With this test rig, I plan to write a sketch for grisbot that will cause the robot to follow a flashlight beam. There will be two states, Triggered and Non-triggered. The transition to from N to T occurs at a value of 500 on the analog input port, while the transition from T to N occurs at 250.

The user will hold a flashlight up to grisbot, and if the value exceeds 500, the robot will do a brief 1/4 sec sweep side to side, then head toward the direction that has the maximum value of light. Every couple of seconds, the robot stops and does another sweep, then re-orients. This continues so long as the value remains above 250. If the value falls below 250, the robot enters the N state and stops. Every ten seconds, however, it will conduct a full circle sweep, and if it finds a value above 500, it will enter the T state and head off in the direction of maximum light.

Actually, that’s one possible mode of operation. I’m thinking of a couple more. I hope to fit them all in the same sketch with the path programs, so that everything can be activated via screen flash.