1. Senior Computer Engineering Project
THE GEORGE WASHINGTON UNIVERSITY School of Engineering and Applied Science Department of Electrical and Computer Engineering
FINAL PRODUCT REVIEW By
Syed Al Mohaymen
ECE 158
Senior Computer Engineering Project
April 20, 2009

2. Design Features
Robot arm capable of sorting colored blocks and placing them in color labeled bins
Features include:
Servo controller
Servos
Microcontroller Operations
Blocksorting Program Algorithm

3. Required Components Hardware: Servos
Microcontroller (Parallax Basic Stamp BS2P40)
PSC (Parallax Servo Controller)
Parallax BOE (Board of Education) Motherboard
Color Sensor (TAOS TCS 230)

4. Required Components Software: BASIC Stamp Editor 2.4
Parallax Servo Controller Interface (PSCI)
FTDI Driver (for USB connection establishment between the BOE Motherboard and PC)

5. PARALLAX SERVO CONTROLLER
Project Overview
Robot Arm
MICROCONTROLLER
MOTHERBOARD
COLOR SENSOR
PARALLAX SERVO CONTROLLER

6. System Connections Servos Microcontroller
Interface with Servo Controller
(Level 4)
Interface to MOTHERBOARD
PARALLAX BOE
Interface to Color Sensor
Servos

7. Input and Output Diagram

9. Hierarchical Decomposition

10. HARDWARE MODULE

11. User Interface

12. Servo Module

13. Sensor Module
Reference: Internet, Datasheet Catalog,

14. Software Module

15. BASIC Coding
There are three basic code segments (modules) shown below -
Segment A: Basic Arm Movement
Segment B: Pick Up and Place Object 
Segment C: Color Sorting

16. SEGMENT A: BASIC ARM MOVEMENT

17. Flowchart of Segment B – Pick Up and Place Object
Start
Get the program and user data from the software
Store arm joints segments in the form of an array in the Parallax BS2P40 EEPROM
Wait for storage of arm joints to be placed in array.
User calls each joint of the arm using IF statements and by applying bitenable = 1
Arm movement is initiated accordingly.
End Process

18. SEGMENT C: COLOR SORTING
Start
User downloads correct and debugged code to microcontroller
1st Section of Code is executed: Take action if right color is found
Red?
Green?
Blue?
Yellow?
Place colored object directly to appropriate box
Store Color Values into EEPRROM
Execute 2nd section of code: Test for color of object. IF
Red? Green? Blue? Yellow?
Match color values from EEPROM
Call the same procedure to place object into appropriate box
Initiate arm joint movement
Place arm and joints back to collecting position.
End Process
IF no block?
SEGMENT C: COLOR SORTING

19. Testing Software Module:
Step 1 – Write out code for basic arm movements and arm alignment. Run the code and see if it compiles.
Step 2 – Incorporate previously written code into complex “block sorting” code. Note this is the code which controls the robot arm for the required task. Using restricted robot arm basic movements from previous code, test the code and see if it compiles.

20. Testing (continued) Color Sensor Module:
Step 1: Place different colored objects in front of the sensor, vary the reading distance. Use: 5 inches, 8 inches and 10 inches respectively to see if the sensor can produce accurate RGB color values.
Step 2: Use the GUI software which came with the TAOS TCS230 color sensor package to read out the appropriate color values and record it.

21. Quantum VGM Software Used to test color sensor value readings
Reference: Quantum Data,

22. CIE Color Chart for color matching
Reference, Internet, Photonet,
Example: The RGB value of 0.6 and 0.4 represents red.

23. 2nd Software used to test color sensor: TCS3414EVM

24. Test results

25. Completed Work Completed the entire assembly of the robot arm
Tested all modules
Debugged and tested all code to ensure it is absolutely error free
Checked robot movement to see if it performs within given arm joint movement values
Over 1000 lines of coding and debugging
Approximately 840 hours of work

26. Some Completed Pictures of the Robot Arm

27. Side View

28. Close Up View of Color Sensor

29. Top Level View

30. Gantt Chart Showing the timeline from initial research to the completion of Robot Development

31. Labor Costs Graph

32. THE END THANK YOU!