Micromouse 296 By Lemmings

Introductions  Vicky- coordinator, software oriented  Bryce-morale booster, software oriented  Ruffer-time keeper, hardware oriented  Sean-rule enforcer, hardware oriented

Overview  Make a robotic mouse as a group  Be able to find the center of a maze as fast as possible  Do so without crashing into a wall

Initial Goals  Map the maze using intersection markers –Use reverse directions to return to start –Coordinates prevent looping –Mark dead ends to prevent re-entry  Do a left wall hugger  Time permitting add other maze solving algorithms  Make the mouse move and turn  Find the center of the maze

Overall Design  Top Down Sensors  Using a Wall Hugger as the maze solver  Research previous micromouse projects in aid for design  Adjustable front sensor to fine tune centering in cells

Overall Design  13 sensors, 3 in each corner of the main board and one on the front  Large heat sink to prevent overheating that also has aesthetic purposes  Hid sensor circuit under a layer with the motor circuit

Accomplishments Thus Far…  Built the complete structure of our mouse  Built website  Programmed to hug the left wall  Learned to work more efficiently as a team  Center can be identified if found  Learned how to solder properly

Fixed Problems  Original chassis was too big –Built a new chassis  Couldn’t find 100 Ohm resistors for detector circuit –Used two 48 Ohm resistors in series  Difficulty tracking –One wheel moves twice as fast as the other –When too far off track back the other way –Limit the amount of tracking –Removed tracking directly after turning

Fixed Problems  Burnt out a MOSFET –Replaced the MOSFET and used a heat sink  Multiple sensor problems –Solder touching the chassis –Disconnected wires  Main board was crooked –Drilled larger holes for adjustability

Fixed Problems  Head portion had to be adjusted after changing designs –Support bars were re-cut to allow the head to move farther back  Inverter pins were incorrect –Looked up the correct pin placement and re-soldered

Fixed Problems  Not enough experience with tools –Learned how to use them  Sheet metal was thick and hard to mold –Made most of our chassis out of L-brackets  Main board was too low and touched the wheels –Cut holes into main board for wheels

Outstanding Problems  Make a seeking program that finds the center  Make a mapping program  Some wires are too long  Some components are loose  Mouse gets stuck on sliders  Sensors too sensitive

Suggestions  Increase the spacing between sensors horizontally  Decrease the spacing between sensors vertically  Use PC board with copper rings to make soldering easier  Some of the programming cables are less than reliable  Better equipment/tools would be helpful

We learned...  The lower the resistance, the higher the sensitivity of the sensors  Time management  How to work efficiently as a team  The proper way to solder  How to program the rabbit with stepper motors

We also learned...  Better ways to debug circuits  Better ways to program with C  How to use AutoCAD  MOSFETS and other components are heat sensitive  How to build a working heat sink  How to build a webpage

Website