1. Team 6 Milestone 3 ● Matt Bouchard, Paras Metha, Andrew Butcher

2. Overview ● What We Will Talk About – Light Sensor Configuration – Electrical physical set-up – Line following changes – Battery – Bumper – Buzzer – Results – Future ● What We Won’t Talk About – Specific tasks ● Most approaches were ● similar

3. Light Sensor Configuration ● Three sensors, angled instead of parallel ● 15cm high, 13.5º spread of sensors ● Allows a larger field of view when detecting whether lights are on or off

4. Physical Setup of Electrical Components ● Too many uninsulated wires ● Too great a chance of short circuit at LED level Bender: Milestone 2

5. Physical Setup of Electrical Components ● Less chance of short circuit ● Easier placement of sensors ● Easier connection of large number of sensors (seven) ● Fun-tac used to hold sensors in housing

6. Battery Problem ● Four days lost because of intermittent resetting of the NMI board ● Slow-blow fuse partially blown ● Code that left values on the stack ● “Cooked” battery ● All lead to problems that reset the board

7. Bumper ● Originally mounted too low ● Required due to missing mounting bracket ● Supported by a loose wooden block

8. Buzzer ● Problems connecting the buzzer – DDRD must be set (so that Port D pins are appropriately used for output) – Port D pins 0 and 1 are used for the serial port – Thanks to the Dogs Of Thunder for supplying the transistor and the know- how.

9. Code ● State based ● Required meeting one task before the next could begin ● Unable to recover from errors ● Loop { – On Marker ● Enter State ● Perform “canned” series of movements ● Change state to reflect completion ● }

10. Failure…? ● Completed one full lap of the track during the first part of evaluation ● In point-based test, failed to complete one lap, leaving us in last place (300 points) ● Uncertain why system suddenly failed – Happened twice in the same place, gives us something to look into ● Lesson: – Expect it to happen from time to time – Build system robust enough to deal with such errors and continue

11. Future Plans ● Analog multiplexer – Many sensors are currently being used – Only one port E pin remaining ● Rewiring – Simplify wiring setup ● Rethink Benders Design – Too much “just make it work” due to time constraints

12. Future Plans ● Robust Code – As suggested by Chris Parker ● “Luxuries” – Items not yet implemented that would have been if more time had been available – Reset Switch – Motor/Sensor power switch – Missile Launcher