Mechanical brake design for passive haptic device

This paper explores a new mechanical brake design to be used in order to limit the motion in low cost and high force passive haptic device design. The designed mechanical brake was inspired from the working principle of a coaster brake used in bicycles. The brake consists of conic surfaces actuated by a DC motor. A leaf spring is added to the system to detect the direction of the user movement. A 1-DOF haptic interface was developed to study virtual wall collisions. Two different prototypes were manufactured with different braking torque capacities. The second prototype is smaller and has a PID controller. The aim of this novel approach is to allow the user to move the haptic tool away from inside of the virtual wall without using torque sensor when full braking force applied. Experimental results showed that the mechanical brake can be a promising alternative as a brake mechanism for passive haptic device design.