1. CheezStix! EE 396 Micromouse Spring 2007 Final Presentation

2. Members  Toy Lim – Project Manager  Kyle Montpas – Software Leader  Tyson Kikugawa – Hardware Leader

3. Overview  Design and build an autonomous robotic mouse to find its way to the center of a maze as fast as possible

4. System Block Diagram Rabbit µP RCM 2020 Drive H-Bridge Driver IC BipolarMotors FT232RL PC USBRS232RS232Emulator Dynamic C ProgrammingCable ACAdapter Power LiPoBatteries 5V DC-DC Converter Li+Charger Sense SideSensors ADC 3.3V V REF CheezStix! µMouse

5. Drive Rabbit µP RCM 2020 Drive H-Bridge Driver IC BipolarMotors FT232RL PC USBRS232RS232Emulator Dynamic C ProgrammingCable ACAdapter Power LiPoBatteries 5V DC-DC Converter Li+Charger Sense SideSensors ADC 3.3V V REF CheezStix! µMouse

6. Drive  Opted for $250 budget over kit  Design to be compact and light  Smaller stepper motor – 25.4mm x 38mm sq. (versus kit – 39mm x 42.3mm sq.)  H-Bridge chip (SN754410)

7. Drive

8. Sensor Rabbit µP RCM 2020 Drive H-Bridge Driver IC BipolarMotors FT232RL PC USBRS232RS232Emulator Dynamic C ProgrammingCable ACAdapter Power LiPoBatteries 5V DC-DC Converter Li+Charger Sense SideSensors ADC 3.3V V REF CheezStix! µMouse

9. Sensors  Sharp Distance Sensor (GP2Y0A21YK)

10. Sensor  Placement (Sides)  Placed facing outward to shorten distance for more accurate reading  Angle to see into the next cell  Adjusts to keep side values equal 30º

11. Sensors  A/D Converter – MAX118  Sensor output – analog (voltage), depending on distance  Rabbit reads in digital  Sensor --/--> Rabbit

12. Sensors  Voltage Reference chip – MAX6029  Using 3.3V VREF+ for ADC since the max sensor output was found to be 3.12V

13. Sensor

14. Power Rabbit µP RCM 2020 Drive H-Bridge Driver IC BipolarMotors FT232RL PC USBRS232RS232Emulator Dynamic C ProgrammingCable ACAdapter Power LiPoBatteries 5V DC-DC Converter Li+Charger Sense SideSensors ADC 3.3V V REF CheezStix! µMouse

15. Power  Li-Ion Batteries  3.7 Volt, 2 Amp-hour rating  DC Converter – MAX1709  Step up to 5 Volts  Can handle up to 4 A current

16. Power

17. Added Design Feature - USB Rabbit µP RCM 2020 Drive H-Bridge Driver IC BipolarMotors FT232RL PC USBRS232RS232Emulator Dynamic C ProgrammingCable ACAdapter Power LiPoBatteries 5V DC-DC Converter Li+Charger Sense SideSensors ADC 3.3V V REF CheezStix! µMouse

18. Added Design Feature - USB  USB interfacing  Used in both power and control subsystems  Programming – FT232R  Battery Charging – MAX1811  Charge Current/Voltage Select

19. Added Design Feature - USB

21. Power

22. Control  Rabbit 2000 microprocessor

23. The PCB  PCB over self wiring  Cost more  Cleaner  Less error  KiCAD  Open-Source/Free  3D View

24. The PCB - Layout SilkScree n

25. The PCB - Layout Top-View

26. Bottom-View

27. Physical Layout FRONTSIDE

28. Current Issues  Charger voltage source and current are manually selected  Use 3-pin jumper between source connectors  Use a charge current selection switch  Maximum charger current is 500mA  PCB  Late  Soldering small components

29. Future Improvements  Add addition logic (transistors and diodes) to the charger circuit to make it automatic, and increase charging current  Improving the program…  Store map of maze  Solve shortest path  Etc.

30. Questions? http://cheezstix.homeip.net

31. The PCB - Layout