[ace123]

The best way to do this would be to hack up RoboEmu to calculate the angle and position based on the speed of the robot.

A really good way to do it would be to take a CAD model of your robot, hook it up into a 3d engine and allow the tetras to be separate objects. Then, make your robot's position be affected by PWM motor values (add a randomness and non-linear factor too). This project is definitely possible, and really isn't too hard, assuming you have the time to take all these different engines and attach them together.

Aside from this, there isn't any easier way to do it without cheating by using a 2d-model, and hard-coding arm positions for picking up tetras.

Just determining field positions (no arms or tetras) is really easy, and I was planning on doing that (change angle by difference of motor speeds, set velocity to motor speeds, ramping up velocity based on the pwm value), except I didn't know QT too well, and especially not the drawing part of it.