A Bluetooth enabled A Bluetooth enabled mobile robotmobile robot

Rory McGrath05000874

Final Year PresentationFinal Year Presentation

IndexIndexIntroductionTechnology BackgroundSystem Design And OperationConclusions

IntroductionIntroductionDesign a Bluetooth enabled mobile

robot Controllable via a wireless Bluetooth PC

based GUI.Port a control application to a mobile

handset. Develop a swarm of collaborative

robots. Develop software to show collaborative

tasks.

Technology BackgroundTechnology Background

BluetoothJava / J2MEPythonLinuxDuty CycleOpto-IsolatorsGumstix

Bluetooth Low power wireless

connectionsFrequency band of 2.45

gigahertz InexpensiveNot “line of sight”

technology“One to many

technology”Personal-Area Network.Avoid Disruptions by

“hopping”.

Bluetooth RFCOMMProtocol available for BluetoothCable replacement protocolCreates a virtual serial data

streamData stream is simple and

reliableApplications that used a serial

port can be easily and quickly ported to use RFCOMM.

Java J2MEJava is used to

provide applications for customer’s devices.

J2ME is a Java platform designed for mobile phones

Services are easily portable between different profiles and configurations

PythonAn interpreted object orientation

languageNo cross compiling to be done.Available for all major operating

systems.Network programming in Python is

simpler than other languages, i.e. C.

LinuxPopular open source computer

software environment that competes with Microsoft Windows

There are four main parts to Linux.◦The kernel◦Supplied programs◦The shell◦X

Duty Cycle

D = τ / T ◦τ Defined as the Time that the

function is not zero;◦T Defined as the period of the

function.

Opto-Isolators

Light emitting and sensitive device

Connect high and low power components with no risk of surges or spikes.

Gumstixconnex 400xm

bt400MHz (Intel

Xscale PXA255)16MB flash

memoryBluetooth

wireless connectivity

System Design & Operation

Hardware◦ Motors◦ Gumstix Circuit◦ Power Circuit◦ Gumstix Power Circuit◦ Ultrasonic

Software◦ Gumstix Server◦ PC Client◦ Phone Client

MotorsTwo 'Parallax' continous rotation5 volts on the red wire0 volts on the black wirePWM signal with a 0.75 to 2.25ms

width and a period of 18ms on the white wire

Gumstix CircuitProtect from 'surges'3V PWM from

Gumstix4V to activate 4N25

chip. Inverters used to

increase PWM to 5V

Power Circuit10V split

between 2 motors

9V for each inverter

Gumstix Power CircuitDesigned to isolate the Gumstix

from the other componentsPowers the Gumstix and safely

connects the two PWM signals and ground to the other circuits.

Powers the Gumstix with 6V

UltrasonicWas to be used

as a locating capability in a swarm

Both infrared and ultra sonic would be required

SoftwarePxaregs

◦Written in C◦Allows python to access Gumstix GPIO

pins. PyBluez

◦Python wrapper for Bluetooth resources.◦Manually add 'bluetooth.py' &

'bluetooth.so' ControlMotors

◦Written in Python◦7 Functions that control the motors

Gumstix Server

PC Client

Phone Client

Problems EcounteredTesting the opto isolator circuit.

Segmentation faults'burning out' of a GumstixReplacing a Gumstix.

ConclusionsA successful Bluetooth enabled mobile

robot was created.The robot can be controlled by a PC GUIControl was ported to a mobile deviceWith more Bluetooth Gumstix a robot

swarm could be achieved.◦ Build Ultrasonic transmitter and reciever◦ Create an algorithm to control ultrasonic◦ Addition to Server to connect to other

clients

Questions?