screen Help Calculate Replot Copy Print lt Back Next gt Set All Dec Places fi Cam Material Parameters Steel C Other Young s Modulus Poisson s ratio Follower Material Parameters Steel Other Young s Modulus Poisson s ratio Follower Configuration You have chosen a Please specify type Cylindrical C Crowned Contact Lenath Crown Radius External Forces on Cam Follower weight force on cam ab Include applied external force Robert L Norton Design No 2 12 20 2009 at 17 14 41 File Model xX y coordinates Surface Stress in Cam and Follower Rho Force Dyn Sig_max Tau_max Plot Options I Show Horizontal Grid I Show Vertical Grid T Show Fills Force Dyn Ib Sig_max psi Tau_max psi Stress analysis screen in program DYNACAM Select segment Select function Select harmonics Spectral power hidden Sum of harmonics FIGURE 17 EEI DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 5 12 20 09 fan Fourier Transform Screen Help Replot Clear lt Back Next gt x y coordinates Fourier Transform of Accel E RealFFT imagFFT M MagFFT Ang FFT Function for FFT Choose a Variable Accel x Number of Harmonics
4. Refresh pisptacement Force Velocity Torque Print To DiskFile Print Hard Cop Choose Al Segments Displemnt number of a Cel ea Bl functions to Gara vad Pana print here Start angle TG End Angle J 380 Delta Angle Follower Model reat parameters are listed here i Ba Min Rho Preload Cine Type EES FIGURE 11 The Print Screen Robert L Norton Design No 2 42 20 2009 at 18 51 13 File Mode Choose print destination here Select individual items from these dropdowns zors Select any set of items in this collection Switch conjugate DYNACAM 10 USER MANUAL Creating the Cam Profile Once the S V A J functions have been defined to your satisfaction it remains to size the cam and determine its pressure angles and radii of curvature This is done from the Profile screen shown in Figure 12 which is accessible from the button of the same name on the Home screen The Profile screen allows the cam rotation direction and follower type flat or roller to be set The cam type radial barrel or linear and follower motion translat ing or oscillating can also be selected The cam start angle cam zero as chosen on the S VAJ screen is shown and a drop down box allows the keyway location versus machine zero to be selected among four cardinal positions The prime circle radius base circle for a flat followe
5. Figure 22 shows the input screen for a sixbar slider linkage The Linkage Modes define the kinematic circuits of each stage of the linkage which can independently be either open or crossed For a definition of these terms see reference 2 The Angle from Line of Link 2 to Roller Arm parameter defines the included angle between the kinematic link 2 and the arm radius to the roller Link lengths are defined as the pin to pin distances of each link Link 1 is the ground link link 2 the link directly driven by the cam and pivoted to ground link 3 a floating coupler link 4 a rocker pivoted to ground at O4 that connects Choose circuit for links 1 2 3 4 Choose circuit for links 1 4a 5 6 HE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 I akage Screen xj F on Help Calculate Redraw Zoom Out Normal Zoom In Step Run Mass Prop Copy Print lt Back Next gt Select Linkage Type Stage 1 Mode Stage 2 Mode Apply SVAJ to Cam Angle Fourkar Sixbar Fourside C Sixslide G Open Crossed open C crossed camArm EndEftector GR es Current angle Please provide the relevant parameter values for your linkage Length of Length of Link 3 Length of Link 4 Fixed Pivot 04 Fixed Pivot O4y Length of Link 5 Length of Link 6 Distance O4 to 145 in Link 4 Angle to 145 within Link 4 Fixed Pivot 06x M Animation Contr Smee Rae fx
6. Save As Plot Print Units and Quit functions REFERENCES 1 Norton R L Cam Design and Manufacturing Handbook 2ed Industrial Press New York 2008 2 Norton R L Design of Machinery 4ed McGraw Hill New York 2008 DYNACAM 10 USER MANUAL Import Data Screen EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 P g Show Derivatives lt Back Save Functions and Exit Help Import Data Fit Functions Show Data Normalization Coordinates Follower Type Interpolation Method Save Displacement Data as Polar R T Cartesian XY lle Translating Oscillating le Lanzcos C S Cubic Spline Fourier Series e Interpolated C Raw Data r Remove DC Component x y coordinates 341 025 1 017 Interpolated Velocity Function 10 os 06 04 Calculated f o velocity of an E interpolated 2 function Interpolated Acceleration Function F Show Lines I Show Data Points Calculated T Show Fit TT Show Horizontal Grid acceleration T Show Vertical Grid of an interpolated Robert L Norton function Sane 12 24 2009 at 18 09 51 File Model FIGURE 25 ed Velocity and acceleration of an imported and interpolated function ROBERT L NORTON A About Menu 8 Accumulate 22 angle toroller 28 B Spline 11 plotting 15 barrel cam radii of curvature 20 base circle 20 Beta 11 C Calculate button 20 cam vs machine zero 21 c
7. 1 12 24 2009 at 11 35 08 File Model FIGURE 4 Result of calculation of the polynomial function AE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 B Spline Screen x Help Calculate Replot Show Splines lt Back Next gt Even knots T Even Knots F Autocale On Autocalc Displem o om Interior Knots Kno t e e f locations M Bound Conditions 450 Ea Cam Angle Deg 2 sa Slt a order 450 675 Cam Angle Deg Total Knots ii m Interior Knots 450 e Cam Angle Deg 0 0231 Jerk E 3 oO Design No 2 mmiss Robert L Norton 12 24 2009 at 17 56 18 00231 File Modell FIGURE 5 Spline function screen with adjustable interior knot locations ROBERT L NORTON you to choose a spline order between four and the number of boundary conditions previ ously selected It then displays the total number of spline knots used and the number of those available for distribution as interior knots It also calculates the spline functions and displays their S V A J functions for the default assumption of evenly spaced interior knots The current locations of the knots in degrees are displayed in the right side bar The shape of the spline can be manipulated as described in Chapter 5 of ref 1 by moving the interior knots around There are several ways to do this One is to select a knot with its radio button in the right side bar
8. Next gt Cam Data 7 Global Theta Segment Local Thet Start here Number pea Boundary if it j ar TFE Condition p ba Conditions boundary Requested conditions for TT Boundary Press Enter lit concn al i PG this segment When Done key to move Number of it Bound Fontes A a af M O Tr Hint use Tab E z Robert L Norton Design No 1 12 24 2009 p Boundary at 11 35 08 Condition M i ay File Model Start of interval End of interval FIGURE 3 soda S conma Within interval conditions Displacement Velocity Acceleration Jerk Ping Boundary Condition Input screen for polynomial functions in program DYNACAM 8 4 5 6 single dwell function shown that what you type in any yellow text box is not accepted until you hit Enter or move off that box with the Tab key or the mouse allowing you to retype or erase with no effect until you leave the text box This is generally true throughout the program Selecting the Next button from the BC screen calculates the coefficients of the poly nomial by a Gauss Jordan reduction method with partial pivoting All computations are done in double precision for accuracy If an inconsistent set of conditions is sent to the solver an error message will appear If the solution succeeds it calculates s v a j for the segment When finished it brings up a summary screen that shows the BCs you selected and the coefficients of the polyno
9. Open it in a word processor FILL IT OUT with your contact information and email it to Arr ange payment and email the sales designofmachinery com file to the address shown 1 Create File for Licensing m 2 Paste Your Unlock Code When you receive the unlock code paste it into the yellow box and click on Activate License to register the Sd program Follow the instructions to Activate License Create Transfer File back up your license files to A Close Unchanged Import License To New Computer other media Be sure to shut the program down before i copying the license files or they will be worthless Paste the Unlock Code here to license the Create License File program then click on Activate License 3 Activate or Close Unchanged Optional Transfer License to New CPU FIGURE A Authorization screen for licensing the program Running the Program At start up a splash screen appears that identifies the program name version revision number and revision date Click the button labeled Start or press the Enter key to run the program A Disclaimer screen next appears that defines the registered owner and allows the printing of a registration form if the software is as yet unregistered A registration form can be accessed and printed from this screen The next screen the Title screen allows the input of any user and or project iden tification desired This information must be provided to proceed and is used
10. imag FFT deg s 2 Piot Options Show Harmonic Lines T Show Envelope Mag FFT deg s 2 IT Show Filled Envelope IT Show Horizontal Grid IT Show Vertical Grid Robert L Norton Design No 2 Ang FFT deg 12 20 2009 at 17 14 41 File Model Real FFT deg s 2 Harmonics Fourier transform screen in program Dynacam Radius of curvature Dynamic Force Principal normal stress Maximum shear stress ROBERT L NORTON model and give you a set of compatible links to start with The cam s SVAJ functions can be applied either to the input link of the linkage the arm carrying the roller or to the output end of the linkage the end effector In the latter case the cam contour will be modified to account for distortion caused by the linkage geometry The geometry of the follower arm as defined on the Profile screen is automatically imported to all linkage screens thus defining the location of link two s ground pivot versus the cam center The global coordinate system origin is at the cam center in all cases and the orientation is as previously defined on the Profile screen DYNACAM does only a kinematic analysis of the linkage train calculating only an gular displacements velocities and accelerations of all the links These can be plotted in DYNACAM Mass properties of the links can be entered on a separate screen but these are not used for dynamic calculations in this program Th
11. and type the angle to which you want to move it in its yellow text box Alternatively you may select a knot with its radio button and then click the mouse on any one of the SVAJ plots at any location that you want that knot to move to A shortcut to select a knot is to Shift Click near the knot you want to activate and this will select its radio button for you Then a Click will move that selected knot Note that because knots must be in ascending order it will refuse to violate their order if you request an inappropriate knot location The plots and extreme values will update immediately unless you uncheck the Autocalc On box at upper right If you are making a large number of knot changes turning off Autocalc will speed the process by suppressing the screen updates It may also avoid tripping error messages engendered by a poor initial distribution of multiple knots until you can get them more or less where you want them before allowing it to recalculate the splines The Back button returns you to the Boundary Condition screen if you wish to change them The Show Splines button will display the basis functions that make up the B Splines Plot Functions returns to the B Spline plots Next returns you to the nput SVAJ Screen Back to the Input Screen Completing a polynomial or spline function returns you to the Jnput SVAJ screen When all segments have been calculated select the Next button on the Input SVAJ screen per haps after copyin
12. created within the program but before doing so will give warning and prompt you to save the data to disk The Save and Save As selections on the File menu prompt you to provide a file name and disk location to save your current model data to disk The data are saved in a custom format and with a three character suffix unique to the particular program You should use the recommended suffix on these files as that will allow the program to see them on the disk when you want to open them later If you forget to add the suffix when saving a file you can still recover the file as described below Note that the default settings of the program do not allow a data file to start the program running when double clicked The reason for this is that double clicking on a file that is not on the same drive as the program s executable file will lock up the pro gram license This is an anomaly of the particular commercial licensing program used This restriction can be overridden on the Preferences screen use Preferences menu but should not be enabled if users of the program might try to run it from a file on an external drive or memory stick This is inevitable if the program is used by students in a server installation If you are a single user on an isolated machine and remember not to double click on a data file on your memory stick or external drive then it will be safe to turn on this feature If you lock the license you can restore it from your license b
13. modifications Retain the existing values on this and the next screen and click on Next until you are back at the Home screen The cam contour data now awaiting export is that of the polydyne or spline dyne cam though the original nonpolydyne contour has been saved in another location so that comparison plots and printouts can be made from the Plot and Print menus if desired Stress Analysis The Stress button on the Home screen becomes available only after either a kinetostatic or dynamic analysis has been done If only the former was done then the kinetostatic forces will be used to calculate the stresses If the Vibration button has been exercised then its more accurate dynamic forces are used for the stress calculation instead The Stress screen is shown in Figure 16 The material parameters for both cam and follower must be supplied but are defaulted to steel for both The appropriate algorithm for surface stress will be used based on the earlier choice of flat or roller follower as described in Chapter 12 of reference 1 If a roller follower is used then you must specify it as cylindrical or crowned and provide the relevant dimensional information A box is provided for the input of a follower weight force if applicable If an external force function was calculated on the S V AJ form then the check box to include it will become available and it can be included or excluded from the stress calculation as desired The calculate button crea
14. to identify all plots and printouts from this program session The second box on the Title screen allows any desired file name to be supplied for storing data to disk This name defaults to Modell and may be changed at this screen and or when later writing the data to disk The third box allows the typing of a starting design number for the first design This design number defaults to 1 and is automatically incremented each time you change the basic design during this program session It is used only to identify plots data files and printouts so they can be grouped if necessary at a later date When the Next button on the Title screen is clicked the Home screen becomes available General User Actions Possible and Behavior of the Program The program is constructed to allow operation from the keyboard or the mouse or with any combination of both input devices Selections can be made either with the mouse or if a button is highlighted showing a dotted square within the button the Enter key DYNACAM 10 USER MANUAL will activate the button as if it had been clicked with the mouse Text boxes are provided where you need to type in data These have a yellow background Double clicking on a text box will select its contents In general what you type in any text box is not accepted until you hit the Enter key or move off that box with the Tab key or the mouse This allows you to retype or erase with no effect until you leave the text box You c
15. B Spline function The next set of choices that you will Tab or mouse click to are the Program pull downs 9 These provide a menu of standard cam functions such as Modified Trap ezoid Modified Sine and Cycloid as well as a large number of specialized functions as described in reference 1 Also included are portions of functions such as the first and If you intend to do any dynamic analysis of your follower train within DYNACAM AND IF you start your motion at a dwell the numerical differential equation solver will fail to converge because when started on a dwell it cannot make any progress with its computtions If you do not intend to do any dynamic analysis shame on you but then you can start the cam design at or within a dwell DYNACAM 10 USER MANUAL second halves of cycloids and simple harmonics that can be used to assemble piecewise continuous functions for special situations The standard double dwell polynomials 3 4 5 and 4 5 6 7 as well as a symmetrical single dwell 3 4 5 6 rise fall function are pro vided as menu picks though they can also be created with a Poly choice and subsequent definition of their boundary conditions After you have selected the desired Program functions for each segment you will Tab or Click to the Position Start and End boxes 10 Start in this context refers to the beginning displacement position for the follower in the particular segment and End for its final position Note
16. DYNACAM 10 USER MANUAL Robert L Norton P E Copyright 2012 Robert L Norton All Rights Reserved Norton Associates Engineeering 46 Leland Road Norfolk MA 02056 USA http www designofmachinery com Contact info designofmachinery com Contents Miodu hossa a N 3 General information Hardware Requirements ind Operating System Requirements Demonstration Version Installing the Software Licensing the Software How to Use This Manual PROGID OPSOM ssaa eaae aaee RA ERA snelshuconasbucchaspnechispaistesbateimeiaichacsbsieeds 4 Running tho PlOQUOIN sacacaccaccatstasucvssneantasnesniacnsdsuauaroccstsetecocsesesoseecscsteueessii ieseisetiicetitdcieieieateensversrstes 5 General User Actions Possible and Behavior of the Program ssssssssssesesesessssssseesesesesestssseneneees 5 HONG SCHON eisecescssscsssechccnccakecnecaaceancascitionianenerewnasenaneupdavdcansvacancevecauds peessouneeasdeneeatespieseansiaaaeaneanece 6 Unifs Menu Examples _ About Menu License Menu User Menu Preferences Menu Help Menu Exiting a Program Creating New Saving and Opening Files File Menu Copying Screens to Clipboard or Printer Copy Exporting Spreadsheet Data Support Creating a Cam 10 Input Data SVAJ Button Polynomial Functions Spline Functions Back to the Input Screen Continuity Check Screen Plotting Data Plot Button Printing to Screen and Disk Files Print Button Creating the Cam
17. End adjacent cam segments are grouped together so thatthe continuity or lack thereof can be easily seen for each ofthe cam functions S V A and J They must be continuous through acceleration 4 for good dynamic performance FIGURE 6 Continuity check screen A 1 1 0 716 635 716 835 oo o oo o loo o je Values between segments Robert L Norton must match through Design No 2 acceleration 12 24 2009 at 18 14 58 File Model Plotting Data Plof Button The Plot button on the Home screen brings up the Plot screen Figure 7 Most variables in this program are plotted on Cartesian axes The cam profile can also be plotted in cylindrical coordinates a polar plot Two arrangements for selecting the functions to be plotted are provided One pro vides preselected collections of functions as shown in Figure 7 and the other allows selection of up to four functions from those available on the pulldown menus as shown in Figure 8 Figures 9 and 10 show other examples of the various plot types available Experiment with the selections of number of functions plot windows and axes to see the variety available The plots can be augmented with gridlines fills lines denoting the cam segments and circles on the joints between cam segments by using the check boxes at upper right of the screen Right clicking on the plot area will bring up a menu that allows other changes to many pl
18. Figure 11 containing lists of variables that may be printed A drop down menu at the top right of this screen can be used to direct the printed output to Screen or Disk This choice defaults to Screen and so must be clicked each time the screen is opened to obtain either of the other options Selecting Screen will result in a scrollable screen window full of the requested data Scrolling will allow you to view all data requested serially This data screen can be copied to the clipboard but this clip or dump will typically show only a portion of the available data i e one screen full Selecting Disk as the output device will cause your selections to be sent to the file of your choice in a tab delimited ASCII text format that can be opened in a spreadsheet program such as Excel You can then do further calculations or plotting of data within the spreadsheet program The Print screen has two modes for data selection One provides preselected sets of two or four variables for printing Drop down menus at the top of the screen allow selection of up to four calculated variables for printing You can print one two or four variables at a time in either mode You can also select other ancillary parameters such as the number of decimal places and the frequency of data to be printed HE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 5 12 20 09 Plot Screen 3 Force kin 3 Velocity 3 Torque
19. Mass Prop Copy Print lt Back Next gt T Select Linkage Type Fourbar Mode 7 Apply SVAJto e Fourber C Sixber C Fourside C Sixside open C crossed G cam arm C Endettector Current angle Please provide the relevant parameter values for your linkage a aT Linkage Parameter Value Unt Link lengths Angle from Line of Link 2 to Roller Arm deg Length of Link 2 in O Length of Link 3 4 FIGURE 19 p Animation Contra L E ns If this window is blank click the Calculate or Redraw button Drag slider to move the linkage Input Data screen for a Fourbar Linkage cam follower train ROBERT L NORTON link Link numbering is standardized with link 1 always the ground link link 2 the link directly driven by the cam and pivoted to ground link 3 a floating coupler or connecting rod and link 4 the output slider in this case running against ground The Offset is the perpendicular distance between the axis of sliding and the pivot O2 The Slider Angle is the angle between the global X axis and the axis of sliding Note that is possible to input a set of linkage data that is impossible to solve as the links may not be able to connect if their lengths are not compatible An error message will appear when the calculation is done if this is the case Once calculated the linkage can be animated by using the Step button to advance it one cam increment at a time or b
20. Offset to 02 Perpendicular to Slide Axis in Slider Angle in Global Coordinate System deg L4 gt X Offset is the perpendicular distance from the slider axis to the pivot O2 4 gt f Animation Control Gaes 1 Renge pa T T E Drag the slider to move the linkage FIGURE 20 Input Data screen for a Fourbar Slider cam follower train Current angle Linkage type Link lengths FIGURE 21 DYNACAM 10 USER MANUAL necting rod link 4 a rocker pivoted to ground at O4 that connects the two couplers link 5 the second coupler and link 6 the output rocker pivoted to ground at O6 The global coordinates of both O4 and O6 must be defined in the cam XY coordinate system Link 4 has two branches the one labeled 4 and shown in black that connects link 3 to O4 and the one labeled 4a in color that connects O4 to link 5 at 745 The angle between branches 4 and 4a which are part of the same link must be defined also It is possible to input a set of linkage data that is impossible to solve as the links may not be able to connect if their lengths are not compatible An error message will appear when the calculation is done if this is the case Once calculated the linkage can be animated by using the Step or Run buttons or by dragging the slider bar at the bottom of the screen to left or right The Mass Prop button goes to the Mass Properties screen described below Sixbar Slider Follower Train
21. Profile Exporting Cam Contour Data Analysis 22 Kinetostatic Analysis Dynamic Analysis Stress Analysis Fourier Transform FFT Linkages FOUTD GL LINKAGE Follower TIGIN esiccsiscssessvstsassecerscsczczseaecoraecoeaecsesenesdescsstsssceissstiascteenctesdeneesiatesieTe 28 Fourbar Slider Follower Train Sixbar Linkage Follower Train Sixbar Slider Follower Train Mass Properties Screen Importing Measured Cam Data Refere NCE Sicona aaaea EAE AAEE NEE RaR S 34 madek rra e a aaa aa a aeledadieeaes 35 Nolo caL E E TA EA E N AA N P E A PEE T 36 History Of PrOGTAM DYNOCGIN ou sicssiicssiicstcetscdescesasscasrezserarasiezst ia ssisesiisenisseritennisonseeen te 36 DYNACAM 10 USER MANUAL Robert L Norton P E Copyright 2012 All rights reserved INTRODUCTION DYNACAM is a cam design and analysis program intended for use by engineers and other professionals who are knowledgeable in the art and science of cam design It is assumed that the user knows how to determine whether a cam design is good or bad and whether it is suitable for the application for which it is intended The program will calculate the kinematic and dynamic data associated with any cam design but cannot substitute for the engineering judgment of the user The cam theory and mathematics on which this program is based are shown in reference 1 Please consult it for explanations of the theory and math
22. Release 10 Rey 1 6 7 12 23 09 Help Calculate lt Back Next gt Velocity for Calculation Single Effective Mass Two Effective Masses Effective Stiffness Use Avg Veloc C Use Max Veloc Mett at Follower DBS m1 at Follower D002 M2ct end ettector UCU ket A Link Parameter Dist from Link Pivot or Input Pin to CG Angle to CG in Local Rotating Coord Sys Mass of Link Second Moment of Mass About CG Stittness of ink 100 FIGURE 23 Mass Properties screen in Dynacam IMPORTING MEASURED CAM DATA Sometimes one needs to reverse engineer an existing cam for which there may be no data available on its design or mathematical functions If a cam profile has been measured with reasonable accuracy those data can be imported to DYNACAM and it will fit an interpolat ing function to approximate the cam s displacement velocity and acceleration functions Figure 24 shows the mport screen Instructions are available from the Help menu on the screen In brief the measured data must be in R Theta coordinates and can be at any uni form angular increments The data must be placed in a text file one pair of tab separated R theta numbers per line DYNACAM will determine how many pairs are in the set when reading the data There should not be any header information in the file just data Three interpolation methods are provided cubic spline cubic spline with Lanzcos smoothing and Fourier series The cubic spline metho
23. ackup copies Selecting Open from the File menu prompts you to pick a file from those available in the disk directory that you choose If you do not see any files with the program s suffix use the pulldown menu within the Open File dialog box to choose Show All Files and you will then see them They will be read into the program properly with or without the suffix in their name as long as they were saved from the same program Copying Screens to Clipboard or Printer Copy Any screen can be copied as a graphic to the clipboard by using the standard Windows keyboard combo of Alt PrintScrn It will then be available for pasting into any compatible Windows program such as Word or Powerpoint that is running concurrently in Windows and print from that program This is the recommended approach to printing hard copy Exporting Spreadsheet Data On the Home screen the File pulldown menu has an Export selection within which is a selection for Spreadsheet This choice will generate a tab delimited text file containing all the data calculated in DYNACAM It is essentially a memory dump Data are arranged in labeled columns for identification and a header is written that identifies the model data This file can be opened in Excel See the section Exporting Cam Contour Data for instructions on exporting a cam profile Export Spreadsheet should not be used for that purpose Support Support is available only to licensed users Please direct questions ab
24. an move between available input fields with the Tab key and back up with Shift Tab on most screens If you are in doubt as to the order in which to input the data on any screen try using the Tab key as it will take you to each needed entry field in a sensible order You can then type or mouse click to input the desired data in that field Remember that a yel low background means typed input data is expected Boxes with a cyan background feed information back to you but will not accept input Other information required from you is selected from drop down menus or lists These have a white background Some lists allow you to type in a value different than any provided in the available list of selections If you type an inappropriate response it will simply ignore you or choose the closest value to your request Typing the first few letters of a listed selection will sometimes cause it to be selected Double clicking on a selectable item in a list will often provide a shortcut and sometimes a help screen LEAVING A SCREEN Note that when you enter a screen and begin changing values the new data will only be incorporated in your model if you Calculate on that screen and exit with the Next button If you have changed values in text boxes but have not yet recalculated the model and you exit the screen with the Back button then the old values not your changed ones will be preserved and the model will remain unchanged Re member that the program think
25. ardized with link 1 always the ground link link 2 the link directly driven by the cam and pivoted to ground link 3 a floating coupler or connecting rod and link 4 the output link in this case pivoted to ground Ground pivots are labeled O with n link number The coordinates of pivot O4 must be supplied in the cam XY coordinate system Note that is possible to input a set of linkage data that is impossible to solve as the links may not be able to connect if their lengths are not compatible An error message will appear when the calculation is done if this is the case Once calculated the linkage can be animated by using the Run or Step buttons or by dragging the slider bar at the bottom of the screen to left or right The Mass Prop button goes to the Mass Properties screen described below Fourbar Slider Follower Train Figure 20 shows the input screen for a fourbar slider linkage The Fourslide Mode defines the kinematic circuit of the linkage which can be either open or crossed as desired For a definition of these terms see reference 2 The Angle from Line of Link 2 to Roller Arm parameter defines the included angle between the kinematic link 2 and the arm ra dius to the roller The link lengths are always defined as the pin to pin distances of each Choose circuit gl DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 Linkage Screen Help Calculate Redraw Zoom Out Normal Zoom An Step Run
26. bled at this location to allow you to determine the values of boundary conditions as you work your way through a piecewise function Polynomial Functions If any of your segments specified a Poly motion clicking the Calculate button will bring up the Boundary Condition screen shown in Figure 3 The cursor will be in the box for Number of Conditions Requested Type the number of boundary conditions BCs desired which must be between 2 and 50 inclusive When you hit Enter and you must hit Enter the rest of the screen will activate allowing you to type in the desired values of BCs Note that the start and end values of position that you typed on the Input SVA screen are already entered in their respective boundary condition boxes at the beginning and end of the segment Type your additional end of interval conditions on V A J and P as desired If you also need some additional BCs within the interval click or tab to one of the boxes in the row labeled Local Theta at the top of the screen and type in the value of the angle at which you wish to provide a BC That column will activate and you may type whatever additional BCs you need The box labeled Number of Conditions Selected monitors the BC count and when it matches the Number of Conditions Requested the Next button becomes available Note ROBERT L NORTON DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rey 1 6 7 12 23 09 Help Clear Bounds Copy Print lt Back
27. ctions to choose from EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 5 12 20 09 Plot Screen Choose or i Help All Segments Velocity Jerk E 3 RePlot Clear Next gt Plot Type ti wif change the e csan Foe c Displacement Velocity Acceleration Jerk eusor ons plot items T Par Options f Pi fed Cam Follower Parameters I Show Horizontal Grid rom these Force kin n Velocity pe T Show Vertical Grid Ce ee T Show Fills drop down Ea A I Show Bers I Show Segment Lines T show Circles Set All Dec Places 3 x lists Displcmnt deg a H These boxes show max Model and min parameters 3 values are listed 2 vo EEE oo Min degis 2 here 6675550 degis 3 E3 Jerk E 3 degis 3 EE E A degis 3 E3 1 1 180 210 a weg deg s 3 E3 FIGURE 8 An example of four plots in separate windows and individual dropdown menus to choose plot items DYNACAM 10 USER MANUAL D P by R pyright 2009 Release 10 Rev 1 6 0 09 Plo iol xj Choose Help All Segments Phi velocity gt Rho gt Accel RePlot Clear Next gt Plat T Functions Windows rA number of e SRR CP Le C26 FIE 1G eH bsy muti Press Angle Velocity Radius of Curvature Acceleration eursor off X func tions Current Model Parameters aE P Pio
28. ds are preferable if dwells are present because the Fourier series will add ripple to dwells But the Fourier method may do a better job of smoothing noisy data The desired angular increment at which the interpolation is to be done should be se lected from the drop down at the left before importing data The units system should also be preselected The mport Data button will open a browser to find the file import it and display the raw contour as an S diagram in the upper window The Fit Functions button will do the interpolation First the selected function is fitted to the imported data then it is differentiated analytically not numerically to get velocity and acceleration These functions are then resampled at the chosen delta theta increment for display and export The Show Data button will display the original imported data and the displacement function fitted as shown in Figure 24 The Show Derivatives button will show the veloc ity and acceleration functions from the interpolated curve as shown in Figure 25 Save Functions and Exit stores the interpolated functions in the normal locations for DYNACAM data making them available for plotting printing and further calculation Exiting this screen return you to the Home screen where the SVAJ button will be grayed out so as to prevent inadvertent overwriting of the imported data All other pro gram functions can be applied to the interpolated cam functions ROBERT L NORTON Interpolati
29. e 21 smoothed torque 22 spline 15 splinedyne 25 Start New or Accumulate 22 Starting Angle 11 Stress button 25 screen 25 Support 9 T Tab key using 10 Title screen 5 Translating 11 U units 7 user actions possible 5 User Menu 8 V vibration analysis 23 button 23 DYNACAM 10 USER MANUAL Appendix THE HISTORY OF PROGRAM DYNACAM I wrote the first version of this program in 1979 when working as a senior engineer at Polaroid Corp The graphics minicomputer had recently been invented and Polaroid had purchased an early example a Hewlett Packard Recognizing that the company needed a better means to design cams for their production machines and wanting to learn how to program the HP I wrote an interactive program for cam design and called it ANACAM This program was left behind when I went on to teach mechanical engineering at WPI in 1981 WPI had recently purchased five Apple II computers which were among the vanguard of graphics microcomputers just becoming available at the time These were then the only graphics capable computers at the school The school had a Vax mainframe for all general computation but graphics terminals for it were still in the future The Apples were sitting unused in a locked classroom and I asked to use them To learn how to program them and to create teaching tools for kinematics I rewrote a much reduced version of ANACAM on the Apple II and renamed it DYNACAM The Apple II version was fa
30. e defined as if it were a cam displacement function with units of force instead of length When calculated the force data is stored for later superposition on the follower s dynamic forces due to motion When External Force is checked a dialog box pops up with information on how to use it Another Tab should put your cursor in the box for the Beta segment duration angle of segment 7 Type any desired angle in degrees Successive Tabs will take you to each Beta box to type in the desired angles The Betas must of course sum to 360 degrees If they do not a warning will appear As you continue to Tab or click your mouse in the appropriate box if you prefer you will arrive at the boxes for Motion selection 8 These boxes offer a pulldown selec tion of Rise Fall Poly Dwell and Spline You may select from the pull down menus with the mouse or you can type the first letter of each word to select it Rise Fall and Dwell have obvious meanings The Poly choice indicates that you wish to create a customized polynomial function for that segment and this will later cause a new screen to appear on which you will define the order and boundary conditions of your desired polynomial function The Spline choice indicates that you wish to create a customized B Spline function for that segment and this will later cause a set of new screens to ap pear on which you will define the boundary conditions order and knot locations of your desired
31. e the effective mass and effective spring values for the dynamic models in the program these data will be automatically transferred to those screens The raw data will be exported to the linkage files for import to other programs Choose circuit for links 1 2 3 4 Choose circuit for links 1 4a 5 6 HE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 Linkage Screen 3 Help Calculate Redraw Zoom Out Normal ZoomIn Step Run Mass Prop Copy Print lt Back Next gt Autocalc p Select Linkage Type _ Stage 1 Mode Stage 2 Mode P Apply SVAJ to p Cam Angle F on C Fourbar C Sixbar C Fourside Sixside open C crossed open C Crossed G CamArm C EndEttector E deo Please provide the relevant parameter values for your linkage Linkage Parameter Length of Link 3 Length of Link 4 Fixed Pivot 04x Link lengths Fired Piot Oty Distance O4 to 145 in Link 4 Arie to uS win nk Length of Link 5 Offset Slider Angle Animation Control lt Start sE fer i Drag the slider to move the linkage FIGURE 22 Input Data screen for a Sixbar Slider cam follower train Current angle Link length Slider angle is the angle between the slider axis and the X axis here 90 Offset is the perpendicular distance from the slider axis to the pivot O4 DYNACAM 10 USER MANUAL DYNACAM Plus by R L Norton Copyright 2009
32. eadsheet option and you will get every piece of data that DYNACAM has calculated for this cam But don t complain when you pick the wrong columns of data to give to the shop and your cam doesn t work ANALYSIS Kinetostatic Analysis When the cam has been sized the Dynamics button on the Home screen will become available This button brings up the Dynamics screen shown in Figure 13 Text boxes are provided for typing in values of the effective mass of the follower system the ef fective spring constant and spring preload for a force closed follower and a damping factor By effective mass is meant the mass of the entire follower system as reflected back to the cam follower roller centerline or cam contact point as defined in Chapter 8 of reference 1 Any link ratios between the cam follower and any physical masses must be accounted for in calculating the effective mass Likewise the effective spring in the system must be reflected back to the follower The damping is defined by the damping ratio C as defined for second order vibrating systems See Chapters 8 and 9 of reference 1 for further information The journal diameter and the coefficients of friction are used for calculating the fric tion torque on the shaft The Start New or Accumulate switch allows you to either make a fresh torque calculation or accumulate the torques for several cams running on a common shaft The energy information in the window can be used to calculate a flywhe
33. el needed for any coefficient of fluctuation chosen as described in Chapter 9 of reference 1 The program calculates a smoothed torque function by multiplying the raw camshaft torque by the coefficient of fluctuation specified in the box at lower right of the screen Dynamic Analysis True dynamic vibration analysis as described in Chapter 10 of reference 1 is available from the Vibration button on the Home screen once the kinetostatic calculation has been done This brings up the Model Type selection screen shown in Figure 14 Four dynamic models of the types described in Chapter 10 of reference 1 are available from this screen ROBERT L NORTON Select type of joint closure Must select Ext Force on SVAJ screen for this EEI DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 8 12 27 09 Help Calculate Replot Copy Print lt Back Next gt Autocale p Joint Closure Fon Force closed C Form Closed r Torque Calculation Options Start Fresh C Accumulate TF Add External Force Kinetostatic Force and Torque dinates Dynamic System Properties Y Coordinate Effective Mass Tam Spring Parameters Mass reflected to follower 43 2 Spring Rate Spring Preload z 346 Spring reflected to follower 643 Force kin Ib Follower force Assumed value Coefficient e Y Moa Calculated value ma Friction Torque Parameters Cam Journal Die
34. ematics involved The authors and publishers are not responsible for any damages that may result from the use or misuse of these programs DYNACAM is one member of a family of programs by this author that share a com mon kernel for the overhead actions such as printing plotting etc In this manual you will sometimes see references such as these programs will which means that these features are common to the family DYNACAM also can generate files for export to several of these programs e g FOURBAR SIXBAR SLIDER GENERAL INFORMATION Hardware Requirements These programs need a Pentium or better processor DYNACAM is large and uses sig nificant computer resources A minimum of 1GB of RAM is desirable DYNACAM may require that all other applications be shut off in order to run in a computer with otherwise insufficient memory A CD ROM drive is needed as is a hard disk drive Operating System Requirements DYNACAM 10 is written in Microsoft Visual Basic 2008 and works on any computer that runs Windows XP Vista Windows7 Demonstration Version The demonstration version of this program is downloadable from http www designofmachinery com DYNACAM 10 USER MANUAL and allows up to 10 runs over a period of 30 days from first installation Certain features are disabled in the demonstration version such as the ability to open or save files and to output cam profile or linkage coordinate data It does come with severa
35. ense for the program click on the I want to buy it now but ton on the Home screen This brings up the Authorization screen as shown in Figure A Please follow the instructions in Figure A and on the Authorization screen Be sure to back up the license files to external media so you can recover the program from a disk crash or reformat How to Use This Manual This manual is intended to be used while running the programs To see a screen referred to bring it up within the program to follow its discussion PROGRAM OPERATION All programs in the set have similar features and operate in a consistent way For exam ple all printing and plotting functions are selected from identical screens common to all programs Opening and saving files are done identically in all programs These common operations will be discussed in this section independent of the particular program Later sections will address the unique features and operations of each program ROBERT L NORTON Click on this button to create a HE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 5 12 20 09 text file that encapsulates the License Code shown X Open this text file in Word n Wordpad or other program and DO THE FOLLOWING TO UPGRADE YOUR LICENSE for DYNACAM Plus add your contact information License Code Also check the version of the Use the Create License File button below to create an order form as a text file program you want to buy
36. ey are used only for the lumped model approximations on the Dynamics and Vibration screens Rather the linkage ge ometry and mass data along with all the cam SVA data can be exported in a text file that in turn can be imported into a linkage analysis program such as FOURBAR SIXBAR or SLIDER for further analysis Those programs will do a complete kinematic and dynamic analysis of the linkage using the SVA cam functions from DYNACAM to drive it Fourbar Linkage Follower Train Figure 19 shows the input screen for a fourbar linkage The Fourbar Mode defines the kinematic circuit of the linkage which can be either open or crossed as desired For a definition of these terms see reference 2 The Angle from Line of Link 2 to Roller Arm EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 Help lt Back Next gt Select C Select Fourbar Linkage Follower Train Watts II Sixbar Linkage Follower Train Fourbar linkage an Select C Select C Watts Il Sixbar Slider Follower Train Fourbar slider FIGURE 18 Linkage Type selection screen in Dynacam Sixbar linkage Sixbar slider Linkage type DYNACAM 10 USER MANUAL parameter defines the included angle between the kinematic link 2 and the arm radius to the roller This is often zero but can be nonzero if desired as shown in the figure The link lengths are always defined as the pin to pin distances of each link Link numbering is stand
37. g it to the clipboard and pasting it into a Word file to serve as a record of your design Selecting Next will bring up the Continuity Check screen as shown in Figure 6 Continuity Check Screen The screen in Figure 6 provides a visual check on the continuity of the cam design at the segment interfaces The values of each function at the beginning and end of each segment 1 e between the segments are grouped together for easy viewing The fundamental law of cam design requires that the S V and A functions be continuous over the entire interval This will be true if the boundary values for those functions shown grouped as pairs are equal If this is not true then a warning dialog box will appear when the Next button is clicked It displays any errors between adjacent segments in both absolute and percentage terms You must decide if any errors indicated are significant or are due only to computational round off error The message will give information to make this judgment If the error is very small and can be safely ignored the message will say so Cancel will return you to the Input Data screen to correct the problem and OK will take you to the Home screen DYNACAM 10 USER MANUAL RE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rey 1 6 7 12 23 09 Check Scr xj Help iew Copy Print lt Back Next gt Resulting Boundary Values at Segment Interfaces The function values atthe beginning and end of Segment
38. grees or radians Examples The Examples pulldown menu on the Home screen provides a number of example cams that will demonstrate the program s capability Selecting an example from this menu will cause calculation of the cam and open a screen to allow viewing the results In some cases you may need to hit a button marked Calculate or Run on the presented screen to see the results Examples can also be accessed from a drop down menu from within the input SVAJ screen DYNACAM 10 USER MANUAL About Menu The About pulldown menu on the Home screen will display a splash screen containing information on the edition and revision of your copy of the program The Disclaimer and Registration form can also be accessed from this menu License Menu The License pulldown menu on the Home screen gives information on the program s li cense status It also allows the license to be transferred to another computer or upgraded to obtain additional features User Menu The User pulldown menu on the Home screen gives information on the user name com puter name filename and location of saved data Preferences Menu The Preferences pulldown menu on the Home screen lets you set the defaults that will obtain when the program opens These are saved to a text file in the folder where the program file resides This file is read each time the program opens and rewritten at your request from the Preferences menu See the Preferences Help File in the
39. h the explanation as if you were typing your data into an initially blank Input SVAJ screen If you use the Tab key it will lead you through the steps needed to input all data as indicated by the circled numbers in Figure 2 On a blank Input screen Tab first to the Cam Omega boxes in the upper left corner 1 and type in the speed of the camshaft in rpm or rad s as you prefer Tab again or mouse click if you prefer to the Number of Segments Input Screen x Help View Calculate All Clear Segments Clear All Copy lt Back Next Cam Data Cam Omega e aE en c cc No of Segments Clear on EE oss Detta Theta deg ho x Folower C Translating Oscillating Starting Angle TOT es T External Force Function Follower Motion eae Pull down me for examples a prr 3 l You can Se a z plot or print each Select Select segment s these these data to a inspect results as you go C External Force Robert L Norton Design No 1 12 20 2009 at 16 47 20 File Modei These can only be changed in the Professional Edition Click Calculate for each segment S VA J Input screen for program DYNACAM 2 ROBERT L NORTON box 2 and type in any number desired between and 24 That number of rows will immediately become visible on the nput screen If the Clear on Opening checkbox is checked changing the number of segments will erase all content
40. in Fixed Pivot Oy 400 n rol Drag the slider to move the linkage Input Data screen for a Sixbar Linkage cam follower train ROBERT L NORTON the two couplers link 5 the second coupler and link 6 the output slider running against ground The global coordinates of O4 must be defined in the cam XY coordinate system Link 4 has two branches the one labeled 4 and shown in black that connects link 3 to O4 and the one labeled 4a in color that connects O4 to link 5 at 745 The angle between branches 4 and 4a which are part of the same link must be defined Offset is the per pendicular distance between the axis of sliding and the pivot O2 The Slider Angle is the angle between the global X axis and the axis of sliding It is possible to input a set of linkage data that is impossible to solve as the links may not be able to connect if their lengths are not compatible An error message will appear when the calculation is done if this is the case Once calculated the linkage can be animated by using the Run or Step buttons or by dragging the slider bar at the bottom of the screen to left or right The Mass Prop button goes to the Mass Properties screen described below Mass Properties Screen Figure 23 shows the Mass Properties screen The CG locations and mass properties of each link may be entered here Proper units must be used The stiffness parameters for each link can also be entered When calculated this screen will comput
41. irly crude menu driven memory limited and slow but it served the purpose as a teaching tool along with other programs I wrote for student use such as FOURBAR FIVEBAR SLIDER SIXBAR ENGINE and MATRIX Over the next decades computers went through huge changes WPI followed the trends migrating to Macintosh DOS and Windows in all its gestations 95 98 2000 XP Vista 7 Each time the school switched computers and operating systems I was forced to rewrite these programs so that students could still use them Languages used were Apple Basic DOS Basic QuickBasic Visual Basic 4 through 6 and now Visual Studio VB NET As the program was rewritten it also grew with the addition of features and capabili ties Some of these were the result of student projects done at WPI Those students are credited in the program s splash screen The biggest changes came about as a result of a sabbatical done at The Gillette Company in Boston in 1996 where I found a number of my former students using their student copy of DYNACAM to actually design cams for production machines DYNACAM was a very limited menu driven DOS program at the time For example it only handled translating followers and most of Gillette s cams have oscillating followers So I began adding features while working at Gillette on that sab batical and took great advantage of interactions with their engineers to define what they needed the program to do They also served as my beta
42. l example files that can be opened in the demonstration version It also has a few cam profile files that can be used to test the process of importing the cam profile to a CAD system such as Solidworks or ProEngineer Instructions for doing so with those programs are also included in the download package If you wish to have the fully functional program you must register it and pay the license fee defined on the Registration screen Installing the Software The install file contains the executable program files plus all necessary Dynamic Link Library DLL and other ancillary files needed to run the programs Run the DYNACAM__ Install exe file to automatically decompress and install all of its files on your hard drive Accept all defaults as presented When installed the program name will appear in the list under the Start button s Program menu after installation and can be run from there See the Readme file included with the installation package for information on licensing the program Note that it can only be installed by an administrator on that computer Also for it to run properly by a user who does not have administrator privileges the folder Program Files Design of Machinery DYNACAM10 must have write privileges set for all users If it is installed under Vista or Windows 7 certain properties must be set on the DYNACAM exe file See the instructions with the install package for details Licensing the Software If you want to buy a lic
43. lt values The end time s value defaults to and cannot be set to less than two cycles of the camshaft but can be set longer Thus the calculation solves for at least 2 cam evol tions and displays the results in plots of displacement error s x x and along with their extreme values The data is saved only for the second revolution in order to discard the effects of any numerical convergence start up transients The center bar shows calculated values of the system natural frequencies natural periods and various dynamic ratios as described in of reference 1 Clicking the Next button at this point returns you to the Home screen POLYDYNE AND SPLINEDYNE CALCULATION The Vibration screen provides a check box to make a polydyne or splinedyne cam of the current design Checking it brings up a Industrial models Automotive models FIGURE 14 EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 091 Help Select M One Mass SDOF Model Spring at cam follower DYNACAM 10 USER MANUAL lt Back Next gt Select Two Mass SDOF Model Spring at cam follower Select C One Mass SDOF Model Spring at end effector Two Mass SDOF Model Spring at end effector 1 mass 1 DOF models 2 mass 1 DOF models Select Vibration Model screen in program DYNACAM Simulation Results Vibration Model Simulation Screen Print lt Back Next gt Plat Options
44. mial equation that resulted as shown in Figure 4 You may at this point want to print this screen to the printer or copy and paste it into another document for your records You will only be able to reconstruct it later by again defining the BCs and recalculating the polynomial Spline Functions If any of your segments specified a Spline motion clicking the Calc button will bring up the same Boundary Condition screen shown in Figure 3 that is used for polynomial functions These are defined in exactly the same way as described for polynomials in the preceding section Once you finish selecting boundary conditions for your spline and hit the Next but ton it takes you to the Spline Function screen shown in Figure 5 This screen shows the current segment the number of boundary conditions that were selected and requires DYNACAM 10 USER MANUAL Bl Polynomial Data x Copy Print Next gt Boundary Conditions Selected and Resulting Displacement Equation Coefficients Coefficients for S Equation Boundary Conditions Selected with ThetaBeta as Variable Boundary Conditions Imposed Equation Resulting Function Theta Beta Boundary Cond Exponent Coefficient Disp 0 0 a o 0 000 Veloc 0 o o 1 0 000 Accel 0 0 a 2 0 000 Polynomial Disp 50 1 1 3 204 051 Cocthicients Veloc 50 1 0 4 597 153 Accel 50 1 o 5 588 153 Disp 20 04 3 6 194 051 Boundary Robert L Norton Conditions Applied Design No
45. nters The check box labeled Zero Reference phase shifts the cam contour to either cam zero or machine zero and redisplays it In the case of an oscillating arm follower the cam contour is reoriented to put the keyway at the selected o clock position For a translating follower the follower is kept in a fixed orientation along the x axis and the keyway rotated to the correct relative position These phase shifts incorporate the start angle follower angle and keyway location The magenta radial lines that form pieces of pie within the base circle represent the segments of the cam If the cam turns counterclockwise the radial lines are numbered clockwise around the circumference and vice versa The cam profile is now ready for export Whether the Primary or Conjugate radio button was selected when Next was clicked determines which of those two cam contours will be the one exported So to generate profile data for a pair of conjugate cams requires sequential calculation and export of their respective data to separate files The state of the Cam Surface radio buttons at the time Next was clicked also dictates which cam surface will be exported Generating both cam surfaces also requires sequential calculation and export of data Only one set of cam surface contour data is stored in memory at a time The cam profile for a radial cam can be displayed at any time from the Home screen with the Profile button So for creation of multiple cam surfaces
46. o deg point as the last 360 deg data point This requires 361 data sets for 1 deg increments Other CAD systems want to complete the circle themselves and require the data to stop short of the last point This requires 360 data sets for 1 deg increments This mode can be set in the program to match the CAD system of choice by using the Help Preferences panel on the Home screen DYNACAM 10 USER MANUAL a CAD model then machine zero is probably the better choice for export in order to get it properly phased with other cams in the system The data exported for radial cams is only provided in cartesian coordinates in order to avoid confusion and possible error by the manufacturer that could occur if they were given polar coordinates especially for oscillating followers or for translating followers with offsets For compatibility with 3 D CAD CAM systems three coordinates are pro vided x y and z with z set to zero for radial cams The z column is easily deleted in a spreadsheet if not needed The exported data for barrel and linear cams is in 3 D cylindrical coordinates R A z with R set to a constant value equal to the prime cylinder radius is the cam angle for each data point and will not be equispaced for oscillating arm followers or for surface data of any cam and z is the axial follower displacement at R 1 If you insist on being ornery and want to have your cam cutter data in some other form choose the Spr
47. oefficient of fluctuation 22 of friction 22 continuity check 15 copying to clipboard 9 Creating a Cam 9 creating new files 9 D Delta Theta 11 demonstration version 3 dynamic forces 25 Dynamics button 22 screen 23 Examples 7 examples 7 exporting cam contour 21 SVA data 27 external force 11 25 F follower angle 20 arm 20 dynamics 22 23 25 offset 20 oscillating 20 translating 20 weight 25 Index Fourier transform 25 screen 25 friction torque 22 fundamental law 15 H hardware requirements 3 Help Menu 8 how to use this manual 4 l importing measured cam data 32 inner surface outer surface 21 Input Data 10 installing the software 4 J journal diameter 22 K kinetostatic forces 25 L License Menu 8 licensing the software 4 linkage 27 fourbar 28 fourbar slider 29 sixbar 30 sixbar slider 31 M mass properties 27 screen 32 motion force option 11 N number of segments maximum allowed 10 O ODE solver 23 offset 20 opening a file 9 operating system requirements 3 Oscillating 11 P plotting data 16 polydyne 25 polynomial 11 coefficients 13 completing 15 solution method 13 polynomial functions 12 13 Preferences Menu 8 pressure angle 20 prime circle 20 printing 19 program operation 4 Q quitting the program 8 radii of curvature 20 roller radius 20 running the program 5 S saving data 9 Select Dynamic Model screen 23 Show Cam 21 Show Conjugat
48. on methods EEI DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev i 6 12 23 09 Import Data Screen Help Import Data Fit Functions Show Data Show Derivatives lt Back Save Functions and Exit Coordinates Follower Type Interpolation Method Save Displacement Data as Normalization PolarR T Cartesian XY Translating Oscillating LanzcosC S Cubic Spline C Fourier Series interpolated C Raw Data I Remove DC Component Calculation Data x y coordinates Imported Displacement Data at Imported E contour E E T 00 Interpolated Displacement Function T Show Data Points T Show Fills I show Horizontal Grid amp I Show Vertical Grid g Interpolated H function Robert L Norton Design No 3 12 24 2003 at 18 09 51 File Model FIGURE 24 Import Data screen in Dynacam Probably the best way to utilize this feature in DYNACAM is to use the interpolated derivatives to determine what functions may have been used in the original cam design and where the dwells start and stop With this information a new cam can be designed using DYNACAM s built in functions This approach will result in a more accurate and dynamically superior cam than will using the interpolated functions as is OTHER All the data calculated at each stage is saved and becomes available for plotting printing or exporting to disk See General Program Operation for information on New Open Save
49. or conjugates of radial cams it is necessary to revisit the Profile screen Clicking Next on the Profile screen re turns you to the Home Screen where a dialog box appears with instructions on exporting the cam contour data for manufacturing Exporting Cam Contour Data There is more than one way to get the cam contour data out of DYNACAM for manu facturing but only one of these is set up specifically for that purpose and it is strongly recommended that you use it in order to avoid errors in manufacturing On the Home screen the File pulldown menu has an Export selection within which are selections for Spreadsheet and Profile File Export Profile is the recommended choice Depending on the type of cam designed radial barrel or linear and the type of follower roller or flat the selections under Profile will vary They typically will provide one or several choices that may include surface coordinates cutter centerline and roller follower centerline coordinates as appropriate These data can be output as referenced to cam zero or to machine zero as desired If these two angles differ it is probably because machine zero is within a mo tion segment of the cam In that case one should NOT begin cutting the cam contour at machine zero which is within a motion However if one is importing the profile data to Some CAD programs require cam profile data to complete the circle which requires that the data repeat the first zer
50. ot parameters such as color to be made A cursor can be turned on at upper right and it will display the coordinates of the functions as the cursor is hovered over the plotted line From the Plot screen you may copy to the clipboard for pasting into another ap plication by using Alt Printscreen Next returns you to the Home screen ROBERT L NORTON 009 Release 10 Rev 1 6 0 09 Plo A ioj x Help All Segments R Select Function 1 Select Function 2 Select Function 3 Select Functions RePlot Clear Next gt Piot Type Functions Windows Axes E conesen raw 1e2 ere2 a C1 mm z Fuser on x Displacement Velocity Acceleration Jerk x Press Angle Velocity Radius of Curvature Acceleration Sunak Mod Ea Cam Profile X coord Y coord Radius Theta versus Cam zero k Cam Profile X coord Y coord Radius Machine zero ff Horizontal Grid surf Y surf X Cutter Y Cutter versus Cal Vertical Grid Click on any Radius Theta versus Machine zero raz Displacem orce ity Torque b Fy Es Dynamic Response S X X X dot X double dot Sk Bee item in this Show Segment Lines A show craes list of combos Set AlDec Pieces 3 Z to see the Funcion 1 vo lt ps Min ics deg p Function vo M p Function3 n N 2 2 p Function w G r r EE c2o s E FIGURE 7 The Plot screen has a collection of preset conbinations of fun
51. out program use or problems by emailing norton designofmachinery com GQ G 2 oS FIGURE 2 HE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 5 12 20 09 DYNACAM 10 USER MANUAL CREATING A CAM Initially only the SVAJ and Quit buttons are active on the Home screen Typically you will start a cam design with the SVAJ button but for a quick look at a cam as drawn by the program one of the examples under the Example pulldown menu can be selected and it will draw a cam profile If you activate one of these examples when you return from the Cam Profile screen you will find all the other buttons on the Home screen to be active We will address each of these buttons in due course below Input Data SVAJ Button Much of the basic data for the cam design is defined on the Input SVAJ screen shown in Figure 2 which is activated by selecting the SVAJ button on the Home screen When you open this screen for the first time it will be nearly blank with only one segment s row visible Note that the built in examples can also be accessed from this form at its upper right corner If you had selected an example cam from the pulldown menu on the Home screen making the Input SVAJ screen nonblank and want to start a new model please now select the Clear All button on the Input SVAJ screen to zero all the data and blank the screen in order to better follow the presentation below We will proceed wit
52. present in the segment rows Leaving it unchecked allows one to add or subtract segments while preserving existing data Tab or click to the Delta Theta pulldown 3 and select one of the offerings on the menu No other values than those shown may be used Next select either Translating or Oscillating for the follower motion 4 Choose either Translating or Oscillating for the follower motion Note that the units of the Start and End values change from length units for translating followers to degrees for oscillating followers The Starting Angle box 5 allows any value to be typed to represent the machine angle on the timing diagram at which you choose to begin the first segment of your cam i e where you choose cam zero Unless the timing diagram places machine zero within a motion event this can be left as zero making cam zero the same as machine zero the default If machine zero is within a motion rise or fall you cannot start the cam design at that point Also you should always place cam zero at the beginning of a motion not at or in a dwell The External Force check box and the Motion Force option buttons 6 are provided for situations in which the cam follower is subjected to a substantial external force during operation such as in a compactor mechanism Checking this box temporarily converts the cam design program into a force time function design program in which the shape of the force time or force angle function can b
53. program for more information Help Menu The He p menus on some screens provide on line access to this manual as well as specific instructions for various functions within the screens Help files download from a website and run automatically in their own browser window An instructional video that runs in Windows Media Player or any similar program is also accessible from the help menu on the Home screen You must be connected to the internet to access the on line help and videos Exiting a Program Choosing either the Quit button or Quit on the File pulldown menu on the Home screen will exit the program If the current data has not been saved since it was last changed it will prompt you to save the model using an appropriate suffix It will ask you to confirm that you want to quit If you choose yes the program will terminate and any unsaved data will be gone at that point Note that the Home screen has a check box at its upper right corner that can be used to close the program This will close the program immediately without asking you to save data or confirm the action Creating New Saving and Opening Files File Menu The standard Windows functions for creating new files saving your work to disk and opening a previously saved file are all accessible in licensed installations from the pull down menu labeled Fi e on each program s Home screen Selecting New from this menu ROBERT L NORTON will zero any data you may have already
54. r roller radius if any and cutter radius can be typed into their respective boxes For a translating follower its offset and angle of translation versus the positive x axis can be specified For an oscillating fol lower the location of the arm pivot and the length and rotation direction of the arm must be provided When a change is made to any of these parameters the schematic image of cam and follower is updated Select the Calculate button to compute the cam size parameters and the cam contour The max and min pressure angles and radii of curvature are shown at bottom right and a more detailed summary can be seen by using the Derails button Radial cams can be animated but barrel and linear cams are displayed statically In a radial cam profile drawing an arrow indicates the direction of cam rotation The initial position of a translating roller follower at cam angle 9 0 is shown as a filled circle Show cam contours Shift image left right Adjust EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 15 5 12 20 09 Cam Profe Screen animation Help Calculate Redraw Zoo Out Normal ZoomIn Ste Run Details Copy lt Back Next gt uae YC Sa Tig cara speed here M on primary Conjugate Cam Surtace Follower Path C Cutter Path fies 1 Sider Range jooo gt femme Cs Cam Rotation a Prime Radius Initial follower posi
55. s you changed your mind if you Back out of a screen and assumes you do not want to keep any changes made therein If you Calculate then the changes are in the model When you leave via the Next button the program as sumes you are done with that task and updates other necessary information accordingly HOME SCREEN All program actions start and end at the Home screen It has several pull down menus and buttons File Screens View Units Examples License User Help Preferences About The View menu allows the home screen to be shown in one of three modes Full Screen Compact or Menus Only as shown in Figure 1 The Screens menu allows access to the buttons shown on the Compact and Full Screen modes which is the only access to them in Menus Only mode The View menu also allows all screens to be Centered or Floated on opening and can force them to be Topmost or not as you choose The defaults when the program is first run are Home is Full Screen and all other forms are Centered and Topmost The Prefer ences menu allows these and other choices to be set and remembered when the program closes It will then wake up on subsequent runs in the preferred modes you previously set Units Menu The Units menu defines several units systems to choose from It is your responsibility to ensure that the data as input are in some consistent units system Units conversion is done within the program The Units menu selection that you make will convert any da
56. t Options Selected Cam Follower Parameters I Show Horizontal Grid windows Parameter Value Unit Phi Velocity Rho Accel I Show Vertical Grid 150 F T Show Fills and axes ape ny Sereeete TE stow ar T Show Segment Lines TT Show Circles Set Al Dec Places 3 x 100 here L TIT TTTT thot g Phi iio cae Max Doo aaa deg mn Eassa 3 p p DA os Seay I co These boxes ee in EB oo _ show max Model pee r e NEO sos and min parameters 200 Rho values are listed here J 2000 r aaa degis 2 p degis 2 degi z FIGURE 9 An example of superimposed plots in multiple windows with multiple axes per window P by R L Norton Copyright 20 ease 10 Rev 1 6 0 09 Plo E loj x Choose E Help gt z RePlot Clear Next gt Plt T Functions Windows a polar or le eee G Polar es Ce e 1 er C Mut cartesian Current Model Parameters Selected Cam Follower Parameters Piot Options F Finer Grid plot here IT Show Vertical Grid T Filone ten T Show Bars IT Show Segment Lines T Show Circles Set Al Dec Places 3 x Model parameters are listed here Linkage Type FIGURE 10 Polar plot of the cam profile ROBERT L NORTON Printing to Screen and Disk Files Print Button Selecting the Print button from the Home screen will open the Print Screen see
57. ta ROBERT L NORTON Hl pynacam Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 O x a Menus only File Screens View Units Examples License User Help Preferences About Screens EE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 gt lo xj File Screens View Units Examples License User Help Preferences About DIBH SYAJ Plot Print Profile Dynamics Linkage Vibration Stress FFT Exit Status inbbls swag Sized Dynamics Linkage Vibration stress FFT Done b Compact HE DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 E 15 x c Full screen File Screens View Units Examples License User Help Preferences About O a al S AJ Plot Print Profile Dynamics Linkage Vibration Stress FFT Exit FIGURE 1 ST Home screen in each of its three sizes that may already be present on any screen from the current unit system to the selected one Five unit systems are supported ips fps SI and two mixed unit versions of SI cm kg N s and mm kg N s For the last two length units are displayed in cm or mm but lengths are converted to m before calculating any parameters that involve dynamic equations Dynamic calculations are done in pure SI for all three metric systems and in English units for the other two The Units menu also allows the independent variable for calculation to be set to one of time de
58. tes and displays the maximum normal and maximum shear stress in cam and follower at each point around the cam and also shows the dynamic force and cam radius of curvature used in the calculation Next returns you to the Home screen Fourier Transform FFT The Fourier transform of any function calculated within DYNACAM can be formed by pulling down the menu labeled FFT on the Home screen Figure 17 shows the Fourier Transform screen Any one cam segment or the entire cam can be selected for transforma tion from the upper drop down menu The middle drop down menu allows any calculated follower function to be chosen for transformation The lower drop down menu chooses the number of harmonics desired in the Fourier spectrum The RMS Sum and the Spectral Power are displayed in the right side bar Once a Fourier calculation is done the spectral information for the chosen follower function will be available for plotting printing and export from those Home screen buttons This FFT data can be used to recreate the func tions from the Fourier series harmonics as continuous functions of time in an equation solver for example LINKAGES DYNACAM allows four types of linkage follower trains to be created Fourbar linkage Sixbar linkage Fourbar slider and Sixbar slider as shown in Figure 18 There are samples of each linkage on the Examples menu Home screen and these can be used to seed your Material _ parameters Follower _ geometry External
59. testers and still do I simultane ously rewrote the code from scratch in Visual Basic The result was what is now called the Professional Edition of DYNACAM Release 9 became a mature useful and well debugged program for cam design used by over 70 companies worldwide DYNACAM 10 is a complete rewrite of release 9 from scratch and retains its feature set but has streamlined and more robust code The old program had grown like Topsy and was somewhat convoluted and a bit of a patchwork that had become difficult to maintain The new program is simpler to use with fewer screens and has much improved plotting capability Suggestions for improvements are always welcome Robert L Norton P E norton designofmachinery com
60. that if you selected a translating follower then the displace ment values are defined in length units but if you chose an oscillating follower they must be in degrees You may begin at the top or bottom of the displacement hill as you wish but be aware that for a radial cam the position values of the follower must be in a range from zero to some positive value over the whole cam In other words you cannot include any anticipated base or prime circle radius in these position data These position values represent the excursion of the so called S diagram displacement of the cam and cannot include any prime circle information which will be input later If you intend to make a barrel cam or a linear cam then the requirement that the start and end values include a zero value is no longer applicable and the values can be over any range desired As each row s segment s input data are completed the Calculate button 11 for that row will become enabled Clicking on this button will cause that segment s S V A J data to be calculated and stored After the Calculate button has been clicked for any segment s row the Plot and Print buttons for that segment will become available 12 Clicking on these buttons will bring up a plot or a printed table of data for S V A J data for that segment only More detailed plots and printouts can be obtained later from the appropriate button on the Home screen The plots and prints are ena
61. tion is shown at cam zero not at machine zero Key is at machine zero C cw cew 1 y Cam and Cam Type Se Set cam Rada roller sizing parameters eee cuter Radius Linear ee n Cam Surface inner C Outer Set Follower Motion C Translate Rotate follower Follower Type Roller C Flat parameters Folwr Arm Rotation C cw cow Zero Reterence cam C Machine Set zero Keyway is at Follower arm 2 O clock Folwr Arm CL Coords reference x E geometry Cam Start Angle on E Results ir Date dashes ex Phi ME oo omega SSB rem Min Phi AGB cee 4 Deita Theta ENA des Phi and Rho Mn Rho BEE en Cam Theta MD ses Min Rho IN len FIGURE 12 Animate cam Shift image up down The cam profile screen ROBERT L NORTON with rectangular stem and of a flat faced follower as a filled rectangle Any eccentricity shows as a shift up or down of the roller follower with respect to the X axis through the cam center The smallest circle on the cam centerline represents the camshaft and its keyway is shown as a solid red dot The larger circle is the base circle The prime circle is not drawn The default image of a radial cam shows the inner cam surface Check boxes on the left allow the inner or outer surface to be displayed Check boxes at the top select the cam surface follower path or the cutter path around the cam When the follower path is shown the pitch curve is drawn through the locus of the roller follower ce
62. y dragging the slider bar at the bottom of the screen to left or right The Mass Prop button goes to the Mass Properties screen described below Sixbar Linkage Follower Train Figure 21 shows the sixbar linkage screen The Stage 1 and Stage 2 Modes define the kinematic circuits of each stage of the linkage which can independently be either open or crossed For a definition of these terms see reference 2 The Angle from Line of Link 2 to Roller Arm parameter defines the included angle between the kinematic link 2 and the arm radius to the roller The link lengths are always defined as the pin to pin distances of each link Link numbering is standardized with link 1 always the ground link link 2 the link directly driven by the cam and pivoted to ground link 3 a floating coupler or con Choose circuit gl DYNACAM Plus by R L Norton Copyright 2009 Release 10 Rev 1 6 7 12 23 09 Linkage Screen Help Calculate Redraw Zoom Out Normal Zoom Ir Step Run Mass Prop Copy Print lt Back Next gt Autocale p Select Linkage Type FourSide Mode Apply SVAN Cam Angle Fon Fourser C Siar Fourside C Sixside open C Crossed Com arm C EndEttector E ces Please provide the relevant parameter values for your linkage z z B Linkage Parameter EE Y Slider axis Angle trom Line of Link 2 ta Roller Arm A Link lengths li 2 1 3 Length of Link 3

DYNACAM 10 USER MANUAL - Norton Associates Engineering

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