Offboard coprocessor!

[Doug G]

Originally Posted by ericand

Team 1425 uses a PIC processor to controll the speed of the ball shooter this year. The shooter has two impeller wheels that give the ball its velocity. Our aiming depends on the shooter having a constant velocity as close to the limit as possible.

The PIC processor uses digital I/O to provide 2 bits of info for each impeller. The code on the robot controller uses 3 of the 4 possible
combinations to tell if the impeller is {too slow, on speed, too fast}

The robot controller uses this info to determine if/how to adjust the PWMs controlling the impeller motors.

We do the same thing with our shooter, but just simply use a couple of encoders connected to the RC and Watson's velocity PID code with some tweaking of the constants and are getting pretty good results. So why use the separate PIC?