[ekapalka]

Thanks I knew that, though. The reason I need to figure out the angle relative to the sides is so that I can calculate the reflection angle off of any one or two walls. I was hoping it could be done computationally using just rangefinders and not the servo or accelerometer, but I think that might take some experimentation to get right. I know it would be easy to do if the robot was always facing the same direction, but it could be facing any direction when it's near a wall. Thanks for your reply