GPS Rover

Travis Gruber

Phil Treddenick

Matt Kennedy

Marcin Skirucha

Overview

• Rover Features• Overall System Block Diagram• Parts Listing• Peripherals • System Board • Software• Schedule• Division of Labor

Rover Features

• User Friendly GUI• On-The-Fly Waypoint

Selection • Remote Shutdown• Multi-Speed Selection• Integrated Collision &

Inclination Detection• Waypoint Backtracking

upon collision

System Block Diagram

ADC

ADC

68HC11

A/D

Various IO Pins

RS232

SystemMemory

GPS

Digital Compass

Inclinometer

RF receiver

DAC

DAC

Drive Servo

MotorServo

Terminal

RF transmitter

Collision detectors

RS232Time/DivMux

RS232

Parts Listing

Peripherals

Traxxas RC Car BodyFutaba Remote and Servos

Trimble AgGPS 124/132 LocatorDigital CompassT2 Inclinometer

8.2 V NiCad Battery Pack8.2V NiCad battery for embedded board

Limit SwitchSerial RF Receiver/Transmitter

Digital Camera

System Board Components

MC68HC11 MCUEPROMSRAM

Xilinkx FPGAJtag interface

Bidirectional TransceiverTransparent Latches

5V Voltage RegulatorSPDT Reset Switch

Maxim RS232 DriverSiPs

DACs, ADCsVarious TTL logic

Peripherals – Rover Chassis

• Fiber Composite Chassis

• High Torque 20-Turn Motor

• Rotary 3-Speed Control

• 12.25” Front and Rear Track

• Adjustable Gear Ratio

• Steering Servo– 3.2kg-cm Torque

– 0.223sec/60 degree

Peripherals – Servo Interface

Universal

Servo Param’s

Vbat =8.2V

Vpower =6.2V

fservo =52.08Hz

pservo =20ms

Vp-p =5.7V

Steering Servo Duty

CyclesDneutral =8.2%

Dleft-MAX =10.4%

Dright-MAX =5.9%

Drive Servo DutyCycles

Dneutral =7.8%DMAX =10.4%DMIN =5.7%

Peripherals - GPS

• Trimble AgGPS 124/132– Receiver Specs:

• Size: 14.5cm W * 5.1cm H * 19.5cm D

• Weight: 0.76 Kk (1.68lb)

• Power: 7 Watts (max), 10-32V DC

– Antenna Specs• Size: 15.5 cm D * 14cm H

• Weight: 0.55Kg (1.2lb)

Peripherals – GPS Channels

• General– 12-channel, parallel tracking L1 C/A code and carrier phase filtered

measurements and multi-bit digitizer• Update Rate

– 1 Hz standard; 10Hz optional• Differential Speed Accuracy

– 0.1MPH (0.16KPH)• Differential Position Accuracy

– Less than 1 meter horizontal RMS; At least 5 Satellites, PDOP < 4 and RTCM SC-104 standard format broadcast form Trimble 4000RSI or equivalent reference station

• Time to first Fix– < 30sec (typical)

• NMEA Messages– ALM, GGA, GGL, GSA, GSV, MSS, RMC, VTG, ZDA

Peripherals – Limit Switch

• 2XC12 Enclosed Snap Action Limit Switch– Actuator Short Roller

– Size• 0.69in D * 0.95in H * 1.94in L

– Max Pretravel• 0.106in

– Overtravel• 0.064in

– Operating Force• 8.8-12.3oz

Peripherals - Inclinometer

• T2 Incremental Inclinometer– 2-channel quadrature outputs

– 3rd channel index option

– TTL compatible

– -40 to +100°C operating temperature

– Single +5V supply

– 360° range

– 3600 codes/rev. (900 CPR) = 0.1° resolution

Inclinometer Timing Diagram

Peripherals – Digital Compass

• 1490 Digital Compass– Power

• 5-18 volts DC @ 30 ma – Outputs

• Open collector NPN, sink 25 ma per direction– Weight

• 2.25 grams– Size

• 12.7 mm diameter, 16 mm tall– Pins

• 3 pins on 4 sides on .050 centers– Temp

• -20 to +85 degrees C

Quatech QTM-8524 RF Transceiver

• Power– 10-30 volts DC

• Features– Up to 500 m range with

open line of sight

– Supports baud rates from 600bps-57.6kbps

– Supports RS-232• Has TxD and RxD pins

– Requires external antenna, also provided by Quatech

Digital Camera

• KB Gear Jamcam V 3.0

• System Specs– 640 X 480 Max Resolution

– Serial Output with RS-232 Communications

– Stores up to 8 photos at 640 X 480 and 28 photos at 320 X 240

System Schematics

• Microcontroller

System Schematics

• Bus Drivers

System Schematics

• FPGA and EPROM

Memory Map

• 64 byte Register Block moved to 0000h

• 512 byte Internal RAM moved to 7000h

• External NVRAM mapped to 5000h

• EEPROM removed from B600h

• Memory Mapped IO at 1000h to 4FFFh

Current Status

• Successful Program Fetch and Execution– NOP NOP NOP JMP

• Integrated Xilinx FPGA– Debugging various chip selects

• Boot Monitor

Software Diagram

text

GPS

DigitalCom pass

Inclinom eter

Servos

SerialHandler

HeadingDeterm ination

S lope AngleDeterm ination

ServoControl

Inform ationDecode

SerialHandler

Com m andDecode

RFReceiver

RFTransm itter

Com m and GUIon W orkstation

MAINCONTROL

S oftware R unn ingon 68H C 11

Cam eraCam era

Com m unication

Workstation Software

RFTransm itter

Serial Connectoron W orkstation

File System onW orkstation

Serial Com m andEncoder and Handler

Location DataStorage

GUI

S oftware R unn ingon W orksta tion

Workstation GUI

• Send kill command• View current

waypoints• Set new waypoints• Store waypoint history• View waypoint history

Schedule Update

Division of Labor

• Matt– Finishing Board

– GPS Communications

• Marcin– Finishing Board

– Inclinometer

– Digital Compass

– Camera

• Travis– RF Communications

– Limit Switch

• Phil– Servo control

implementation

– GUI Interface

Conclusions

• Choices about Peripherals

• Progress so far

• Places where we anticipate the most difficulty

• Any Questions?