Abstract
It is proposed that a new brake device which enable to control the braking force using piezo actuator. In this method, a friction plate is vibrated in the direction of slipping and then velocity of the friction plate should be set up so as to have the time period wherein it exceeds velocity of a rotating disk. By changing this time period, average braking force can be controlled. This method isn't affected by displacement of contact place of a friction pad due to wear, therefore it ensures long term stable control of braking force. It has been experimentally confirmed that this method is available for controlling braking force.
