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
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
Required Components
Hardware:
- Servos
- Microcontroller (Parallax Basic Stamp BS2P40)
- PSC (Parallax Servo Controller)
- Parallax BOE (Board of Education)
Motherboard
- Color Sensor (TAOS TCS 230)
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)
Project Overview
Robot Arm
MICROCONTROLLER
MOTHERBOARD
PARALLAX SERVO
CONTROLLER
COLOR SENSOR
System Connections
Microcontroller
Interface to Color Sensor
(Level 4)
Interface with Servo
Controller
(Level 4)
Interface to
MOTHERBOARD
PARALLAX BOE
(Level 4)
Servos
Input and Output Diagram
Hierarchical Decomposition
Robot Arm
(Level 1)
Hardware Module
(Level 2)
Software Module
(Level 2)
HARDWARE MODULE
Hardware
Module
(Level 2)
Power
(Level 3)
User Interface
(Level 3)
Servo
Controller
(Level 3)
Microcontroller
(Level 3)
Servos
(Level 3)
Color Sensor
(Level 3)
Microcontroller
Motherboard
Parallax BOE
(Level 3)
User Interface
User Interface
(Level 3)
Microcontroller
Configurations (Level 4)
(Level 4)
Adjusting Servo Motor
Controller (Level 4)
Servo Module
Servo Motor Control
(Level 3)
Processor Interface to Servo Control Module
(Level 4)
Interface to Servos
(Level 5)
Servo to control pivoting arm, i.e. degree of
rotation
Servo to control the gripper, i.e. the
opening/closing of the clamp
Servo to control arm extension and contraction
Sensor Module
Reference: Internet, Datasheet Catalog, http://www.datasheetcatalog.org/datasheets2/10/103569_1.pdf
Software Module
Software
Functionalities
Basic Arm Movement
Pick Up and Place
Object
Color Sorting
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
SEGMENT A: BASIC ARM
MOVEMENT
Flowchart of Segment B – Pick Up and
Place Object
Start
Get the
program
and user
data from
the
software
Wait for storage
of arm joints to
be placed in
array.
Store arm joints
segments in the
form of an array in
the Parallax
BS2P40 EEPROM
User calls each
joint of the arm
using IF
statements and
by applying
bitenable = 1
Arm movement is initiated
accordingly.
End Process
Start
SEGMENT C: COLOR
SORTING
User downloads
correct and debugged
code to
microcontroller
1st Section of Code is
executed: Take action if
right color is found
Store Color
Values into
EEPRROM
Red?
Green?
Blue?
Yellow?
Place colored object
directly to appropriate
box
IF
Red? Green? Blue?
Yellow?
Place arm and joints
back to collecting
position.
Execute 2nd section of
code: Test for color of
object.
Match color
values from
EEPROM
Initiate arm joint movement
IF no block?
End Process
Call the same
procedure to place
object into
appropriate box
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.
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.
Quantum VGM Software Used to test color
sensor value readings
Reference: Quantum Data,
http://www.quantumdata.co
m/pdf/CS-1Quik.pdf
CIE Color Chart for color matching
Reference, Internet, Photonet,
http://photo.net/photo/edscott/vis00020.h
tm
Example: The RGB value of 0.6 and 0.4
represents red.
2nd Software used to test color sensor:
TCS3414EVM
Test results
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
Some Completed Pictures of the Robot
Arm
Side View
Close Up View of Color Sensor
Top Level View
Gantt Chart Showing the timeline from
initial research to the completion of
Robot Development
Labor Costs Graph
Estimated, Actual & Projected Cumulative Expenditures (in $k)
$140.00
$120.00
$100.00
$80.00
$k
Estimated
Projected
Actual
$60.00
$40.00
$20.00
$0.00
0
5
10
15
20
Time From ROC (in Weeks)
25
30
35
THE END
THANK YOU!