Wheelchair Navigation Aid Technical Content Review By Rob Riel

Overview Planned Workflow Top Level System Design Hardware Design Software Design Mechanical Design

Planned Workflow Design hardware devboard, use for testing, work out any gremlins Re-spin devboard once for connectors for final product Develop Software after dev board obtained Hardware Design Software Design Debug Hardware

Top Level System Design System processes data from range finding sensors User is alerted visually and via sound of object encroachment. Product contains LCD screen which displays useful information Product also lights path of wheelchair with high power LED lighting

Top Level Design cont.

Hardware Design Hardware incorporates proven design practices such as: – UART-> FTDI -> USB Total board breakout connectors for access to all pins. (great for debugging and development) Stable 8Mhz operation Over engineered power traces to prevent burnouts Onboard Temp monitoring

Hardware Design cont.

Hardware Layout

Rendered Product Electronics

Software Design Software incorporates maximum efficiency by using: ISRs whenever possible Lightweight LCD drivers designed in house DSP instructions which take 1 clk vs normal 4 clks. Because drivers are designed in house complete control is maintained over data flow, decreasing time to market due to debugging

Overall Code Diagram Run Time Routines and Data Processing System And Peripheral Setup Variable And Structure Definitions

Variable and Structures Define Loop Vars Define Constants Define Macros For Screen Define Sensor Struct Define Screen Struct Define UART Struct

System and Peripheral Setup Setup Oscillator Setup Watchdog Setup Pin State (TRIS) Set Initial Pin Output Setup ADC Regs Setup Interrupts Setup UART Init Regs Initialize Screen

Run Time Routines & Data Processing Fetch & Store Sensor Data Compare Sensor Data to Thresholds Update Screen ISR For Change Mode ISR For Sending Data Via UART Update State Machine, Store to Screen Structure Calculate Bat Remaining

Mechanical Design Control Box

Mech Design LCD Box

Schedule