Roadmap to Mouse

Just a quick post to set my goals going forward.  Ordered and received my latest set of parts.  Got 2 18F2455 Pics.  Gpsim doesn't fully support them yet.  That will make starting out with them tough.  In the meantime, I played around with PWM operation of motors with the 16F876a.  Got A/D reads working with the phototransistors.

My next goal is to create a wall following robot with the 16F876a, using one Sharp IR sensor and PID control of the motors with PWM.  Really, it will only be PD control.  I won't need the Integral component for flat surfaces.

Once I get that working, I'll move on to a line follower.  I'll use the 16F876a and 5 IR sensors.  I'm thinking I'll use all 5 A/D pins.  I don't want to try receiving all 5 on the same A/D pin and lighting up each IR LED in turn.  Michah Carrick seems to have made this work, but it seems too likely to create interference.  I'll take a read of one phototransistor dark and then light up all five IR LEDs and take a read.  Then jump to the next phototransistor.

If all goes well, I'll start the first prototype of the mouse.  I am still thinking of using 3 Sharp sensors for alignment.  I'd really like to get a compass module and use that for alignment as well.  Maybe someday.

The biggest question right now is what to use for the base of the robot.  I'd like to get some Sintra or other plastic to work with.  I'm not overly confident in my craftsmanship with plastics though.

Got some Pololu micrometal gear motors with 30:1 ratio and some 42mm diam. wheels.  440 RPMs at 6V.  Should be close to 1m/sec with no load.  What blew me away was how small the motor and gear were!  Take a look: