THE GEORGE WASHINGTON UNIVERSITY

School of Engineering and Applied ScienceDepartment of Electrical and Computer Engineering

FINAL PRODUCT REVIEWBy

Syed Al Mohaymen

ECE 158Senior 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 COLOR SENSOR

PARALLAX SERVO CONTROLLER

System Connections

Microcontroller Interface with Servo Controller(Level 4)

Interface to MOTHERBOARDPARALLAX BOE

(Level 4)

Interface to Color Sensor(Level 4)

ServosServos

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)

Servo Controller(Level 3)

Microcontroller(Level 3)

User Interface(Level 3)

Servos(Level 3)

Microcontroller MotherboardParallax BOE

(Level 3)

Color Sensor(Level 3)

User Interface

User Interface(Level 3)

Microcontroller Configurations (Level 4)

(Level 4)

Adjusting Servo Motor Controller (Level 4)

Servo ModuleServo 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 arm extension and contraction

Servo to control the gripper, i.e. the opening/closing of the clamp

Sensor Module

Reference: Internet, Datasheet Catalog, http://www.datasheetcatalog.org/datasheets2/10/103569_1.pdf

Software Module

Software Functionalities

Basic Arm MovementPick Up and Place

ObjectColor 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

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

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.

IFRed? 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

TestingSoftware 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.com/pdf/CS-1Quik.pdf

CIE Color Chart for color matchingReference, Internet, Photonet, http://photo.net/photo/edscott/vis00020.htm

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)

$0.00

$20.00

$40.00

$60.00

$80.00

$100.00

$120.00

$140.00

0 5 10 15 20 25 30 35

Time From ROC (in Weeks)

$k

Estimated

Projected

Actual

THE END

THANK YOU!