cheezstix! ee 396 micromouse spring 2007 final presentation

CheezStix!CheezStix!

EE 396 MicromouseEE 396 Micromouse

Spring 2007Spring 2007

Final PresentationFinal Presentation

MembersMembers

Toy Lim – Project ManagerToy Lim – Project Manager Kyle Montpas – Software LeaderKyle Montpas – Software Leader Tyson Kikugawa – Hardware LeaderTyson Kikugawa – Hardware Leader

OverviewOverview

Design and build an autonomous robotic mouse Design and build an autonomous robotic mouse to find its way to the center of a maze as fast as to find its way to the center of a maze as fast as possiblepossible

System Block DiagramSystem Block Diagram

Rabbit Rabbit µµPPRCM 2020RCM 2020

DriveDrive

H-BridgeH-BridgeDriver ICDriver IC

BipolarBipolarMotorsMotors

FT232RLFT232RL

PCPC

USBUSBRS232RS232 RS232RS232EmulatorEmulatorDynamic CDynamic C

ProgrammingProgrammingCableCable

ACACAdapterAdapter

PowerPower

LiPoLiPoBatteriesBatteries

5V DC-DC5V DC-DCConverterConverter

Li+Li+ChargerCharger

SenseSense

SideSideSensorsSensors ADCADC

3.3V V3.3V VREFREF

CheezStix! CheezStix! µµMouseMouse

DriveDrive

Rabbit Rabbit µµPPRCM 2020RCM 2020

DriveDrive

H-BridgeH-BridgeDriver ICDriver IC

BipolarBipolarMotorsMotors

FT232RLFT232RL

PCPC

USBUSBRS232RS232 RS232RS232EmulatorEmulatorDynamic CDynamic C

ProgrammingProgrammingCableCable

ACACAdapterAdapter

PowerPower

LiPoLiPoBatteriesBatteries

5V DC-DC5V DC-DCConverterConverter

Li+Li+ChargerCharger

SenseSense

SideSideSensorsSensors ADCADC

3.3V V3.3V VREFREF

CheezStix! CheezStix! µµMouseMouse

DriveDrive

Opted for $250 budget over kitOpted for $250 budget over kit Design to be compact and lightDesign to be compact and light

Smaller stepper motor – 25.4mm x 38mm sq. Smaller stepper motor – 25.4mm x 38mm sq. (versus kit – 39mm x 42.3mm sq.)(versus kit – 39mm x 42.3mm sq.)

H-Bridge chip (SN754410)H-Bridge chip (SN754410)

DriveDrive

SensorSensor

Rabbit Rabbit µµPPRCM 2020RCM 2020

DriveDrive

H-BridgeH-BridgeDriver ICDriver IC

BipolarBipolarMotorsMotors

FT232RLFT232RL

PCPC

USBUSBRS232RS232 RS232RS232EmulatorEmulatorDynamic CDynamic C

ProgrammingProgrammingCableCable

ACACAdapterAdapter

PowerPower

LiPoLiPoBatteriesBatteries

5V DC-DC5V DC-DCConverterConverter

Li+Li+ChargerCharger

SenseSense

SideSideSensorsSensors ADCADC

3.3V V3.3V VREFREF

CheezStix! CheezStix! µµMouseMouse

SensorsSensors

Sharp Distance Sensor (GP2Y0A21YK)Sharp Distance Sensor (GP2Y0A21YK)

SensorSensor

Placement (Sides)Placement (Sides) Placed facing Placed facing

outward to shorten outward to shorten distance for more distance for more accurate readingaccurate reading

Angle to see into the Angle to see into the next cellnext cell

Adjusts to keep side Adjusts to keep side values equalvalues equal

30º 30º

SensorsSensors A/D Converter – MAX118A/D Converter – MAX118 Sensor output – analog (voltage), Sensor output – analog (voltage),

depending on distancedepending on distance Rabbit reads in digitalRabbit reads in digital Sensor --/--> RabbitSensor --/--> Rabbit

SensorsSensors

0

0.5

1

1.5

2

2.5

3

3.5

0 5 10 15 20 25 30

Distance (cm)

Vo

ltag

e

Voltage Reference chip – MAX6029Voltage Reference chip – MAX6029 Using 3.3V VREF+ for ADC since the max Using 3.3V VREF+ for ADC since the max

sensor output was found to be 3.12Vsensor output was found to be 3.12V

SensorSensor

PowerPower

Rabbit Rabbit µµPPRCM 2020RCM 2020

DriveDrive

H-BridgeH-BridgeDriver ICDriver IC

BipolarBipolarMotorsMotors

FT232RLFT232RL

PCPC

USBUSBRS232RS232 RS232RS232EmulatorEmulatorDynamic CDynamic C

ProgrammingProgrammingCableCable

ACACAdapterAdapter

PowerPower

LiPoLiPoBatteriesBatteries

5V DC-DC5V DC-DCConverterConverter

Li+Li+ChargerCharger

SenseSense

SideSideSensorsSensors ADCADC

3.3V V3.3V VREFREF

CheezStix! CheezStix! µµMouseMouse

PowerPower

Li-Ion BatteriesLi-Ion Batteries 3.7 Volt, 2 Amp-hour rating3.7 Volt, 2 Amp-hour rating

DC Converter – MAX1709DC Converter – MAX1709 Step up to 5 VoltsStep up to 5 Volts Can handle up to 4 A currentCan handle up to 4 A current

PowerPower

Added Design Feature - USBAdded Design Feature - USB

Rabbit Rabbit µµPPRCM 2020RCM 2020

DriveDrive

H-BridgeH-BridgeDriver ICDriver IC

BipolarBipolarMotorsMotors

FT232RLFT232RL

PCPC

USBUSBRS232RS232 RS232RS232EmulatorEmulatorDynamic CDynamic C

ProgrammingProgrammingCableCable

ACACAdapterAdapter

PowerPower

LiPoLiPoBatteriesBatteries

5V DC-DC5V DC-DCConverterConverter

Li+Li+ChargerCharger

SenseSense

SideSideSensorsSensors ADCADC

3.3V V3.3V VREFREF

CheezStix! CheezStix! µµMouseMouse

Added Design Feature - USBAdded Design Feature - USB

USB interfacingUSB interfacing Used in both power and control Used in both power and control

subsystemssubsystems Programming – FT232RProgramming – FT232R Battery Charging – MAX1811Battery Charging – MAX1811

Charge Current/Voltage SelectCharge Current/Voltage Select

Added Design Feature - USBAdded Design Feature - USB

Added Design Feature - USBAdded Design Feature - USB

PowerPower

ControlControl Rabbit 2000 microprocessorRabbit 2000 microprocessor

The PCBThe PCB

PCB over self wiringPCB over self wiring Cost moreCost more CleanerCleaner Less errorLess error

KiCADKiCAD Open-Source/FreeOpen-Source/Free 3D View3D View

The PCB - LayoutThe PCB - LayoutSilkScreeSilkScree

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The PCB - LayoutThe PCB - Layout

Top-ViewTop-View

The PCB - LayoutThe PCB - Layout

Bottom-ViewBottom-View

Physical LayoutPhysical Layout

FRONTFRONTSIDESIDE

Current IssuesCurrent Issues

Charger voltage source and current are Charger voltage source and current are manually selectedmanually selected Use 3-pin jumper between source connectorsUse 3-pin jumper between source connectors Use a charge current selection switchUse a charge current selection switch Maximum charger current is 500mAMaximum charger current is 500mA

PCBPCB LateLate Soldering small componentsSoldering small components

Future ImprovementsFuture Improvements

Add addition logic (transistors and diodes) Add addition logic (transistors and diodes) to the charger circuit to make it automatic, to the charger circuit to make it automatic, and increase charging currentand increase charging current

Improving the program…Improving the program… Store map of mazeStore map of maze Solve shortest pathSolve shortest path Etc.Etc.

Questions?Questions?

http://cheezstix.homeip.net

The PCB - LayoutThe PCB - Layout