Encoder for Crab Steering

[Alphabet OJ]

Hello!

We have built a crab-drive robot for this year (2009) and we need a sensor to find where the wheels are facing to use in the program.

We are pretty sure we are going to use a 270 degree potentiometer, but we want to look at an encoder because it will be easier to mount.


We would use the kit-of-parts encoder, so it is not absolute like a potentiometer would be. The program would need to remember that "we are 10 ticks to the right of center" and stuff like that, and we would need to start the robot with the wheels strait forward every competition. We also are worried that it would "forget" its position after autonomous. For example, if we steered 10 clicks past center to the right in autonomous and then we changed to teleoperated, could the code remember where the wheels were? Or is the memory cleared at the end of autonomous?

Any help would be great! If anyone has used encoders for crab steering before or something like that, we'd love to hear from you. Thanks!