R3R3 Ethan Hall Michael Kelton Greg Wegman Vashisht Lakhmani

PSSC An ability to receive and reply to movement commands from a wireless interface. An ability to drive and steer the vehicle using an interface. An ability to transmit video data from the vehicle to the user interface. An ability to autonomously navigate to a predetermined location using ultrasonic navigation. An ability to charge batteries using induction pads without direct user interaction.

Block Diagram

Outline Major Design Considerations Interface Requirements Computation Requirements On-Chip Peripherals Off-Chip Peripherals Power Constraints Packaging Constraints Cost Constraints Component Selection Location Detection

Major Design Constraints Power Draw Proper battery charging Longevity/sustainability Accurate location detection

Interface Requirements Connect to Computer/Tablet Control Angle of 4 drive motors Control Speed and Direction of the 4 motors Display LED information about current status of Rover Detect objects in direct path of rover Detect location in 'box'

Computational Requirements Gather sensor data Calculate positions Network communication Safe movement (not hitting anything)

On-Chip Peripheral Requirements I2C - Communicate to devices capable of I2C 4 Servo PWMs for motor steering 1 Servo PWM for camera control 2 PWM for motor speed control 10 GPIO (LEDs, Misc input) 2 UART (USB-Serial, Wifi) 6 ADC(6 IR Detectors) USB Serial

Off-Chip Peripheral Requirements Wifi H-Bridges for motors LED Drivers 4 ADC for Ultra-Sonic Range Detection Power supply and battery sensing

Power Constraints Requires batteries LiPoly batteries will be used for power density On board power supply for logic voltage levels

Packaging Constraints Look as close to Opportunity as possible Small form factor (RC car) Replaceable Battery Manual Charging (in error states) Light Weight

Cost Constraints Expensive Keep costs down to allow for multiple copies to be made. Applied for a grant to offload the cost from EPICS

Component Selection: Microcontroller LPC1768 ARM Cortex-M3 512KB flash 64KB SRAM 10/100 ethernet USB 2.0 Host/Device/OTG I2C 12-bit ADC Want to learn ARM Nice programming environment

Component Selection: Wifi WiFly GSX Breakout $84.95 UART/SPI with Wifi b/g compliant

Component Selection: Motor 298:1 Micro Metal Gearmotor $15.95 Metal gears provide longer life

Location Detection Ultra Sonic + Easy to use + Accurate + Easily available - Requires angle - Complex location detection RF + Able to create a hash map for distance + Scalable - Requires external devices - Requires external power supplies - Complicates changeable box