Oh, duh!
If you really want to limit acceleration, you can use the accelerometers built into the RoboRIO; just select the one oriented along the axis that you're driving, or a vector sum of them that points you that way. For example, if your RIO is laid out on a board 30 degrees from horizontal, with the USB end towards the front and elevated, your acceleration in the drive direction would be
Code:
driveAccel = accelYaxis.getAcceleration() * .866 + accelZaxis.getAcceleration() * 0.5;