Team GPS Rover Alex Waskiewicz Andrew Bousky Baird McKevitt Dan Regelson Zach Hornback

Overview Project Main Objectives Outline of Approach Implementation of Sub-Systems Division of Labor and Responsibilities Schedule Risks and Contingency Plan

PROJECT MAIN OBJECTIVES

Baseline Functional Description The human user will be able to drive the rover Rover will calculate its location and bearing Rover will transmit telemetry to the user The user will command the rover Rover will sense and avoid obstacles Rover will autonomously maneuver to its assigned destination

Extended Functional Description Rover could have onboard camera(s) providing visual feedback to user. Rover could be able to carry and deploy instrumentation packages – Rocket launch platform – Environmental sensors – Mechanical Manipulator

Drive

OUTLINE OF APPROACH

VEHICLE Traxxas Rustler – 445x311x178 mm – 1.69 kg – Top Speed 35 mph – $203 with batteries – High Load Capacity – Replaceable parts Electronics Platform – Attaches to the chassis – Carries electronics, sensors, and batteries – Interfaces directly with car controls – Weight and Size are constraints

ELECTRONICS GPS module Digital compass Proximity sensors RPM monitors Control block 2-way RF communication link Power system

Block Diagram Control Block Digital Compass GPS Module RF Link Proximity Sensors Wheel Encoders Motor Laptop PC

SOFTWARE Vehicle control GPS Interface Coordinate Tracking Pathfinding Collision Avoidance & Sensors Communication Possible Reprogramability – Preserve stop functionality & remote programming – Receiver Transmitter Pairs

IMPLEMENTATION OF SUB-SYSTEMS

GPS Parts Requires transmitter/receiver and interface board. EM406 SiRF III Evaluation Board - RS232 - $30 20 Channel EM-406 SiRF III Receiver with Antenna - $60 Concerns: Interfacing eval board with PC & resolution of GPS (10meters listed)

RF Link 4800bps UART Analog or digital modes $15 Variable range with transmitted voltage Sparkfun

Digital Compass $60 ½ degree resolution I 2 C interface Provides excellent tracking coordination with GPS sensor e/product_info.php?products_id=79 15

RPM Monitors Measure speed and distance traveled Along with Digital Compass provides backup and coordination with GPS tracking Buy or Build? Optical Encoder – Black and white “spokes” on inside of wheel

Programmable Logic Xilinx CPLD or FPGA to sample sensors and place sensor data in external memory May use extra logic to control motors if PWM block is inaccessible Sensor 3 Logic External RAM Microcontroller Sensor 2Sensor 1

Microcontroller Required – Dedicated data and address busses to external memory Wishlist: ability to “easily” interface with peripherals – Onboard ADC(s) – Onboard PWM – Onboard I 2 C module, or other serial communication protocol

Sensors Use: 2 sensors, one forward, one downward – Provides obstacle avoidance and drop-off detection Options: – Ultrasonic: Devantech SRF08 Ranger ($62) 6m range I 2 C interface – IR: Sharp GP2Y0A21YK ($12) 80cm range Analog interface Sensor configuration

Power Subsystem 2.5V, 3.3V, 5V systems (potentially) Use of two 9V batteries in parallel: – Won’t need more than 9V, will provide sufficient energy Use of 3 voltage regulators – Simple and cheap

DIVISION OF LABOR AND RESPONSIBILITIES

ALEX ANDREWBAIRDDANZACH Car Interface GPS CPLD Software Chassis Mount Perf Board RF Link Power Car Interface Chassis Mount Sensors Organize Documents Car Interface Power RPM Monitors Digital Compass GPS Sensors CPLD Digital Compass Software

SCHEDULE

Done In progress Not started

RISKS AND CONTINGENCY PLAN

Risks and Contingency Plans Parts availability and shipping times Cost Interfacing with the Car Providing sensor data to the microcontroller RF communication Component failure

Questions?