Experimental evaluation of a new braking system for use in passive haptic displays

Abstract

Passive haptic displays have several advantages when compared to active devices. Safety elements associated with active haptic displays may make them undesirable for certain applications. One method of actuation for passive haptic robots is through the use of brakes and clutches. Traditionally, friction brakes have undesirable behaviour, such as stiction and delay in response time due to mechanical motion. In this study a new brake concept is proposed. The performance of this brake is evaluated and quantified through a series of controlled experiments. Particular attention is given to the phenomenon of stiction in Delrin, dynamic response of the new brake, and effectiveness of feedback control for braking torque.