[Andy A.]

It's as effective as the speed in which the motor is turning. As the motor gains speed it generates a higher voltage with slows it down. As it slows down, the voltage drops which lowers the effective braking effect so it speeds back up. This roller coaster gets averaged out of course, so in effect the brake produces a speed in which all the forces balance out.

As for keeping a robot on the ramp, it probably won't be enough. It will slow a robot down, but the robot will keep moving until the force of gravity can not overcome the friction of the drive train. Since scoring of objects on the ramp won't happen right away, the bot will probably hit the carpet before being scored.

The dynamic brake can slow down a motor. It can not 'lock up' a motor because as soon as the motor is not moving, it is not generating a voltage.

-Andy A.