Home

yansong guo design and implementation of a service

1. In manual mode all the parameter must be defined correct otherwise the system will deny the request and send the feedback to the control panel For example if the pallet ID is not well defined the system will reject the request and send back a message like Pallet Not Exist The whole manual mode is processed in S1000 without the help of PLC The S1000 will receive the message through web service and it will process the command compare with the data which it stored If the command is correct the S1000 will modify the 63 memory and store the new data in it Otherwise it will reject it and wait for the new op eration 4 6 3 Consultation mode The consultation mode here means that the user can consult the status about buffer and the pallet The consultation operation has been divided into two actions PalletInfo and GetState DrawServiceCell Pa ee SetPalletinfo Input PalletInfoReq PA PalletID string quipmentChangeState evt ding wan Figure 57 Control panel for PalletInfo action Figure 57 shows the control panel for PalletInfo action PalletInfo is used for getting the pallet information The user needs to give the S1000 pallet ID as the input If the input pallet is stored in buffer S1000 will send a feedback message back to user with the position of pallet Otherwise S1000 will send the feedback message as the pallet is not inside the buffer DrawServiceCell Action GetSt
2. 42 Homing 4 Measure Motor Data Motor Type EMMS AS xS Y a Controller Bs ed A Control Interfac Motor Size 70 5 18 M Brake Za HE Digital 1 O Gearbox None e y AA HE Analogue l _ a n A PHI Jog Mode 7 E x gt E Position Set Tal Axis Type DGE ZR Toothed belt axis zi kz Closed Loop Axis Size 25 y EX Error Managem Working Stroke 600 mm 3 Ex Trace Configuri eee EX Trace Data Type Of Limit Switch NC Normally Closed zi 8 oO CMMS AS xaxe External Gearbox IV Present 1 1 5 Configuration im Application Data B P Axis 0 Homing 4 Measure Motor Controller B A Control Interfac 4 Hi r Output Figure 41 graphical interface of FCT As we can see in the figure all the EMMS AS motor types can be selected in the FCT as well as the axis types The other parameters such as motor size axis size and gear box can also be defined in the FCT which makes the descriptions of the system highly precisely Therefore the control of the motor can be very accurate Every time before the motor starts working a homing process must be executed to make sure the control ler find the reference point for the further active There are several ways to perform the homing process limit switch block actual position limit switch with zero pulse block with zero pulse and zero pulse Each of them has a unique pattern to detect the home point In this thesis the limit switch has been chosen as the ho
3. There is a slider that carried a fork at the bottom of the pneumatic axis With the help of the pneumatic system the fork can move along the pneumatic axis The load unload 38 process is based on this movement The design method of the fork and pallet can be seen in Figure 32 Figure 32 the fork and pallet design method The process of carry release pallet from the fork is based on the vertical movement of the end effector which can be done with the help of Z axis module When the pallet is carried by the fork on the way to destination a screw will fix the pallet on the fork without any movement that caused by the inertia Detection of the position of the fork can be done by two FESTO SME series proximity sensors which mounted on the two end of the pneumatic axis By using these two sen sors the PLC can be aware the position of the fork so it can execute precisely Figure 33 the proximity sensor on the end effector module 39 4 CONTROL SYSTEM The mechanical components can help the system build the foundation to accomplish the tasks but without the aim of the controlling system the mechanical components are more like the body without the soul The controlling system used here is comprised of a programmable logic controller which specified as Modicon M340 an INICO S1000 controller working as a communication interface and the information memory two ser vo motors five valves and eleven sensors The communication of the int
4. is called loosely coupled There are two advantages of loosely coupled services one is the flexibility and another is when the structure and the realization of service are changing the system can still exist It has been over twenty years since the SOA principle has been proposed There are also some prototypes SOA systems such as Common Object Request Broker Architecture COBRA 10 However nowadays there is an easier and more widespread approach Web service The web service becomes a main work pattern for next generation Internet applications 11 According to the definition of World Wide Web Consortium W3C the web service is a software system designed to support interoperable machine to machine interaction over a network 12 In another word web service is a set of standards to define how the applications can interoperate through the web SOA is focusing on the sequence of op erational activities or business process 13 The user can use any languages and any platforms they want to program the web services as long as clients can query and access these services based on the web service standard Web service needs a set of standards to realize the creation of distributed applications There are a lot of data representation methods and system types to achieve the interoperation web service must supply a set of standards which can be used between different platforms different programming languages and different system models The basic
5. 0800 p P P BMX CPS 2000 E 0 BmxP342020 SerialPort 8 Ethernet 1 BMX DDI 1602 3 BMX DDI 1602 4 BMX DDO 1602 E Modicon M340 local drop Function Analog ETH TEPIP y Communication gt Counti Task Discrete masT Motion Net Link sa 51000 y Figure 49 Set up of the Modbus TCP port In the function above the port type can be defined in Function block while the Net Link block can choose the net which needs to be used In our case the net link should be S1000 To send and receive the messages through the Modbus TCP the IP address must be defined at first It is work as an address label over the Internet communication In the S1000 net link the IP address can be easily defined 52 After the communication address has been set up the message transfer functions must be defined in the programs In Unity Pro software there are two special designed func tions that used for transmitting the Modbus TCP messages The READ_VAR and WRITE_VAR The READ_VAR function is used for receiving the Modbus message which sent from the other devices In ST language it can be represented as e READ_VAR Address Object_Type First_Object Object_Number Manage ment_Param Receiving _Array In the READ_VAR function there are several different parameters that need to be well defined otherwise the communication may occur some errors Since the READ_VAR function can be used in the
6. Elsevier Inc 2010 A D Brahim Rekiek Assembly Line Design The Balancing of Mixed Model Hybrid Assembly Lines with Genetic Algorithms 2006 L Wang FACTORY AUTOMATION SYSTEMS EVOLUTION AND TRENDS Singapore e O sagir Design and Implementation of a Random Access Buffer for Mixed Production Tampere 2009 Service oriented architecture Access on September 27 2012 Available http en wikipedia org wiki Service oriented_architecture W eb service_protocols Enhancing Efficiency of Automobile Assembly Line Using the Fuzzy logical and Multi objective Genetic Algorithm tekij Adham A A J Brisbane 2012 M Zhou MODELING BUFFERS IN AUTOMATED MANUFACTURING SYSTEMS USING PETRI NETS tekij Proceedings of Rensselaer s Second International Conference 1990 K Shin Scheduling job operations in an automatic assembly line tekij Robotics and Automation 1990 Proceedings 1990 S Baral Probabilistic modeling of the states of a buffer in a production flow system Engineering Management osa vuosik 40 nro 4 pp 381 389 1993 Y Zhao Enterprise Service Oriented Architecture ESOA Adoption Reference tekij Services Computing 2006 SCC 06 2006 X Lu An investigation on service oriented architecture for constructing distributed Web GIS application tekij Services Computing 2005 Web service Access on October 27 2012 Available http en wikipedia org wi
7. Technology The factory line is an embedded service oriented distributed production line Each of the cells is embedded a controller responsible for controlling the cell The messages of cells will be sent to a centre controller through the web service Figure 2 Overview of Fastory line 12 This production line is a pallet based automatic line which contains eleven cells Ten of them are assembly cells and one is for loading and unloading process There is a con veyor in the middle of the system Figure 2 shows the top view of the factory line As can be seen in the figure the whole line is a close loop It starts at the loading unloading cell the left end cell and the robot in this cell will load or unload the product onto pallet Then the pallet will carry the as sembly parts and move through the rest of the cells clockwise in sequence on the con veyor After the pallet finished the process it will return to the load unload cell to un load the finish product and wait for the new product In each assembling cell there is a SCARA robot which can perform the manufacture operation In front of the assembling cells there always conveyors with two paths when the product needs to be assembled it will be transferred onto cell s main conveyor otherwise it will be sent to cell s bypass conveyor to move to the next cell To identify the pallet a RFID device is placed at the entrance of every cell with a stop per The controller will decide
8. also be sent to the upper web service A Modicon M340 PLC is chosen to control the real executing of the buffer With the help of two servo controller PLC can realize the buffer functions accurately 5 1 Future work The buffer now can be treated as a finished system However there are still some other work can be done in future First of all an energy detecting system can be integrated into the buffer An energy analysing system is an independent working unit which can ana lyse the energy consumption of the buffer in real time It can be installed in the control cabinet It can calculate the energy consumption by the voltage cost of the buffer There are these systems in the other cells in Fastory line and it is working well As part of the production line the buffer should also install this system in future Secondly a pallet detecting component may need to be attached on in front of the grip per In the recent system the decision making system in S1000 is only based on the S1000 memory However the buffer may not acknowledge if the data in memory is not correct This may cause some collision and machine damages of buffer To fix this problem a pallet detecting sensor can be instaed in front of the gripper so every time the gripper want to load a pallet onto the rack it will sense if there is a pallet already or not 10 11 12 13 14 15 67 REFERENCES Y Qin Micromanufacturing Engineering and Technology
9. also have enough spaces between different shelves to make sure the Z axis motor can execute the vertical movement Figure 22 CAD view of shelf 3 4 The operating robot The main structure of the buffer is a 4 axis robot that used for completing the function ality of the buffer The robot can grab the pallet from the conveyor and carry it to the warehouse as well as retrieve the pallet back to the conveyor from the warehouse Since the warehouse is a three level frame the robot must has the capability of moving along X and Z axis Besides to make sure the robot can reach both side of the warehouse a rotary component must be installed on the base of the robot Figure 23 separates the robot into different modules with the different colour X axis module Z axis module rotary module and the end effector module 31 Figure 23 CAD view of the robot The linear movements along the X axis and Z axis are achieved by two AC servo motor since they can provide a high precision and repeatability operation The reason for choosing the AC servo motor is because of the servo motor contains the encoder which supports the accuracy movement A pneumatic rotary drive is used for rotating the Z axis within 180 range Another pneumatic end effector is responsible for driving a fork shaped gripper that used for grabbing the pallet from the conveyor and pallet 3 4 1 X axis module X axis module is mounted on the Festo MUC 25 frames which also hold by
10. code and operation value Figure 13 shows an example of IL language under Unity Pro environment When the in put variable A and input variable B are true the output Q will be executed LDA AND B sr Q Figure 13 Example of IL programming Sequential function chart SFC is the language that used fir fulfilling the ssequential logic control The se quential workflow is separated into different steps and transition conditions dur ing the programming process Each step presents a control mission and ex pressed by the block Structure text Structure text is a PLC language that using the structured word to describe the program which likes a high level language In the huge PLC systems ST is al ways used for describing the relationships between the variables in the control systems ST can program the functions that the other languages can not achieve The ST language asking the engineer has some basic knowledge of the high level program languages Figure 14 shows the instance of the ST language When the PalletExist is true Xrecord0 and XPosition will be set as true while Stopper will be set as false Otherwise the output value will be reversed 25 IF PalletExist THEN XRecordO true Stopper false XPosition true ELSE Stopper true XPosition false XRecordO false TEST 0 END IF Figure 14 Example of the ST language The ST language is easy to arrange the sequential
11. defined as the PT The brief explain of the executing theory of TON function is when the input StartDelay is triggered the function will wait for a period as the PresetDelayTime defined Then the output will be turned to be true If the input is turned off the output will also be turned off no matter it has been turned to be true already or not RS_Instance S Set R1 Reset Q1 gt Output ja Input for set the output Input for reset the The output variable output Figure 46 RS function in Unity Pro Figure 46 shows the structure of RS function in Unity Pro The input S will turn on the output while the input R1 will turn off the output For the RS function the reset is in the domain position It means when the R1 is true no matter what value the S is the output will be reset The TP TON and RS function built the foundation of the sequen tial control of the motor 4 5 System communication method The whole storage buffer system is composed of three levels servo level PLC level and the S1000 level For connecting them together there are different method and interfaces that need to be used Figure 47 shows the sketch of the system communication methods 49 gt Modbus TCP ARAS ode A 4 il en e el e Usb connection I O interface Serial port i y Figure 47 System communication layout The servo controllers are the lowest level controller which communicat
12. different Modbus serial protocols the parameters may con tains the different variables When the READ_VAR using for the Modbus TCP messag es the Address should be the IP address of the target device Object type is the vari able types First_Object presents the first object which should be read Ob ject_Number is the quantity of the variables need to be read and Management_Param which contains the management parameters By using this READ_VAR functions the data can be saved in the specific memory addresses which starts at First_Object The program can call and modify those variables according to the memory addresses The WRITE_VAR function is used for sending the Modbus message to S1000 It can be programmed in ST language as e WRITE_VAR Address Object_Type First_Object Object_Number Da ta_to_Write Management_Param The same as the READ_VAR function there are several parameters needs to be pre defined before the messages can be successfully transferred When the WRITE_VAR is used for transmitting the Modbus TCP messages the Address is presented as IP ad dress Object_Type means the type of variables First_Object is the address that need to be send to S1000 Object_number is the number of variables that will be send to 1000 Data_to_Write is the table containing the value of the objects to be written and Management_Param that includes the management parameters
13. motion of the producing process so in this thesis the ST language is used for being the programming language of the PLC 26 3 MECHANICAL LAYOUT IMPLEMENTATI ON The buffer is going to be implemented into a mixed product automatic production line which is totally automated except the process that loading the pallet onto the line Since there is no temporary storage space in this system the station starving or blocking may stop the producing which restrict the capability of the whole system To solve this prob lem a temporary storage buffer can be integrated into this system to provide an extra store place and support the system which can reduce the bottleneck of the system Be sides by using the storage buffer the system can get more flexibility to arrange the pro ducing scenario The mechanical layout of the buffer cell has been explained in this section The mechanical layout design is based on the previous work In this thesis part of the buffer has been redefined according to the new orders of the system 3 1 Overview of the buffer The buffer needs to be implemented into the factory line that based on the conveyor system It contains a cell that carries the entire system a conveyor that connecting the buffer to the rest of the system a frame construction that holds the robot and warehouse a special purpose robot which used for transferring the pallet between the warehouse and conveyor and a three level warehouse that used f
14. short lifetime rapid renewing dynamic fast changing poor stability and unpredictable market With the unbelievable fast evolution of modern information and internet tech nology such as Object Oriented Software Engineering Virtual Instruments Based Ar chitecture Distributed and Embedded Real Time Systems and service oriented architec ture 3 make the manufacturing industry fulfil the requirements of modern market be comes possible The highly automatic production lines full of robotics sensors actua tors and computers are used more and more instead of the humans in the modern facto ries Automatic manufacturing line is developed based on the assembly lines It can work automatically in accordance with the prescribed It requires the on line devices can not only automatically complete the scheduled procedure and process to make the raw ma terial become to qualified products but also locating and clamping transferring sort ing and even packaging can be done automatically This type of integrated mechanical and electrical device system which can work automatically is called automatic manufac turing line In order to achieve automatic producing automatic manufacturing line inte grate applied the mechanical technology control technology sensor technology drive technology and network technology by using some auxiliary devices to combine the different machining devices together with control of the hydraulic pneumatic system and elec
15. the plate of cell with the same kit The purpose of X axis module is to supply the linear accuracy movement along the X axis It is responsible for carrying the pallet to the certain col umn racks As we can see in Figure 24 the red part is the X axis module it comprises an AC servo motor two axes located on the top and bottom separately and a connecting shaft that used for transmitting the power from the up axe to the bottom one 32 Figure 24 View of X axis module The components are got from FESTO Company since they can provide the overall solu tion of the system For choose the correct components FESTO has a certain tool called Positioning Drives which is used for determining the suitable axis slider types and servo motor To use this tool the requirements of the system can be seen in Table 2 Table 2 System requirements of X axis system 24 Assembly position Horizontal Maximum moving mass 21 5kg Usable length 700mm Necessary repetition accuracy 0 1mm Axis type Gantry axis Assembly position Up or down Mass position 300mm offset in X direction According to the table above by using the FESTO tool the system components have been selected Table 3 Components of the X axis system Axis DGE ZR 25 Guide Ball Bearing Motor EMMS AS 55 TS AC Servo Controller CMMS AS C4 3A 33 There are three sensors in the X axis system Two indust
16. time e Final speed e Wait for current positioning reject or ignore initial instruction 30 46 Workspace a Prok EMI c ms as zaxe Configuration 2 Application Data nn Profile Comman Dest Input Comment Eg Axis i 12 Homing 1 la 50 00 0 END 4 Measure 2 jA 150 00 0 END Motor Data 3 A 130 00 0 END 6 Controller 4 A 240 00 0 END E 4E Control Interfac 5 lA 220 00 0 END HE Digital VO 6 a 340 00 O END F ES E Analogue Y 7 Ta 220 00 O END PB Jog Mode A Position Set Tal EN kz Closed Loop 9 A Error Managem 10 A Ex Trace Configuri 1 jA EX Trace Data X 12 A m J gt 1 lA p Device Status Movement Data Test Cycle Enable Operation Mo Increment 1 00 mm Delay Time 0 00 s O Stop Device State Velocity 99 8 mm s E Manual Control O MC Single Step Error Jog O Warning Actual Position 0 00 mm Device Control o Figure 42 Interface of manual moving mode 4 4 2 Servo motor control method The servo controller is controlled by the PLC through the I O interface The PLC can set the working mode of the servo controller by changing two bits data Table 6 shows the functions of each mode In this thesis the normal positioning mode O has been chosen as the working mode Table 6 Control mode of servo motor Mode Function Control bit Mode 0 Positioning 00 Mode 1 Jog function 01 Mode 2
17. which path to send the pallet On the cell main conveyor there are another two stoppers one of them is used for stopping the pallet at the assem bling point and the other one is used as a safety locker to make sure the assembly pro cess will not be interrupted At the end of bypass conveyor there is a stopper that used as a traffic controller to make sure the pallet flow will move smoothly without any colli sion n A A eee ee eee eee eee iS SS SS ee eee a aoe a a 0 0 ee o eee o eee FAST Lab Figure 3 Top view of fastory line 13 1 2 Problem Statement With the help of the service oriented architecture the assembly line that described in previous section can work fluently However no matter how reliable the system can be designed there is still no system can guarantee the trouble free manufacture To solve this problem a storage buffer should be used Since the buffer is integrated into a manufacturing system it must have the ability to communicate with the centre controller of the line The buffer can load the pallet from the conveyor to buffer racks and retrieve the pallet from buffer to the conveyor The store position can be chosen randomly or based on the specific order Also the retrieve command can be position domain or palletID domain To achieve those functions there are several problem need to be solved e How to establish the communication link bet
18. who made something must finish them The cottage industries were leading a revolution of manufacturing The factories ap peared during that time Lots of land less peasants went into factories and working for the entrepreneurs This can be seen as the start of modern industry With the economic and technological developments the mass product became possible at the end of the nineteenth century Numerous standardized goods were produced with the help of assembly line Manufacturers needed to find a way to react quickly to market trends or lose market shares 10 Recent days with the rapid technology development the manufacturing becomes more and more automatically The computer is aiding the modern manufacturing getting into a new generation Nowadays the manufacturing is facing an indeterminate rapidly changing and increas ing competitive international market The customer is driving the market and the market is leading the manufacturing companies To satisfy the customer need the manufactur ing industry is changing from product oriented to market oriented from company lead to customer lead The demands for the manufacturing product by the customer are multi species batch changeable high capability high quality high reliability short delivering time reason able price consummate marketing and after sales service which will also change with the customer status According to this situation the manufacturing product is facing a
19. will not be erased by the loss of power The only way to change the retained variable is using a certain program sentence SAVE_RETAIN But the retained variables are saved in the flash memory which has a maximum erase write life time of 100000 cycles Over this number the 1000 may be burned So the retained variable should be used as less as possible NICO ST Logic Build VARIABLES Global variables Edit Retained variables Edit ST PROGRAMS loadingpro Edit Remove testst Edit Remove calibrating Edit Remove unloadingpro Edit Remove changestate Edt Remove state Edit Remove palletinfo Edit Remove setpalletinfo Edit Remove Add new Figure 38 S1000 variable configure page 4 3 Servo motor The servo motor is a rotary actuator who allows for precise control of angular position 28 which widely used in the industrial producing Usually the servo motor comprised a motor which coupled to a position feedback sensor Besides a special designed con troller is always required by the motor The servo motor is always compared with the step motor which also has the good per formance in position control A step motor drive signal can specify the number of steps of the movement to rotate so that the step motor can control its movement speed and distance Since the step motor does not have the encoder so it cannot get the feedback signal of the real performance this makes the step motor becomes an open loop position control which limit
20. 3 3 Warehouse The warehouse that used in the buffer is two three level shelves and for each level there are three storage racks The CAD drawing of warehouse is shown in Figure 19 29 Figure 19 CAD drawing of warehouse The purpose of this warehouse is to store the pallet which carried the mixed products This makes the racks must fit the size of the pallet Besides the pallet loading unloading process is also need to be taken into the consideration For the purpose of efficient use of space and decrease the energy consumption the warehouse has been designed as a three level two parts frame that surround a special designed robot Figure 20 shows the view of the pallet Figure 20 View of pallet There is a groove on each side face of the pallet that used as the track of the fork The fork can carry the pallet to top of the racks then after a vertical movement the pallet will be put on the surface of the racks For the need of positioning the pallet on the rack the tilt pillars have been set to keep the pallet when the fork going back To increase the accuracy of the positioning the chamfer has also been used on the pallet 30 Figure 21 CAD view of the rack The racks are assembled on the shelves and each shelf can contain three racks There are six shelves so the warehouse can supply eighteen store positions in total There are some empty spaces between the racks since the pallet is bigger than the racks and there should
21. 32 Table 4 The parameter values that used in Positioning drives 0 34 Table 5 Components of the Z axis SySteM oooooooooocccccnnonooooocnonococononannncnnnnnnccnonanons 34 Table 6 Control mode of servo motort ooocccnnnnocccnnnnnoccnnnnonocononanocononanocononanicnicinnn 46 1 INTRODUCTION Manufacturing is to make products that have been designed for certain applications It is a general term referring to industry However manufacturing has the different meanings during the human history 1 Knowing how to make tools is the main characteristic that distinguish human from the animals Figure 3 shows the different periods of the manufacturing Computers in e anufactu ri S g proc uction ele working and the new cottage Mass industries First factories oras gt gt industries pCarpenters and 3 smiths SS a Ss ss m Past 10000 years 1000 years 100 years 10 years Now Future ago ago ago ago Figure 1 History of Manufacturing 2 The first stage is first metals which is back to 10000 years ago Back to that time our ancestor started to use some simple tools for hunting The tool may be just some stones or pointy woods During that age the manufacturing just means some hand tools Then the time is moving to the Carpenters and smiths During those years the manu facturing is mainly focusing in some specialised areas such as carpenters and smiths The people
22. By using the WRITE_VAR function the messages that contain the variables can be sent to the regis ters which located in 1000 The variables can be defined by directly valuing the ad dresses On the S1000 side the same as the PLC part the communication link should be set up before the data transmission There are several different I Os can be defined in the 1000 configuration page such as wireless I O and Modbus I O In our case the Mod bus TCP Scanner should be chosen The IP address of the Modbus TCP server can be stored in the configuration page as well as some other related parameters The Modbus TCP server here is Modicon PLC so the IP address should be 192 168 7 10 Also the IP address can be set in the Network page To successfully exchange the data the IP address of S1000 and PLC should have the same first three bytes so the IP address for 53 S1000 is 192 168 7 9 After the server well defined the register for store the Modbus TCP variables need to be created It can be created in the I O configuration page also There are two new I O need to be defined one is for input data and another one is for output data Inside the configure page there several parameters should be assigned Register type Modbus scanner slave address register block start address and the regis ter quantity A very important here is that the register block start address should match the First_Object that defined in PLC program Otherw
23. NGTELENCOS ada 67 ABBREVIATIONS SOA W3C COBRA SOAP DCOM WSDL SCADA LD FBD ST IL SFC FCT Service oriented Architecture World Wide Web Consortium Common Object Request Broker Architecture Simple Object Access Protocol Distributed Component Object Model Web Service Description Language Supervisory Control and Data Acquisition Ladder Function Block Diagram Structure Text Instruction List Sequential Function Chart Festo Configuration Tool LIST OF FIGURES Figure 1 History of Manufacturing 2 secs dscensotsactdsodiedgocsaadsondavansodaastdsendieaageasauadscndaeass 9 Figure 2 Overview of fastory line is sssisiocsnrasnassdtasalacendsisdeasceancasuansdea alacant iasdeanasdaatals 11 Figure 3 Top view of fastory Meca ii 12 Figure 4 Basic assembly lMeDaccisiconcoinidonicanisvacidnidonicunddaccdnddonicanisonccdnidonicundiinccidiiaaias 14 Figure 5 Two stage DIE aa 15 Figure 6 Architecture Of web service sasssccsitetsanssdeseasdentsaceadendecaadetsanesdebaacsdeetsaceadeneeass 17 Figure 7 SOAP connection A este tir a ia Meu dt 18 Figure 8 SOAP Envelope renren an eta E aa Ea ARRE 18 Figure 9 Compare of WSDL1 1 and WSDL2 0 12 ooooonnonnonnononanonanonononnnnnnnnnnnnnnnononnns 19 Figure LO Structure OF PLO cispintnirasa aiaa a E a Eea aa E Seaia 21 Figure 11 Example of Ladder Didgramicion adan iii 23 Figure 12 Example of EBD cito na a a a a a a 23 Figure 13 Example of IL programming AAA AAA A IA GA Ri 24 Figure 14 Example of the
24. ST language icsecsccesdaiedecsicisstessaisnetsdacsedetdadad esidbsscetsalucetsdaias 25 Figure 15 Overview of the buffer A A A E A A A 27 Figure 16 CAD drawing of Cell scicsescosscsivcsstseetsoascadvcseucsessoancedecsicestsoascedesceaseetseanceavee 27 Figure 17 Safety A sods nnii ainiaan is 28 Figure 18 control cabinet and pneumatic valve ooooononococccononanananononn nono nono nn nono nono nono nnnnos 28 Figure 19 CAD drawing Of warehouse cooooooooccococooooooooononn nono nono non nono nono nono nono nro nono nono nnnnos 29 Figure 20 View of pallelaniin danita dsd a 29 Figure 21 CAD view A iaa 30 Figure 22 CAD View Of SHELF it A A A it aa ai 30 Figure 23 CAD view of the TODO AA A A A A 31 Figure 24 View of X axis MOQU E a ssiscsisccivessssieecdacstocsassteesdsscavesuassdeecdacctoesasdyssaaccavees 32 Figure 25 View of proximity Sensors scssciiscshcansiusnsoedavensoaadensodeaeedcaaaauanouawansoaadasssocuaks 33 Figure 26 Zaxis m dulos enia EEE E EEA E Eaa EA EAE Ei N 34 Figure 27 3D view of the motor assembly module oonnnnonccnnonnnoanananon nono nono ono nn nro nnnnnos 35 Figure 28 View of the proximity Sensor ansiada iia ai da E 35 Figure 29 3D view of rotary module 11ssssssssssssessssssssssssssssssssssssssssssssssesssesssesssesees 36 Figure 30 DRQD rotary driver 18 sacssssinsensessnnsrscedaesnsesadeacscaassasosasasascaaaesnsesadacascadans 36 Figure 31 3D view of end effector Module siscesiicssssstestetassestecsedecZacntaestaccsdeadscasbeatectad
25. TAMPEREEN TEKNILLINEN YLIOPISTO TAMPERE UNIVERSITY OF TECHNOLOGY YANSONG GUO DESIGN AND IMPLEMENTATION OF A SERVICE ORIENTED AUTOMATION FOR A STORAGE BUFFER Master s thesis Examiner Professor Jos Luis Martinez Lastra Examiner and topic approved by the Faculty Council of the Faculty of Automation Mechanical and Materials Engineering on 7th November 2012 ABSTRACT TAMPERE UNIVERSITY OF TECHNOLOGY Degree Programme in Machine Automation Guo Yansong Design and implementation of a service oriented automation for a storage buffer Master of Science Thesis 68 pages November 2012 Major subject Factory Automation Examiner Professor Jos Luis Martinez Lastra Keywords Storage buffer service oriented servo motor PLC manufacturing production line WSDL Nowadays the efficiency of the industrial manufacturing has been increased dra matically thanks to the development of automation technologies However with increasingly fierce competition in the international market manufacturing systems are required to be more flexible and to be able to react rapidly to the changes of customer demanding In this background the service oriented production line is of great potential in improving flexibility configurability and productivity of the industri al manufacturing The storage buffer which serves as a temporary pallet storage for the automatic production line in FAST lab is designed and implemented based on the service orie
26. Travel program 10 Mode 3 Synchronization 11 The I O interface has been shown in Figure 43 47 24V DC Sot Controller release DIN 5 PE End stage enable DIN 4 l A STOP DIN 13 4 wet Record selection O DINO AH Record selection 1 DIN 1 4 Record selection 2 DIN 2 4 e Record selection 3 DIN 3 4 ee Record selection 4 DIN 10 A Record selection 5 DIN 11 4 Les Mode DIN 9 AE Mode DIN 12 4 _ Start for the positioning process DIN 8 4 at Limit switch O DIN 6 E Limit switch 1 DIN 7 Q Ready for operation DOUT O 4 Q Default Motion Complete DOUT 1 4 Q Default Ack Start DOUT 2 des Q Default Error DOUT 3 Figure 43 The I O interface between PLC and servo controller To active the motor controller release and end stage enable should be turned on while stop should be turned off After this process the motor is powered on But if the user want to run the motor the limit switch 0 and limit switch 1 should also posi tive otherwise the motor will not move for the safety protection The homing process can be triggered by turning on Start for the positioning process in the meantime keep all the record selection bits to be negative During the positioning process both the Start for the positioning process and record selection bits should be turned on to inform the destination to the ser
27. aded into S1000 through the S1000 configure web browser The detail of the different operations will be explained in the system operation section After the WSDL file has been updated the web service function needs to be set in the S1000 The Web service can be created in the Web Service sub clause with the specif 1c configuration of the contents In the S1000 there are three different operations can be defined EVENTS INPUT MESSAGES and OUTPUT MESSAGES In this case the EVENTS and INPUT MESSAGES has been used for achieving the tasks The EVENTS function used in S1000 is for sending the web messages initiatively It can launch the message transmission by itself without any request and do not need any response There is only one event which is responsible for the EquipmentChangeState operation in this thesis The events that intended to be used in the S1000 must be de fined in the Web Service sub clause with an ALIAS and the ACTION which corre spond with the WSDL file In the meantime the ACTION also needs to be edited All the variables which defined in the WSDL relevant operation must be contained inside with the same names 55 After the events have been created in the Web Service the programs must have the capability to trigger the events which means the certain sentences must be written into the program To call the EVENTS functions the sentence WS_Publish need to be added into the pro
28. al functions To establish the link to the web service a proper WSDL file is necessary In this thesis the WSDL file contains seven different operations with the certain functionalities They are e CalibrateBuffer reset the buffer when the buffer first time power on or error oc curred 54 e Load loading process for transfer the Pallet from conveyor to the racks e Unload unloading process for transfer the Pallet from racks to the conveyor e EquipmentChangeState the feedback information for equipment status e GetState request the buffer initiatively e PalletInfo request the information about Pallet position and PalletID e SetPalletInfo set the pallet information manually RobotPortType 4 CalibrateBuffer Dl input P Request Calibrate lt l output P Response e LoadingRsp gt Request e LoadingMsg Ql output P Response LoadingRsp UnLoad input Request LoadingMsg P Response LoadingRsp EquipmentChangeState Ql output P EquipmentChangeState EquipmentChangeState HE GetState Dl input P Request GetState lt A output Response E State l input P Request PalletID Ql output SetPalletinfo P Response PalletinfoRsp Request E SetPalletinfo P Response e SetPalletinfoRsp Figure 51 S1000 WSDL file Figure 51 shows the WSDL file used in S1000 The WSDL file should be uplo
29. ate SetPalletinfo Input GetState UnLoading k GetState stri EquipmentChangeState evt cina PalletInfo lLoadi Calbratetufer Figure 58 Control panel for GetState action 64 Figure 58 is the control panel for GetState operation GetState action is used for get ting the buffer status To trigger this action user only needs to set the parameter GetState as 1 and invoke it The S1000 receives the request and checking its memory to find out the status of buffer then sends it back to user through web service As the Manualoperating since this consultation mode is just the matter of information it will only run in S1000 with no affect to PLC and servo controller 4 6 4 Feedback mode In the Fastory production line the web service needs to perceive the real time condition of the buffer to arrange the producing tasks A feedback mode is used for transferring the current buffer status to the web service without the request To achieve the compati ble characteristic the message is using the IPC 2541 states based on EquitmentChang eState events There are seven events included in EquitmentChangeState schema In our case since the buffer does not have that much status only five of them in used The screenshot for the IPC 2541 events used in WSDL file can be seen in Figure 59 ent name Calibrate type xs string gt t name EquipmentChangeState gt e gt name dateT
30. components of the web service are SOAP WSDL and UDDI The whole interoperability is based on them The following sections will describe their principle 2 3 1 Web Service Structure In general web service contains three differences service provider service broker and service requester Figure 6 shows the architecture of the web service 17 Figure 6 Architecture of web service 14 There are three operations defined in the web service model find publish and bind Service requester can implement the operations of finding and binding The service re quester requests the service broker searches for the available specific service provider which provides the certain service Once there is a provider meets the conditions the service requester will bind with the provider and start to invoke the service The service broker is more like a storage and distributer It stores the service provider s description information and when there is a service request it will search for a match provider for the requester The service provider is actually the service owner which provides the ser vice for the service requester The work process for the web service can be described as followed The service re quester wants to obtain the certain service It will send this request to the service broker once the service broker receive it it will find a match service provider in its data base and send the feedback to the requester After the service request
31. ction http www tut fifast robot RobotPort Type UnloadingRespc Edit body Save Loading ST Program LoadingPro Remove Reg action http www tut fifast robot RobotPort Type DrawRequest Edit body Response action http www tut fifast robot RobotPortType DrawResponse Edit body Save CalibrationPro ST Program Calibrating Remove Request action http www tut fifast robot RobotPort Type CalibrateBufferR Edit body Response action http www tut fifast robot RobotPort Type CalibrateBufferR Edit body Save BufferState State Remove http www tut fifast robot RobotPort Type Get State Edit body on http www tut fifast robot RobotPort Type BufferState Edit body Save PalletinfoRsp ST Program Palletinfo Remove equest action http www tut fifast robot RobotPort Type PalletinfoReq Edit body Response action http www tut fifast robot RobotPort Type PalletinfoRsp Edit body Save SetPos ST Program setpalletinfo Remove Request action http www tut fifast robot RobotPort Type SetPalletinfoRec Edit body Response action http www tut fifast robot RobotPort Type SetPalletinfoRsp Edit body Save Figure 52 Web Service edit page 4 6 Buffer operations In the buffer system there are four kinds of operations Loading operation unloading operation manual operation and consultation operation For each operation there are a set of programs that used for supporting the request manipulation The logic for execut ing the operations is d
32. der is optional but if it is provided it has to be the first sub element in the envelope The SOAP body is mandatory which contains the actual SOAP message which intended to send to the ultimate endpoint The SOAP body is constituted by the body blocks The body blocks could be application data RPC method and parameters or SOAP fault 2 3 3 WSDL The Web Services Description Language WSDL is an XML based language that is used for describing the functionality offered by a Web service 17 It is a machine readable description about how to call the service and what data structure it returns Currently the WSDL1 1 is instead by WSDL 2 0 The WSDL 2 0 has been endorsed by the W3C It accepts binding to all the HTTP request methods 18 The main difference between WSDL1 1 and WSDL2 0 is their terminology Figure 9 is the comparison of the WSDL 1 1 and WSDL 2 0 WSDL 1 1 WSDL 2 0 definitions description Abstract Section H i i DE H H i i O O operation output Concrete Section i i Figure 9 Compare of WSDL1 1 and WSDL2 0 16 There are seven objects in the WSDL files They are e Service Contains the collection of ports e PortType Abstract interface definition of web service e Message Contains the function parameters separated input and output or de scription of document e Types Contains the data types that used in the web service e Binding Specifies the SOAP binding style and the transport p
33. eads 37 Figure 32 The fork and pallet design Method oooinnnnnnnnnnnnnnonononnanananono nono nn nn nn nn nn n nn nn nnnnos 38 Figure 33 The proximity sensor on the end effector mOdulO ooonnnnnnnnnnnicnnncanaoaaoannnn nono 38 Figure 34 Overview of control A a anda 39 Fig re SO Modicon MIAO Li A ASIA A A it aio 40 Figure 36 BMXP342020 left and 1602 DDI O right module ooooonnnninnnnnnnninccnnnnineccnos 40 Figure 37 S1000 with wireless antenna mecciuniivaciuai ndidanidvancanidnaionnidnnncdiionicani nnccaid nad s 41 Figure 38 S1000 variable configure page oooooccocnccccccononoonn cnn non nono nono nono nn ono n nro nn nn nn nn nnnnos 42 Figure 39 Z axis motor left and X axis motor tight ooonnnnnnnnnnnnnnnnonnoaoononnnono non nono nnnnnos 43 Figure 40 Servo controller with COMMUNICATION interface ooo 43 Figure 41 Human machine interface Of FCT uuiiniinccccccacacanananann nono non nono nono nn nn nn nn nro nnnnos 44 Figure 42 Interface of manual MOVING mode oooooononnnccnnccononanannn nono nononon ono nn nro nn nn nn nnnnnnos 46 Figure 43 The I O interface between PLC and servo controller oooonininicinacannacannn ono 47 Figure 44 Pulse function in Unity PO ici 47 Figure 45 Delay function in Unity Pro osivicouniondoduncindoiunioidaduncdodenundindeduncdodenaniidodun inueda 48 Figure 46 RS function in Unity Pro NAAA IA aan AAA RIA A 48 Figure 47 System communication layout ooonnnoncccccooconoooooaonn nono nono non nono nro nn nono nn nn
34. ed the accuracy of the motor All the controls of the step motor are based on the counting of steps therefore if steps are miss may cause the errors This lack can limit the capacity of step motors as the over load may cause the errors On an 43 other hand the servo motor does not have such problems since it is using the close loop as the control theory It can provide the high resolution rapid reaction and high reliabil ity which are more suitable for our temporary storage buffer which requests high preci sion and repeatability The servo motors that picked to use in the buffer get from FESTO Company For each of the axis there is a servo motor to drive the module linear move on the track But ac cording to the different load and other parameters the two axis modules have the differ ent servo motors An EMMS AS 70 S RSB servo motor is chosen to drive the Z axis module while an EMMS AS 55 S TS servo motor is responsible for driving the X axis Both of them are using the same driver name as CMMS AS controller which also pro vided by FESTO company Figure 39 Z axis motor left and X axis motor right 4 4 Servo motor controller The CMMS AS servo motor controller which provided by the FESTO company has been used in the storage buffer as the controller of two servo motor The CMMS AS controllers are special designed to control the FESTO servo motor It allows flexible use in a wide range of different applications This driver can both
35. ed with PLC through the I O interface PLC is the main controller of the system which is located in level 2 It can transfer the messages with S1000 using Modbus TCP protocol S1000 is working as a gateway to the whole system and it can measure the messages from the upper level system It connects the storage buffer to the rest of the system through Ethernet 4 5 1 Servo controller communication method The servo controller has the responsibility to control the servo motor It can receive the commands from PLC and send the feedback signal back to PLC The whole messages transmit are finished by the 1 O interface which was shown in Figure 43 The I O interface that connects the PLC and servo controller is a 25 pin connector There is a certain purpose of every pin In our application there are twelve pins in use These twelve pins are connected to the PLC I O modules and two limit sensors separate ly The useful pins are listed below e Controller release DIN 5 first step to turn on the servo motor e End stage enable DIN 4 used for turning on the servo motor e STOP DIN13 a bit that need to be activated before turn on servo motor e Record selection O DIN 0 storage position selection bit e Record selection 1 DIN 1 storage position selection bit e Record selection 2 DIN 2 storage position selection bit e Start for the positioning process DIN 8 the starting bit for homing and posi tioning process e Limit switch O DIN 6 receive the s
36. er receives the available provider it will bind itself to the provider and the whole process is finished 2 3 2 SOAP Simple Object Access Protocol SOAP is a simple protocol which supports the ex change of structured and typed messages by using XML in a loosely and distributed environment It can aim at replacing the traditional method of remote communications such as RPC based Distributed Component Object Model DCOM 15 XML can make the cross platform communication more convenient the essence of SOAP is just made this communication form normalized 18 ld Application Application SOAP SOAP Network Protocol Network Protocol Connection Figure 7 SOAP connection As shown in Figure 7 the SOAP does not specify the transport mechanism It has to rely on other network protocols and most of them are using HTTP 16 When there are messages that need to be transferred no matter what platform and languages the clients used all the applications will be enveloped into SOAP and sent to the destination through HTTP The structure of SOAP is shown in Figure 8 Figure 8 SOAP Envelope A SOAP message is just a normal XML document it contains three main parts enve lope header and body The envelope can mark the XML documents as the SOAP mes sage The header and body are contained inside of the envelope The SOAP header in cludes the application dedicated information related to SOAP message The SOAP 19 hea
37. er to refresh the warehouse data manually 62 DrawServiceCell sS gt Action SetPalletinfo Input SetPalletinfoReqg SetPalletinfo anonymousSetPalletinfoType uipmentChangeState evt pon ds qn LoadPallet string ILoading CalibrateBuffer PallID string GetState PositionOfPallet string UnLoadPallet string Invoke Figure 56 Control panel of the manual operation Figure 56 shows the control panel of the manual mode As we can see in the figure there are several parameters can be defined PositionOfPallet LoadPallet UnloadPallet and PallI D Two actions can be achieved by editing those parameters manual load and manual unload The two actions can be chosen by editing parameter Load and Unload For the manual load there are three blanks need to be filled in Load Position and PalletID The param eter LoadPallet needs to be set as 1 to trigger the manual load process The rack number and the pallet ID can be saved inside parameter PositionOfPallet and PallID For manual unload The parameters UnloadPallet Position and PallID need to be defined As the trigger of manual unload process UnloadPallet need to be set as 1 The PositionOfPallet and PalllD can restrict the pallet information If the infor mation is successfully refreshed there will be a feedback message shows on the blank located at left corner of the control panel
38. ernal system has been done by using Modbus TCP I O interface and for the connection with the pro duction line the Ethernet has been chosen to achieve this purpose The system connec tion has been shown in Figure 34 1000 ay TCP IP PC O nat Pd Sensors Z axis motor 4 we y MA SZ X axis motor Figure 34 Overview of control layout In this section every components of control layout will be described as well as the communication method of the system The main operation process is separated into loading operation unloading operation manual operation consultation operation The specific operation methods will be explained in detail in the following part 40 4 1 Modicon controller In the buffer system a Modicon M340 programmable logic controller has been used as the central control unit It offers in small box flexibility and integrates functions and provides the Plug amp Work solutions even for third party devices The Modicon controller is widely used in process industries manufacturing and infrastructures 26 Figure 35 Modicon M340 There are some different types of processors can be used on M340 In our case a stand ard environment processor BMXP342020 is chosen to achieve our tasks The BMXP342020 processor provides an Ethernet TCP IP port which can also use for send ing and receiving Modbus TCP messages a RJ45 connector for the Modbus serial link or character mode link and the memory card
39. gram Everytime the WS_Publish is running the S1000 will send a message that contains the variables to the web service The web service will receive the message and shows the relevant variables to the user Another web service operation that used here is INPUT MESSAGES Unlike the EVENTS this operation requires the request from the web service to trigger the re sponse The same as EVENTS operation the INPUT MESSAGES need to be edit ed first The ALIAS as the name of every action and the ST Program as the name of relevant program must be limited so that the program can match the correspond opera tion The request action and response action also need to be defined first Their bodies must contain the exact variables like it in the WSDL file Every time the S1000 receives the request action from the web service the program which related to this action will be triggered to run on time and send the response message back to the service If there is no request message coming the program that associated to this action will never run To send the feedback messages the sentence WS_RESPOND need to be written into the program as the trigger of responding EVENTS Equipment State http www tut fifast robot RobotPortType EquipmentChan Save Edit Remove Addnew UnLoading ST Program UnloadingPro Remove Request action http www tut fifast robot RobotPort Type UnLoadingRequ Edit body Response a
40. gramming language of PLC has some distinctive features Unlike the high level language or the compiled language the PLC language asks not only easy to program but also apt for debugging 23 According to the IEC 61131 3 standard which formulated International Electrotechnical Commission there are five PLC programming languages Ladder diagram LD Func tion block diagram FBD Structure text ST Instruction list IL and Sequential func tion chart SFC 1 2 Ladder diagram The ladder diagram is the most common used PLC program language which is similar with the relay circuit LD can match the electric operation schematic dia gram so that LD has the advantage of intuitiveness Figure 11 shows an example of LD developed in software Unity Pro It means if IO or 2 is true and Il is false the Q1 will be executed Figure 11 Example of Ladder Diagram Function block diagram The function block diagram is a PLC program that similar with the digital logic circuit It uses the function block to express the functions and each function block has the certain functions Figure 12 shows a basic AND function block When both the input A and input B are true the output Q will be triggered A IN1 OUTITAQ B IN2 Figure 12 Example of FBD 3 4 5 24 Instruction list IL language is a mnemonic programming language that similar with the com piled language It composed of operation
41. he pallet up a little bit after the pallet is higher than the stopper the gripper will be pulled back which can be sensed by the sensor at the back of the gripper groove In the meantime the stoppers are reset and the conveyor motor is turned on again After this process the pallet is attached to the robot and both of the servos start to transfer the pallet to the unload position This position is a little bit higher than the target rack to make sure the pallet can be put into the rack The rotary module will turn to left or right side according to the target position right after the robot reach the unload position Then the gripper will be pushed out and now the pallet is right above the target rack After one second the Z axis will drop the pallet on the rack and now the pallet is surrounded by the tilt pillars Till now the robot has finished its job it will withdraw the gripper and the pallet will be left on the rack and fix there because of those tilt pillars on the racks Then the rotary module will be set at the middle position and the servo motor will send the robot to home position wait for next mission During this process the PLC also informs S1000 59 that the command has been achieved so S1000 will store the palletID into the corre sponding rack number and send a feedback message to web service 4 6 1 2 Unloading operation The Unloading operation is another main process of the storage buffer which is respon sible for retriev
42. hen the buffer status changed This means that the feedback mode is working in an initiative mode The S1000 function WS_Publish is fit the requirements and chose to achieve this action Unlike the control panel of other operations there is no need for user to input parameters to obtain the feedback message The user only needs to press the subscribe button to start receiving the state change message of buffer 66 5 CONCLUSIONS This thesis is focusing on established a service oriented automatic storage buffer for mixed production line It is used for enhance the capability of the production line by reducing the bottleneck which coming from the unexpected errors or maintenance The buffer can provide a temporary storage space to store the pallet which will impede the operating of the production line The buffer is composed of a transporting robot a compatible conveyor a warehouse with three level shelves a pneumatic actuation system and a control circuit The main problem of designing the buffer is how to integrate buffer into the production line net and how to achieve the load and retrieve operation The Fastory production line is a web based automatic assembly line To integrate the buffer into this line a FESTO S1000 controller is used in buffer cell as a gateway to the web service Through this controller the command messages sent from web service can be delivered to the executing system and the feedback messages from the buffer can
43. i Jokinen for all his advises and help No matter how many times I troubled him Jani always be there for me without any complain Thanks to Matti Aarnio Luis Gonzalez and Sami Mustalahti for your valuable helping I would also want to appreciate all of the FAST Lab colleagues to give me a friendly working environment Also I want to thanks to my parents and my family who supports my life all those years Thank you for your great understand and patience of my education I would not be who I am today without your love My dear friends Bin Zhang Yuyang Chen Xiaoguang Song Yi Xiong Bingshan Han and Peng Zhang thank you for giving me the best two years in my life I have gained two much from this study career in Finland I would never forget this fan tastic place in my whole life Yansong Guo CONTENTS A A O aE 1 A o ain sc0cyonsrhoeisSaceadyserdecsisesnontsansdtubielasendyteadensanernantuanideubialaseaduseulenninmamntics 9 A A enan ea aed Soeou hs eas be Saas A R ewes hea 11 1 2 Probler Statements A A ada 13 SA o A A 13 kA LES UD A A A 13 23 MINE OLELICAL PACK PTU orcs Sync alta Solas vet aoa eae ol ab nes lcs a ene een 14 Dele Assembly le iii coves hl haanvadbecd eset ian nenibeed E EEEE DEE EEEa 14 Di Ze e o O E O 15 2 3 Service ornent ed ATCHUECHUITS ida 16 2 3 1 Web Service Structure ico 16 Za ADA Pad 17 DS a WS DUS as ee ha ae tt a el Be Sle E ek Ol Ba Sh 19 DoS Ain UDD e aa ea 20 2 4 Programmable Logic Control
44. ifferent from each other in both PLC and S1000 parts This sec 56 tion will explain every operation in detail as well as the program and logic to achieve the tasks 4 6 1 Automatic mode In the automatic mode there are two separated operations Loading operation and un loading operation The Loading operation respond for picking the pallet from conveyor and transfer it to the racks and the unloading operation is used for retrieving the pallet from racks back to conveyor 4 6 1 1 Loading operation The loading operation is one of the most important actions in the buffer system It is used for removing the pallet from conveyor and carrying it to the assigned rack The whole functionality is based on the loading operation since no pallet will be stored into the buffer if the loading operation cannot be completed There are two different parts of actions of loading operation which executed in 1000 and PLC separately The S1000 is working as the message sending and receiving gateway and an information processor It can get the messages from the web service which contains the commands for the buffer After the S1000 receives the message it will analyse the commands and convert the command to the exact actions and send it to the PLC Besides the information about the buffer also stores in the memory of S1000 The PLC on the other hand only shoulders the specific actions without doubting and judgement capabilities The Loading operation contai
45. ignal from limit switch which located at the end of sliding groove It must send the positive signal to servo when the motor 50 intend to move Otherwise the motor will stop and send the warning or error back to servo controller e Limit switch 1 DIN 7 work together with limit switch O as the safety sensor and homing sensor e Ready for operation DOUT 0 send the ready signal to PLC e Motion complete DOUT 1 when the servo motor accomplished its task this bits will inform the PLC that the motion is completed e Error DOUT 3 send the error information to PLC when the motor is stopped by the unexpected situation All the messages transfer between the servo controller and rest of the system are through this I O interface Since there are two servo controllers in the buffer system there are two output modules to send the commands to the servo controllers and one input module to receive the feedback signals from servo controller separately The two proximity sensors which work as the homing and safety sensor are directly linked to the servo motor so when there is a safety problem occurred the motor can be stopped im mediately 4 5 2 PLC communication method The PLC that used in the storage buffer is Modicon M340 It supports the TCP IP for mat messages transfer However the PLC does not have the web service functions It cannot recognize the SOAP protocol as well as WSDL files Because of this shortcom ing the PLC must have a gateway to co
46. ime use required type xs dateTime gt currentState use required gt SETUP gt READY IDLE STARVED gt READY IDLE BLOCKED gt READY PROCESSING ACTIVE gt READY PROCESSING EXECUTING gt DOWN gt ction base xs string gt OFF gt SETUP gt READY IDLE STARVED gt READY IDLE BLOCKED gt READY PROCESSING ACTIVE gt READY PROCESSING EXECUTING gt DOWN gt Figure 59 EquipmentChangeState As we can see in the red block there are seven events in total However since the buffer itself do not need that much events the events READY IDLE BLOCKED and READY PROCESSING ACTIVE are not in used But the element currentState are still contains these two events as the default events for the future use The five useful events are 65 e OFF only used for every time the buffer is power off The event will be changed to others as soon as the buffer is power on e SETUP present the reset and calibrate process during the manual homing pro cess e READY IDLE STARVED when the buffer is free to executing task this event will be triggered e READY PROCESSING EXECUTING this event will be sent to web service when the buffer is executing the missions e DOWN if there is some unexpected error occurred or the motor is stop working this event will be triggered The feedback mode is not working in request respond mode and it can be triggered w
47. ing the pallet from warehouse back to the conveyor based on the web service orders Like the loading operation the process of unloading operation also sepa rated as two parts S1000 in charge of data processing while the PLC responsible for the real complying of the operation Through the web service gateway which represents as S1000 here the PLC can get the operation command and after it finish the mission the feedback message will also send back through the S1000 AAA O aE y 2 Pi Line Control Application eth 192 168 33 60 A800 S File Help DPWS PI Contol SCAN Devices Found 1 MENA reserve MARE SetPalletinfo Input UnLoadingRequest LoadingMsg anon isLoadingMsgT EquipmentChangeState evt ae 4 Lemay saT ype Palletinfo palletid string Loading i CalibrateBuffer Position string GetState uuid add url http 192 168 x y 80 dpws device Subscriptions Figure 54 Control panel for unloading operation The figure above shows the control panel of the unloading operation There are two unloading methods which used in the buffer retrieving by palletID and retrieving by position In the buffer control panel if the user wants to invoke the unloading operation there will be two input parameter available PalletID and Position The two unloading method can be triggered automatically by choosing one of these two parameters If Pal letID is filled and the Position i
48. is may reduce the efficiency of the whole system To make the assembly line more flexible the storage buffer must be used on the line 2 2 Buffer A storage buffer that used on the assembly line is a temporary store area 7 The work pieces can be stored temporarily and retrieved back to the product line automatically The assembly line can be seen as a series arrangement of stages 8 Each stage contains one operation or several operation stations The original input of the system is the input to the first stage After the first stage till the last stage every output of the stage can be seen as the input to the next stage Every stage can work individually thus the break down or failure of one stage will not affect the other stages operations However since all the work of stages is based on the previous stage one breakdown stage may cause a domino effect to the rest of the system It means when there is a stage breakdown the whole system must be shut down to await the repair even most of the stages are in good status and capable to work 9 To solve this problem the buffer can be introduced into the system Figure 5 shows a two station line as the instance By integrated the buffer between Stagel and Stage2 an extra storage space will be acquired When the break down occurred on Stage2 the upstream product can still be produced as long as the buffer has the space to store them So the shutdown of Stage2 will not affect Stagel In the Fas
49. ise the message will not be trans fer successfully In our case the S1000 output register is start with 50 while the input register is start with 1 The figure below shows an example of the Modbus TCP configu ration page Configuration QD0 Friendly name REMOTE REGISTERS Register type Holding register outputs Modbus scanner TCP 1 192 168 7 10 Slave address 20 Serial 1 247 TCP 0 255 Register block start address 50 1 65536 Register quantity 18 1 120 QD0 0 StoreToRack1 QDO0 1 Store ToRack2 QDO0 2 Store ToRack3 QD0 3 Store ToRack4 QD0 4 StoreToRack5 QDO0 5 Store ToRack6 QD0 6 StoreToRack7 QD0 7 Store ToRack8 QD0 8 StoreToRack9 QD0 9 Store ToRack10 Figure 50 Modbus TCP output register configuration page After the above processes have been executed the communication link between PLC and S1000 has been established Now the only thing left for the connection of the sys tem is integrating this storage buffer itself into the rest of the production line 4 5 3 S1000 communication method The Fastory production line is a web based automatic assembly line that contained elev en working cells The connection of each cell is based on web service and controlled by a central controller The communication media in each cell is the INICO S1000 which working as the gateway to the upper level web service S1000 itself as a controller can provide the ability of interaction to the cells with a series speci
50. ki Web_service H W Ang Tailoring DoDAF For Service Oriented Architectures tekij Military Communications Conference 2006 2006 T SEDLACEK A REAL TIME POSITIONING SYSTEM OF MANUFACTURING CARRIERS DEPLOYING WIRELESS MEMS ACCELEROMETERS AND GYROSCOPES 2012 A D Z Davis A comparative study of DCOM and SOAP tekij Multimedia Software Engineering 2002 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 68 D M Davis Latency Performance of SOAP Implementations tekij Cluster Computing and the Grid 2002 Web Services Description Language Access on October 23 2012 Available http en wikipedia org wiki Web_Services_Description_Language W3C Web Services Description Language WSDL Version 2 0 Part 0 Primer Access on October 25 2012 Available http www w3 org TR 2007 REC wsd120 primer 20070626 basics G Saez Web services based data management evaluating the performance of UDDI registries tekij Web Services 2004 Proceedings 2004 J Colgrave External matching in UDDI tekij Web Services 2004 Programmable logic controller Access on October 28 2012 Available http en wikipedia org wiki Programmable_logic_controller F Lei hua Application of Communication Optimization Strategy Based on Cascade PLC MODBUS in Fire Water System of Hydropower Station tekij Intelligent Compu
51. ler cei eet eee te ee 20 DAM PIC A A AS 21 2 4 2 PLC AA A A 22 2 4 3 PLC programming language ccconnnonccccnnnccnnnnnnnonancnnnnnnonnnananananoss 22 3 Mechanical layout implementation cesta bi 26 3 1 Overview of the buffers units ts A A A 26 A A AR A E NIRO 27 Doin l MOOSE a A A II PI EA A 28 o A robot remanere Sete eo ca oy oe nee areas 30 34l XK ARS mod l ceci iii ASE EEAS DES 31 34 2 RA A O 33 A O erin ti n ario isset 36 3 6 End effector module tices ties tas ties esheets ahead 37 A Control SYStem scsi tiie siers Geass teat Ses radianes 39 4J WIGGICON COMMONER S258 eee a A O N 40 4 2 INTENSA di 41 4 3 Servo MOto neen aaao utalos a tube a a Eri 42 4 4 Servo motor controller siscsciccsscssassesctas carvers sccshcraavaiveis iv cshctaasateetsevasboeaasaevens 43 4 4 1 Festo Configuration tool eeeeeesesncccceeeeeeeeeeeenneeeeeeeeeeeeee 44 4 4 2 Servo motor control method cccceeeesseeeesesseeeeeeeeeeeeeeeeeeees 46 4 5 System communication method nenes td a 48 4 5 1 Servo controller communication method ccccceeeeeeeeeeeees 49 4 5 2 PLC communication method a Aaa a eas 50 4 5 3 S1000 communication method cccceceeeeeeeeeeeeeeeeeeeeeeeeeeees 53 A Gs Buffet IDEA 55 A 6 1 AUtOMatic modes eanes a a a e a an bene 56 46 2 Mantial mode ci ea 61 4 6 3 Consultation Mode ui A A id 63 4 6 4 Feedback IM canas 64 Dl CORCIUSIONS ta AA AAA 66 Sele A AAA A baie 66 I
52. meters above the components which fit the orders are chosen as in Table 5 Table 5 Components of the Z axis system Axis DGE ZR 25 Guide Ball Bearing Motor EMMS AS 70 M RSB Controller CMMS AS C4 3A In addition there is another problem of mounting the servo motor To avoiding the col lision between the end effector and the motor it has to be assembled on the top of the frame since it is the only place has the space for the motor There are three potential places to mount the motor based on the frame design back face up face and the side 35 face Since the Z axis module is installed on a rotary part there will be collision be tween motor and the X axe if mount the motor on the top face Besides mount the mo tor on the side face will increase the inertia of the module which means more pneumatic power of the rotary module is needed So the ideal place for the motor is back face To fix the motor on the frame a mounting plate and a holder are used in the design There are also two pulleys and a belt has been used for transferring the motor power to the system in the right direction The Figure 27 shows the detail of the motor module 2 TA Figure 27 view of the motor assembly module The same as the X axis module Z axis module also has three proximity sensors Two of them are assembled on the top and bottom of the frames as the limit switches The bot tom limit switch also works as the homing senso
53. ming method The limit switch pattern uses two negative proximity sensors to detect the motor posi tion When the homing process starts both of the sensors are positive since the motor is 45 not near them and the motor can be moved in both directions according to the pre set up in the FCT When the motor arrivals to one of the sensors that sensor will recognize the coming of motor and the signal which is sent to the controller are turned to be negative so the controller will notice the motor is arrived to the homing point Then the controller will control the motor inverse the rotate orientation and stop the motor right after it out of the sense range of the sensor After the motor stop the whole homing process is fin ished and ready for the work After the homing process finished the motor operation mode can be chosen either man ual mode or device control First the manual mode should be chosen since the controller is not be configured yet In the manual mode the user can define the moving velocity and distance The destination positions can be stored in the controller memory once the user obtains the desire positions The CMMS AS controller can store up to 63 positions and for each of them there can be a customized profile to depict motion of the motor There are eight parameters can be records into the position profile they are e Drive velocity e Drive acceleration e Drive deceleration e Smoothing e Time e Start delay
54. ngle task which they are expert in instead of knowing every thing of a product Basic assembly line model is shown in Figure 4 Station 1 Station 3 Conveyor EJ EJ Flow Station 2 Station 4 Figure 4 Basic assembly line As we can see in Figure 4 the two basic elements of the assembly line are conveyor and work stations The conveyor is responsible to transfer the raw and product among the different work stations It is like a bond to combine the individual work station together In this figure first the unfinished product are loaded on to the conveyor and sent to WS1 The worker on WS1 starts to do the partial work which he is responsible Then this product is sent to WS2 WS4 in sequence When it reaches the end of the conveyor 1t becomes a finished product For each work station the conveyor will stop for a cer tain time to make sure the work can accomplish their work This stopping time is called cycle time Nowadays with the robotics and communication technologies rapid progress the tradi tional assembly lines are getting more and more automatically Mass of the robotics is instead of the people working on the line with better precision higher efficient and low 15 er cost But no matter how the technology progressed it is still cannot be ensured the system can work well without any problem If one of the stations on line turned out er ror the whole line has to stop and wait until the mistake solved Th
55. nn nn nnnnos 49 Figure 48 Modbus TCP data format si iui tote eesates Wa E E ae Medes 51 Figure 49 Set up of the Modbus TCP pott oooonnnnnnnccococonononannn non nono nono nono nono nn n nn nro nn nn nnnnnos 51 Figure 50 Modbus TCP output register configuration page ooeec 53 Figure 31 S1000 WSDL file ritos alonso E aaa E aaaea aaan 54 Figure 52 Web Service edit PAE seectuek serena tbenssete tenses 55 Figure 53 flowchart for loading operation 1ssssssssssssssssssssssssssssssssssssssssssnssseesees 57 Figure 54 Control panel for unloading OperatiOO ooooooonncncononononanonn nono n nn nro non nn nn ono nnnnnos 59 Figure 55 flowchart for unloading operation ooooooonnnonononononanononnnnnn ono nono nono nro nn nn nro nnnnnos 60 Figure 56 Control panel of the manual operation ooooonnnccnnnccooononoonoono non nono nono nn nn nn ono nono 62 Figure 57 Control panel for PalletInfO action ooonnnnnnnnnnnnnnonananananaaanon nono ono n nn nono nn n nro nro 63 Figure 58 Control panel for GetState action oooooooonccccocooooooaonoonnono nono nono nro n ono nn rn n nn nnnnnos 63 Figure 59 EquipmentChanceStale stas iio 64 LIST OF TABLES Table 1 Transmission primitives cocccnnnnonncccnncncnnnnnnnnncnnnnncnnnnnnnannnnnnnncnonnnnnnns 20 Table 2 System requirements of X axis system 17 ooooooooooccccccccnnnooonoccnonocccnnanons 32 Table 3 Components of the X axis SySteM ooooooonnnocccnnonocccccnononnccnnonancnoncnnnnncnnnnnns
56. nnect to the web service which used as the pro duction lines control theory The 1000 on the other hand support both the web service and Modbus TCP message transmissions which make it becomes the ideal gateway in our system Modbus is a serial communications protocol that published in 1979 by Schneider Com pany It is used as a field bus to connect the industrial electronic devices and it is now one of the most commonly communication protocols that used in the industrials The communication protocol used here to communicate the PLC with 1000 is Modbus TCP It is a variant of the Modbus protocol that used for communications through the TCP IP network The frame format of the Modbus TCP is shown in Figure 48 51 Modbus TCP Frame Format Name Length Function Figure 48 Modbus TCP data format In our system both of Modicon PLC and S1000 support the Modbus TCP data trans mission The physical link of the PLC and S1000 is a standard port 502 To establish the communication link some of special functions need to be used on both side device pro grams The BMXP342020 processor which used in the system has the Ethernet port that inte grated in itself so the physical can easily set up by plug in a port 502 cable The com munication functions should be set in Unity Pro software The function for the Ethernet port can be defined as Figure 49 Project Browser 8 3 Project Ey Configuration O EA 0 PLC bus El o Bmx xBP
57. ns two different positioning methods Sequential position ing and positioning in order When the user wants to launch the loading process there are two input parameters that need to be given PalletID and position PalletID is the pallet ID that needs to be stored and position is the rack number that the user ex pects the pallet to be stored The PalletID must be defined correct otherwise the Un loading process maybe could not find the certain pallet The Position is not a neces sary compulsory parameter If the position blank is left empty the Sequential posi tioning method will be chosen as the Loading method The whole buffer contains eight een racks with the number from one to eighteen while the Rackl is the nearest rack and the Rack18 is the farthest rack According to the energy saving principle the 1000 will start asking the nearest free rack since the nearer the rack is the less energy will be con sumed If the Rack1 is occupied the Rack2 will be queried and so on Until the free rack is found that rack will be the destination for this time s positioning If all the racks are occupied the S1000 will reject the request for loading process and send a feedback message to explain the reason for rejection The other one positioning method is posi tioning in order It means the user defined the rack number for the loading process In this situation the parameter position must be filled
58. ntains the address contact information and known identi fiers The yellow page includes the industrial categorizations that based on standard taxonomy while the green page specifies the technical information of web service which offered by the company 2 4 Programmable Logic Controller The Programmable logic controller is a digital computer which used for the automation of electromechanical processes 21 It uses the memory unit to store the program to execute the logic calculate sequential control timing and the counting orders Further more it can control various kinds of machines producing processes through the digital or analog I O interface Since the PLC is based on CPU the PLC has plenty of computer features But the work mode of PLC is very different from computer Computer usually uses the command 21 oriented working mode such as keyboard scan mode or I O scan mode If the keyboard is pressed or I O is changed the computer will operate the related subprogram Other wise the computer will keep scanning and waiting Unlike the computer the PLC is using the cycle scan mode For each program CPU executes from the first statement to the last statement in sequence which called a cycle time 2 4 1 PLC structure The PLC as a microprocessor based device has a similar internal structure to other em bedded controllers and computers Figure 10 shows the main structure of the PLC The PLC consists of the main power CPU Mem
59. nted architecture SOA in the thesis SOA is a component model which is a framework for designing developing applying and managing the distributed sys tems By applying the SOA technology into the buffer the buffer can be easily inte grated into the production line The storage buffer described in this thesis can per form in four operation modes including Automatic mode Manual mode Consulta tion mode and the Feedback mode It provides the functional completeness for the whole production line and exhibits adequate intelligence and performance The results of the thesis show e 1 The designed control system of the storage buffer e 2 The communication methods between the buffer and the existing produc tion line e 3 The realization of the four operation modes of the buffer PREFACE It has been more than two years since I have been to Finland as an international master student Now this wonderful and joyful journey is close to the end After this two years study on this occasion I want to express my great thankful to my teacher my parents friends colleagues and all the people who always supports me and helps me going through all these years First of all I want to give my greatest appreciation to Prof Dr Jos Luis Martinez Lastra Thank you Thank you to give me the opportunity to study in Finland to study in department of Production Engineering and work in the FAST lab Secondly I want to gratitude to my supervisor Dr Jan
60. or storing the pallet Fig 15 shows the buffer layout overview 27 Figure 15 Overview of the buffer 3 2 Cell of the buffer The cell that used for containing the buffer system is the same as the rest of cells on the production line The original purpose of the cell is to carry the Sony SRX 611 robots To host the buffer a few specific modifications have been applied on the base metal plate Figure 16 shows the CAD view of the buffer cell Figure 16 CAD drawing of Cell 28 The cell is surrounded by the plastic windows which are easily monitoring the working status of the buffer and the safety issue is also token into considered The windows are mounted on the cell frames in a slide mode and there are safety switches installed on the corner of each window to make sure the windows will not be accidently opened during the buffer is working Figure 17 Safety switch A cabinet is attached below the working area which contains most of the control com ponents and the wires There are also three buttons on the door of the cabinet The red one is for emergency stop green button is the start button and the yellow button is for the system reset Another plastic box is mounted on one of the cell foot that used for containing the control circuit of the pneumatic valves The main valve of the pneumatic system is under the plastic box that responsible for the pneumatic power of the buffer Figure 18 control cabinet and pneumatic valve
61. orce valve and pressure valve which can be assembled on the pipe as a post work There are two FESTO SME series magnetic proximity sensors are mounted on the side grooves of the rotary module They are used for detecting the side positions of the mod ule one is for 0 and another one is for 180 These sensors can determine if the rotary module reached the load unload position and ready for release the fork The sensing signal can be send to PLC to trigger the next step execution The assemble position of the sensor can affect the sensing position It allowed some tiny error since the reaction of the PLC and the fork need about half second and during these times the rotary mod ule can reach the ideal position easily 3 6 End effector module The end effector module is the pallet carrier which contacts the pallet directly It is re sponsible for picking dropping the pallet from to conveyor and racks It consists of the pneumatic end effector linear axis a fork and mechanical attachment parts Figure 31 shows the 3D module of the end effector module Figure 31 3D view of end effector module A FESTO DGC 18 250 KF YSRW A pneumatic axis has been used on the end effector to provide the horizontal movement of the fork The pneumatic axis is attached to the bottom of a mechanical attachment part which mounted on the sliders of Z axis module The mechanical attachment part is a flat plate with two standard FESTO mounting parts on each side
62. ory I O units peripheral I O interface and the expansion interface Arithmetic Unit Control Unit Figure 10 Structure of PLC CPU CPU contains the arithmetic unit the control unit memory and the bus which used for transferring the data between them CPU is the core of the PLC which working as the central nervous system Each PLC has at least one CPU It receives and stored the user program and data accordance with the system program of the PLC The status and data can be gathered through the on site input device by the scanning mode and stored into specific memory In the meantime the CPU can also diagnose the working status of power and internal circuit and the programming syntax error When the PLC is running first the CPU will receive the input devices data using scanning mode and store the mapping area Then the CPU will read the user program statement by statement from 22 the user program memory After all of the user program has been executed the output command will be sent to the corresponding output devices The CPU will keep the exe cution cycle until the PLC powered off Recently years the large scale PLC is using the dual CPU as the redundant system or the triple CPU as the voting system to enhance the reliability of the PLC Power The power module plays an important role in the PLC system It supplies the working power for the PLC circuit Besides it can also supply the 24v power for input ci
63. pallet After this move ment the gripper will be pushed out into pallet groove and the Z axis module will lift the pallet up a little bit so that the pallet can be carried out of the rack Then the gripper will be pulled back with the pallet and the rotary module will turn to the middle position The servo controller drives the X module motor going to the home position and Z mod ule drives motor going to the retrieve position When this action is accomplished the conveyor will stop and the stopper is pulled in Then with the help of Z axis module and the end effector the pallet will be retrieved back to conveyor After the whole unloading operation is over the PLC will inform S1000 that operation is success so the S1000 will remove the palletID from the rack and set that rack as free Otherwise the S1000 will treat the operation as failed and the palletID will still be stored inside the memory of S1000 4 6 2 Manual mode In the factory although there are a lot of protection measurements to keep the produc tion line working properly there are always some unexpected errors or situation oc curred When these situations happened the staff may need to manual load and retrieve the pallet from buffer The S1000 as the warehouse information memory cannot sense these manual arrangements and which means the S1000 cannot refresh the data about these operations To fix this problem a manual mode choice has been developed to give a window for the us
64. r which as part of the servo system The last sensor is a Festo proximity sensor used for sending the feedback signal to PLC Figure 28 shows the pictures of these two types sensors a i Figure 28 View of the proximity sensor 36 3 5 Rotary module The rotary module of the system is located between the Z axis module and X axis mod ule that consists of the pneumatic rotary drive and two connection parts that fix the module on the slider which mounted on the bottom X axe Figure 29 3D view of rotary module As describe in the previous chapter the warehouse is two separate shelves that located on the side of the operating robot This condition asks the operating can rotary to each side to make sure the pallet can be loaded on both of them A FESTO DRQD 40 180 YSRJ A AR FWZ1 twin piston rotary drive is used here to achieve the design purpose This rotary module can provide a 180 rotation range to fulfil the demands of the system With the help of rotary module the end effector can reach three positions 0 90 and 180 Figure 30 DRQD rotary driver 25 In the rotary driver there are two valves which controlled by the PLC The drive can be rotated by opening and closing the valve The two side positions can be reach by only release one valve while the middle position needs to adjust both of the valves Since the 37 driver is driven by the pneumatic both of the speed and the force of the module can be adjusted by the f
65. ration section After the homing the buffer itself is ready for operating When the unloading command is coming from web service the 1000 will check the status of the buffer If the buffer is busy it will refuse the request which sent from the web service and give them a feedback message about the rejection reason If the buffer is free to work the S1000 will start to check the detail about the command about which unloading method the command is request Under the retrieving by palletID method the S1000 will check its memory about whether the ordered pallet exists If not the S1000 will send a message says that the buffer does not have that pallet and reject the request If the pallet exists the S1000 will find the location of the pallet and send it to the PLC Under the retrieving by position method the 1000 will check the certain position to find the requested pallet When the asked rack is empty S1000 will treat the command as an error and refuse it in the meantime send the feedback information back to web service Otherwise the S1000 will send this position to PLC and request the PLC retrieve the ordered pallet The Modicon PLC will start the robot to go to the request rack as soon as it receives the retrieve order When the PLC receives the signals from the servo controller that the movement of motor is finished the pneumatic actuator inside the rotary module will rotate the robot so that the gripper can face the groove of the
66. rcuit The input power can be classified as the alternating current 220VAC or 110VAC and direct current usually 24VDC T O module The I O module is the interface between the electrical circuit and PLC I O circuit is integrated on the I O module and the input register reflects the status of the input signal while the output point reflects the status of the latch The input module can switch the electric signal into digital signal and the output module can switch digital signal into electric signal The I O can be separated as e Digital signal only contains 0 and 1 value The voltage can be 220VAC 110VAC and 24VDC It can be relay isolation or transistor isolation e Analog signal the signal is the continuous change value 2 4 2 PLC communication PLC can establish the net through a 9 pin RS 232 interface EIA 485 or Ethernet 22 There are plenty of protocols that can be used for transferring the data through PLC and the other devices such as Modbus Profibus 23 Devicenet and BACnet Since there is still no standard for delimiting the PLC communication protocol usually the different PLC has some certain protocols which defined by the companies that produced the PLC Most modern PLCs can communicate with some other system over a network such as a computer running Supervisory Control and Data Acquisition SCADA system or web browser 2 4 3 PLC programming language Compare with the normal computer programming language the pro
67. rotocol 20 e Port Defines the address or connection point to a web service which usually represented by a simple HTTP URL string e Operation Defines the SOAP actions and the message encoding method WSDL supports four message transmission primitives Table 1 shows the description of each primitive Table 1 Transmission primitives One way operation Endpoint receive the message without re quest Request response operation Endpoint receive the request message then send response message Solicit response operation Endpoint send the request message and receive the response message Notification operation Endpoint send the message and do not wait the response 2 3 4 UDDI The Universal Description Discovery and Integration which short by UDDI can sup port open frameworks for business to store advertise and retrieve pertinent services 19 Web services can get the directory services from UDDI which offered by businesses 19 It was originally proposed as a core standard of web service UDDI is an open in dustry initiative for enabling the businesses to publish the services and the other busi nesses to find the useful functions The core module of UDDI is UDDI businesses registry it used the XML documents to describe the companies and the services they supplied Conceptually the UDDI busi ness registration consists of three components the white page the yellow page and the green page The white page co
68. ry proximity sensors have been assembled on each end of the top axe as the limit switch Besides the sensor located on the conveyor side is also working as a homing sensor Another Festo proximity sensor has been mounted above the home position of the X axis It is used for sending the input signal to the PLC The figure of sensors is shown in Figure 25 Ps iri Figure 25 View of proximity sensors 3 4 2 Z axis module Z axis module is a set of components that can supply the vertical movement for pallet to reach the different shelves The Z axis module consists of an AC servo motor which mounted on the top corner of the frame a frame contains two DGE ZR25 axes which allow the end effector move along the Z axis and two sliders which support the rotation to connect the Z axis module with the X axis module Figure 26 shows the 3D view of the Z axis module 34 Figure 26 Z axis module The same as the X axis module the components of Z axis module also chose from FESTO Company The parameters that used in the Positioning drives to determine the suitable combinations of the parts are shown in Table 4 Table 4 the parameter values that used in Positioning drives Assembly position Vertical Maximum moving mass 3kg Usable length 370mm Necessary repetition accuracy 0 1mm Axis type Gantry axis Assembly position Up or down Mass position 450mm on Y axis 175mm on Z axis According to the para
69. s blank the unloading method will be set to retrieve by palletID When this method is chose the S1000 will start to search whether the request pallet exists If it is not in the warehouse the S1000 will inform the web service with a 60 rejection message On the other hand if the Position is given and the palletID is unde fined the method retrieve by position will be the option Unloading command coming Blocked Reject the request Starved Retrieve by palletID Retrieve by Unloading position ethod Request pallet exis Request position is full Reject the request Send the Unloading position to PLC Reject the request Send the robot to requesting position Set the Send x axis stopper de cie se conveyor elease gripper ome position ELE gate motor set the z axis robot to release position load the pallet retrieve the pallet back to conveyor Figure 55 flowchart for unloading operation Withdraw gripper set z axis to home position reset gripper and conveyor Figure 55 is the flowchart for the unloading operation The same as the loading opera tion the whole process can be divided into two parts S1000 part and PLC part When the buffer is powered up the first time there will always be a homing process to make sure the robot is at the right starting position The way for homing is described in the 61 loading ope
70. slot As the central control unit BMXP342020 is connected to INICO S1000 through Ethernet port with the Modbus TCP messages Also it is connected to PC through the USB port using TCP IP protocol There are also three Input slots and three Output slots are attached to the M340 platform The servo motor driver can connect to the PLC through those I O interfaces as well as the sensors and the actuators Figure 36 shows the BMXP342020 processor and the I O slot modules Figure 36 BMXP342020 left and 1602 DDI O right module The Unity Pro software has been used for programming the PLC It is developed by the Schneider Company and supports all the five IEC 61131 3 PLC languages In our case the Structure Text language has been used since it is easy to program the sequence con trol by using ST language All the PLC programming can be done by using Unity Pro as well as setting the communication to 1000 and the PC 41 4 2 INICO S1000 The S1000 is a programmable Remote Terminal Unit device that provided by INICO company It can offer process control capabilities and the Web based HMI It has a 32 bit CPU and 8MB flash memory for user programs and data storage The S1000 used in this thesis is the basic module which has an Ethernet interface a 12Mb USB port 8 dig ital inputs and 8 digital outputs 27 Figure 37 S1000 with wireless antenna S1000 is a web based controller that all the configuration and programming are defined through
71. tation Technology and Automation 2009 2009 L L Wang Development of a distributed control system for PLC based applications tekij Machine Learning and Cybernetics ICMLC 2012 E O SAGIR Design and implementation of a random access buffer for mixed production Tampere 2009 FESTO Access on June 24 2012 Available https www festo com cat en gb_gb data doc_engb PDF EN DRQD B_EN PDF schneider electric Access on July 15 2012 Available http www2 schneider electric com sites corporate en products services automation control products offer range presentation page c_filepath templatedata Offer_Presentation 3_Range_Datashe et data en shared automation_and_control modicon_m340 xml INICO S1000 user manual Access on June 14 2012 Available http www 1inicotech com doc S 1000 20User 20Manual pdf wikipedia servo motor Wikipedia Access on August 18 2012 Available http en wikipedia org wiki Servo_motor FESTO Access on August 18 2012 Available www festo com FESTO Festo Configuration Tool CMMS AS plug in Access on August 19 2012 Available www festo com
72. the upper level web service it will first check the buffer status If the buffer is not in the starve condition the S1000 will refuse this request and send the rejection reason back to the web service If the buffer is ready to work the S1000 will check the loading command method When the command is using Sequential positioning method 1000 will check whether there is a free rack for the pallet If so the S1000 will send the loading command to the PLC with the rack number Otherwise it will refuse this order and send the feedback message to web service When the command is using po sitioning in order method the S1000 will check if the specified rack is empty If so the 1000 will send the loading command to PLC with position data If not S1000 will send the reject message back to web service All the data processing will be finished in 1000 Modicon PLC is only responsible for the real complying of the web service orders When the PLC receives the loading com mand from 1000 it will wait until the pallet coming Then the conveyor will stop and the gripper will be stretched out the sensor in front of the end effector will sense the signal when this process is over The stopper at the entrance of buffer will come out to stop the other coming pallet so they will not affect the loading process and the stopper in front of the end effector will be pull back Now the pallet is free to be carried away First the Z axis motor will lift t
73. the web browser The S1000 can be programmed with the IEC61131 3 Struc tured Text language which also chose to be the programming language of Modicon M340 PLC Unlike the real PLC controller the S1000 does not have the unique pro gramming software All the programming operations are working through the web browsers such as IE and Firefox The communication from 1000 to PLC and the web service will be explained in the following sections in detail The S1000 used here is like a gate way that connecting the PLC to the web service It can receive the commands from upper level web service and determine whether or not send the command to PLC The main interface used here is the Ethernet port since 1000 is not directly linked to the actuators But still one of the input interfaces is used for receiving the signal from a system relay to inform S1000 of the motor status There are two different kinds of variables can be defined in the 1000 Global variables and the Retained variables 42 The global variables can be shared by all the programs and in 1000 no local variables are allowed Global variable supports five different type variables INT BOOL DINT REAL and STRING With the help of global variables the S1000 can achieve most of the tasks but the global variables cannot be stored if the S1000 is powered off Accord ing to this leak the Retained variables are introduced toS1000 The retained variable has the powered off protection The data
74. tory line since all the cells have the Bypass function the conveyor itself can work as a buffer However the capacity of the conveyor is limited To enhance the ca pability of the Fastory line another dedicated buffer is designed in this thesis Buffer Stagel Stage2 Figure 5 Two station Buffer 16 In the modern manufacturing line it is very common to use the buffer to enhance the flexibility of the line The buffer can be used among the work stations to store the in termediate products Moreover it can also be located at the beginning or end position to collect the raw material or completed product In this thesis since the Bypass function has been used in every station only one buffer is introduced into the line and it is enough to serve all the stations 2 3 Service oriented Architecture Service oriented architecture SOA is a component model The SOA is the replaces model of the object oriented model It is a framework for design develop apply and manage the distributed systems It combines the different function units service of application together with the help of well defined interfaces and protocols The interface is defined in a neutral way which independent of the hardware platform operation sys tem and programming language This characteristic makes services which constructed in such systems can interact in the unified pattern This neutral interface which is not binding on the specific realization
75. trical control system to complete the scheduled processing tasks A typical au tomatic manufacturing line must include several units feed unit transportation unit processing unit assembly unit and storage unit The storage buffer that used in the automatic manufacturing line can provide more flex ibility for the producing arrangement It can support more producing functions which related to scheduling cycle time machine reliability and economic run sizing 4 The buffer can provide a temporary storage space for the raw material intermediate parts or 11 final products With the aim of the buffer the automatic manufacturing line can work smoothly 1 1 Background A service oriented architecture SOA is a set of principles and methodologies for de signing and developing software in the form of interoperable services 5 Nowadays the SOA is widely used in the industrial producing This technology can enhance the reliability reduce hardware acquisition costs leverages existing development skills Accelerates movement to standards based server and application consolidation and Pro vides a data bridge between incompatible technologies By using SOA the automatic manufacturing lines can obtain the ability to create a self recovery infrastructure to re duce the management cost Also this methodology can provide real time decision making applications Figure 1 shows an automatic manufacturing line in FAST lab Tampere University of
76. vo controller The servo motor can only recognize the rising edge of the Start for the positioning pro cess so to make sure the servo controller can separate the different positioning com mands two timers with different usages and a set reset function has been used in the PLC programming The programming software used for Modicon is Unity Pro S In this software the pro gram has been described in ST language The timers used here are TP and TON in ST language TP function is depicted as Figure 44 TP_Instance IN TriggerPulse PT PulseDuration Q gt Output ET gt InternalTime Trigger pulse Present pulse duration Output value Time variable Figure 44 Pulse function in Unity Pro 48 TP function is used for setting a positive pulse as the output of TP function the duration of the output is defined as the PT The brief description of the function is when Trig gerPulse becomes true the Output is triggered and will remain the status as PulseDuration value no matter the input TriggerPulse is on or off Another timer func tion that used in the program is TON as shown in Figure 45 TON_Instance IN StartDelay PT PresetDelayTime Q gt Output ET gt InternalTime Input to start the delay Set the delay time The output variable Time variable after the delay time Figure 45 Delay function in Unity Pro TON function is used for acquiring a delay period before the output value is turned to true The delay time can be pre
77. ween buffer and the centre control ler of the line e How to design the control logic to make the buffer fit the specific order of the assembly line 1 3 Objectives This thesis focus on three objectives 1 Design the mechanical components which based on the previous work 2 Establish the communication between main controller of line and the buffer 3 Design and implementation the particular program of the buffer controller and gate way device INICO 1000 All the work has been done based on the Fastory line in FAST Lab Tampere University of Technology Finland 1 4 Thesis Outline The thesis is organized as follows Chapter 2 gives a theoretical background of the as sembly line buffer and the service oriented architecture Chapter 3 describes the me chanical layout implementation of the buffer The control layout with the communica tion methods and system operations is presented in Chapter 4 Conclusions and limita tion of this thesis are given in Chapter 5 as well as some suggestions about the future work 14 2 THEORETICAL BACKGROUND 2 1 Assembly line Assembly line is one of the main supply chains of the industry It contains several workshops and stations where each station consists of many different tasks 6 Henry Ford is the first person who invented the assembly line in the early 1900 This technol ogy revolutionised the way that the factories made By using the assembly line workers are allowed to focus on si
78. with expected rack number If the S1000 received the rack number it will start to search if this rack is free or not If it is free the loading operation will begin otherwise the S1000 will reject the request since 57 the wanted rack is full Figure 53 shows the flowchart of the main actions of the loading operation Start Done Yes Buffer Blocked Reject the status request Starved Pallet Loading Positioning in order ethod Sequence positioning The request No Reject the position empty Free rack finding request No Reject the Send the Loading request position to PLC No wait for the pallet coming Pallet oming Start the release process Set stopper launch gripper carry the pallet Send robot to the home and transfer it to the a2 position release position load the pallet onto rack Figure 53 flowchart for loading operation 58 As we can see in the flowchart when the buffer is powered on the buffer needs to be homing first To achieve this process the user can choose either using the reset button on the control cabinet or using the calibrate operation in the software By this activity the special robots of buffer will be sent back to the home position which mean when the gripper stretches out it can load the pallet onto the fork from the conveyor After that the buffer is ready to receive the pallet When S1000 detects a load command coming from
79. work in point to point mode or master slave mode with single or multiple axis synchronised contour drive 29 X1 I O Interface i i Serial Port 4 CANopen X2 Increment generator Input Figure 40 servo controller with communication interface 44 As we can see in Figure 40 there are four mainly communication interfaces can be used for controlling the servo driver X1 is a 25 pin I O interface that used for communi cating the controller with PLC X2 interface is used for connecting the controller to the servo motor The serial port is responsible to set the link between the PC and the con troller Also there are some fieldbus can be used here such as CANopen Profibus and DeviceNet The servo controller can be directly linked to the PLC through a serial USB convertor After connecting the PC to controller and installing the FCT software the configuration of servo controller can be easily starts 4 4 1 Festo Configuration tool An intuitive graphic depictions and pictograms software Festo Configuration tool FCT has been used here to configure the servo controller The FCT graphical interface can be seen in Figure 41 Ba Festo Configuration Tool testmotor z Project Component View Extra Help J Ag 3 Za ine nie Projects 2 zaxe xaxe a f cums as zaxe 5 Configuration Controller Type CMMS AS C4 3A E E Application Data 7 Option Slot In gt EP Axis i

yansong guo design and implementation of a service

Contents

Download Pdf Manuals

Related Search

Related Contents