Exercise 10. Linear Slides EXERCISE OBJECTIVE

Transcription

1 Exercise 10 Linear Slides EXERCISE OBJECTIVE In this exercise, you will learn to use a linear slide. You will learn how to use the Linear Slide, Model 5209, to extend the work envelope of the Servo Robot. In the Procedure section, you will experiment with the operation of the Linear Slide. You will design a flow chart to create a program in which many external devices are used to simulate a transfer and assembly process. DISCUSSION Since the robots have no body, they cannot attain objects farther than the length of their arm. The linear slides act as legs to expand the work envelope of the robots. The Linear Slide of your training system is shown in Figure It consists of a mobile metallic base on which the Servo Robot is mounted. The base slides on two transverse shafts via four linear ball bearings. The base is driven by a servo motor via a lead screw. Figure Linear Slide. The servo motor is of the same type as those that drive the Servo Robot and its control is also quite similar. 10-1

2 Connection and Configuration The Linear Slide connects to CH 1 or CH 2 on the Robot Controller. Once the connection is made, the Robot Controller must be configured to detect the Linear Slide. To configure the Robot Controller when using the Hand-Held Terminal, press the 5 key in the Main menu to select Configuration. In the Configuration menu, place the cursor beside the channel where the Linear Slide is connected, and press the Enter key as required to select L Slide. Press the S key to save the configuration. To configure the Robot Controller when using Robotics, select the Hardware option in the Options menu. Select Linear Slide in the selection field of the channel where the Linear Slide is connected. Click the Save button to save the configuration. Operation The operation of the Linear Slide is controlled by clicking the CH 1 or CH 2 arrows in Robotics or by pressing, on the Hand-Held Terminal, the 7 or Z keys if it is connected to CH 1, or the 8 or / keys if it is connected to CH 2. Like the Servo Robot, the Linear Slide must be hard homed at the beginning of each session. Make sure that the Servo Robot has sufficient free space to move when executing a hard home positioning. The speed is controllable the same way as the motors of the Servo Robot. Since the position of the Servo Robot depends on the position of the mounting base of the Linear Slide, their position must be saved simultaneously. Unlike the Rotary Carousel, the Robot and External Device check boxes must always be enabled when your Servo Robot is used with the Linear Slide. Task Commands In this exercise, you will be introduced to the Message task command. Message: This command displays the string parameter data in the Message field of the Task Status window. The Message command does not stop execution of the program, so if you need the user to respond to your message, follow the command with a DELAY 0 instruction. The syntax and the parameters associated with the Message command is as follows: MESSAGE <string>. Example: MESSAGE FEED THE PNEUMATIC FEEDER. Procedure Summary In the first part of the exercise, Set-up, you will install and connect the equipment. In the second part, Experiment with the Linear Slide, you will experiment with the Linear Slide by creating a program in which the Servo Robot picks up parts from the Gravity Feeder and transfers them in a container located at the other extremity of the Linear Slide. 10-2

3 In the third part, Additional Experiment - Simulation of an Assembly and Transfer Process. You will use the Gravity Feeder, Pneumatic Feeder, Rotary Carousel, Belt Conveyor, Linear Slide and Servo Robot to create a program that simulates an assembly and transfer process. You will design the flow chart, prepare the connection diagram, and create the program. In the last part of the exercise, Shutdown Procedure, you will shut down the system. EQUIPMENT REQUIRED Refer to the Equipment Utilization Chart, in Appendix A of this manual, to obtain the list of equipment required to perform this exercise. PROCEDURE Set-up CAUTION! When you work with moving equipment, make sure you are not wearing anything that might get caught, such as a tie or jewelry. If your hair is long, tie it out of the way. G 1. Install the Linear Slide and Gravity Feeder as shown in Figure

4 Figure Location of the equipment on the Work Surfaces. Note: Refer to the Equipment Layout shown in Figure E-2 in Appendix E. 10-4

5 G 2. Mount the Servo Robot on the mobile base of the Linear Slide as shown in Figure Figure Mounting the Servo Robot on the Linear Slide. G 3. Make sure that the emergency stop button is released (in the up position) and easily accessible. G 4. Connect the equipment as shown in Appendix B. Refer to the User Guide of your training system for detailed instructions. G 5. Connect the Linear Slide cable to CH 2 on the Robot Controller. Make sure the connector is all the way in before it is screwed. Experiment with the Linear Slide G 6. Turn the Robot Controller on. Note: Use Robotics to perform the following steps. G 7. Configure your Robot Controller to detect the Linear Slide on channel 2 as described in the discussion of this exercise. G 8. Execute a hard home positioning. Note: You must be very careful when using the Linear Slide. Make sure that the movement of the Servo Robot does not interfere with the movement of the Linear Slide. G 9. Move the Linear Slide in both directions using the CH 2 arrow keys. 10-5

6 G 10. Feed the Gravity Feeder with parts. Place a metallic can with the opening on top at position (R9,C3). G 11. Create a program in which the Servo Robot picks parts from the Gravity Feeder and drop them in the metallic can. The process stops when the feeder is empty. Note: Do not forget to enable both the Robot and External Device check boxes to save the position of the Servo Robot and Linear Slide simultaneously. G 12. Execute your program. If it executes correctly, save it as EXE_10_A. 10-6

7 Figure Location of the equipment on the Work Surfaces. G 13. Once your experiment is completed, turn off the Robot Controller. Additional Experiment - Simulation of an Assembly and Transfer Process Program Description You will create a program in which a robot assembles parts. Once the assembly is completed, it is placed on a conveyor where it is transferred to another section of the production line. 10-7

8 You will use the Servo Robot, Gravity Feeder (Square Parts), Pneumatic Feeder (Cylindrical Parts), Rotary Carousel, Belt Conveyor, and Linear Slide. You will also use the two Delrin blocks, p/n , supplied with your system. The equipment will be placed as shown in Figure Do not place the equipment now. To do so, the Servo Robot picks a Delrin block from the Gravity Feeder and places it on the Rotary Carousel as shown in Figure Then the Rotary Carousel starts to rotate in the clockwise direction and continues to rotate until the Delrin block is detected by the limit switch. At this moment, the Servo Robot is moved using the Linear Slide to pick a cylindrical part from the Pneumatic Feeder. Figure Gripper placing a part on the platter of the Rotary Carousel. Then the Servo Robot moves back to the Rotary Carousel and places the cylindrical part into the bore of the Delrin block to complete the assembly. The Servo Robot picks the assembly and places it in the detection zone of the Belt Conveyor. Then the Belt Conveyor starts to move in the reverse direction and stops when the part is detected by the limit switch. The process repeats twice or stops if parts are missing in one the feeder. At the beginning of the program, Relays 1, 2 and 3 are set at low. The program also ensures that the Belt Conveyor is stopped and the direction is set at reverse. Messages and Warnings At the beginning of the execution, the program checks if there are parts on the Rotary Carousel and on the Belt Conveyor. If this is the case, the program displays one of the following messages "REMOVE THE PARTS FROM THE ROTARY CAROUSEL" or "REMOVE THE PARTS FROM THE BELT CONVEYOR", the LED of Relay 2 will light, and the program will wait for the parts to be removed before proceeding with the next instruction line. Before moving to pick a Delrin block from the Gravity Feeder, the system will check if the Gravity Feeder and the Pneumatic Feeder are not empty. If this is the case, the 10-8

9 program will display one of the following messages "FEED THE GRAVITY FEEDER" or "FEED THE PNEUMATIC FEEDER", the LED of Relay 3 will light, and the program will wait for the feeders to be fed before proceeding with the next instruction line. The LED of Relay 1 will light to indicate that the Servo Robot is moving. Program Flow Chart G 14. Draw a flow chart for this program in Figure Note: If necessary, refer to the Suggested Flow Chart (Figure D-3), Input/Output Connection Table (Table D-2), Suggested TTL Input/Output Connection Diagram (Figure D-4), Suggested Belt Conveyor Settings, and Suggested Program Listing shown in Appendix D. 10-9

10 Figure Flow chart for the assembly and transfer process program

11 TTL Input/Output Connection Table G 15. Complete the TTL input/output connection Table Gravity Feeder EXTERNAL DEVICES Pneumatic Feeder Rotary Carousel Belt Conveyor Limit Switch NO contact Limit Switch NC contact Limit Switch S2-B NO contact Limit Switch NO contact Limit Switch NC contact Limit Switch NO contact Limit Switch NC contact Stop Ext. Input Motor Ext. Input Direction Ext. Input TTL INPUT ROBOT CONTROLLER TTL OUTPUT Table TTL input/output connection table. TTL Input/Output Connection Diagram G 16. Complete the TTL input/output connection diagram of Figure G 17. Install the equipment as shown in Figure Note: If you do not have a Pneumatic Feeder (Cylindrical Parts), use the Pneumatic Feeder (Square Parts) and position the part on top of the Delrin block. G 18. Fill the Gravity Feeder with 2 Delrin blocks. Note: The Delrin blocks must be oriented the same way each time the program is executed. Note the orientation if necessary. G 19. Make the connections shown in Figure Note: Use the long leads of the Belt Conveyor to connect the Gravity Feeder to the Robot Controller

12 Figure TTL input/output connection diagram. G 20. On the control panel of the Belt Conveyor, set the controls as required by your program. Connect the Belt Conveyor to an AC power source. G 21. Turn on the Robot Controller and Belt Conveyor by setting their power switch at the I (on) position. G 22. Execute a hard home positioning. G 23. Use the Hand-Held Terminal to create the position points, and Robotics to create the task

13 Linear Slides Note: Do not forget to enable both the Robot and External Device check boxes to save the position of the Servo Robot, Rotary Carousel, and Linear Slide simultaneously. Pick the parts from the Pneumatic Feeder as shown in Figure Figure Servo Robot picking a part from a Pneumatic Feeder. G 24. Execute your program once. G 25. Does your program execute correctly? G Yes G No G 26. Test the execution of the program with and without parts in the Gravity Feeder, Pneumatic Feeder, Rotary Carousel, and Belt Conveyor. Note: You will have to execute the program many times to test all conditions and check if the messages appear correctly. Do the messages appear correctly? G Yes G No G 27. Do the LEDs light as defined in the program description? G Yes G No G 28. Once your program is completed, save it as EXE_10_B

14 Shutdown Procedure G 29. Make sure that there is nothing inside the gripper. G 30. Clear the area around the Servo Robot so that it will not hit anything when it moves. G 31. Execute a hard home positioning. G 32. Turn off the Robot Controller and Belt Conveyor by setting their power switch at the O (off) position. G 33. Disconnect the system and return the equipment to its storage location. CONCLUSION In this exercise, you were introduced to the use of a linear slide to extend the work envelope of a robot. You experimented with the use of the Message command to introduce messages and warnings during the execution of a program. You designed a flow chart, prepared a connection diagram, and created a program that simulates an assembly and transfer process. REVIEW QUESTIONS 1. What is the Linear Slide used for? 2. Explain why it is important to save the position of the Servo Robot and Linear Slide simultaneously

15 3. Name a parameter for which you must be very careful when using the Linear Slide. 4. Describe what will happen if the Simulation of an Assembly and Transfer Process program is launched without parts in the Gravity Feeder. 5. Describe will happen if the Simulation of an Assembly and Transfer Process program is launched with parts on the Belt Conveyor