We are using the line sensors. Originally we were using PID control with encoders and limit switches but we were having problems on Saturday, as referenced here:
http://www.chiefdelphi.com/forums/sh...78#post1023378
So we went to just running each linkage for a certain period of time and that is working very consistently, thanks to the window motors backlash. We are using 4 window motors (2L and 2R), 2 for our arm joint, 1 for our wrist joint and 1 for the winch that opens/closes the gripper. If we had chosen to use any other motor for any of these motions this might not have worked. The backlash saved us
We were planning on using the camera and had gone through some pretty extensive testing with our vision processing but we realized that with our gripper design there would be no way to see the peg cap with a tube on board where it would definitely help. We could see the peg cap from the robot frame with the camera, but in order for it to be a viable solution it had to be on our arm. So instead we mounted our camera in reverse to aid with alignment of the minibot tower.