Final Presentation Micromouse Spring 08

8” Comb.

Group Member Roles Chris – Programming/Circuit Construction Joon – Circuit Construction/Programming Steve – Debugging

Primary: Build an autonomous robot that can find the center of a maze of set size. Secondary: Utilize the shortest path to travel to the center. Objectives

Our Initial Goals To find the center of a 16x16 maze and the shortest path to the center To apply our acquired engineering knowledge to this project To gain experience working as a team To follow our schedule To make new friends (on the Mainland)

Overview of Parts Side Sensors Rabbit Two Li-ion Rechargeable Batteries Chassis (sheet metal) MC3479 Stepper Motor Driver MAX118 A/D Converter Jameco Bipolar Stepper Motor 12VDC

Block Diagram (Circuit)

Block Diagram (Software)

Sensors + Wheels

Bottom Layer

Features Side sensor design (4) Two wheeled mouse Circuit construction by etching rather than free wires (Printed Circuit Board) Sliders on the bottom of our chassis for balance 16V source (two batteries)

Initial Design Printed Circuit Board (PCB) Top Portion

Back Portion

New PCB Design

Problems Wiring on PCB was too thin –Could not handle current that ran through 16V lines and some wiring came loose from the board Some chips did not work properly –ADC gave 4 outputs rather than 8 outputs (4 Most Significant Bits) –Soldered in a defective motor driver to PCB (worked when we tested it)

More Problems Rabbit –Wired Rabbit up incorrectly Mixed up ports –Blew out Rabbit

Resulting Changes PCB Board –Soldered wires in parallel to wires connected to 16V lines and ground ADC –Took the 4 outputs and disregarded the rest (The MSBs became our LSBs) Motor Driver –Used our spare PCB –Tested all motor drivers to see which worked Rabbit –Wired to correct ports

Future Improvements/Suggestions Use chip holders instead of soldering chips straight into the board Make thicker wires on PCB Check to see if all chips get the right amount of voltages (Be more careful)

Questions?