November 2000 Symposium on Haptic Interfaces for Teleoperation and Virtual Reality, Asme International Congress and a High-bandwidth Force-controlled Haptic Interface

The design and control of a 5 degree-of-freedom (DOF) haptic interface that provides accurate rendering of forces as well as a large range of motion is presented. We review a number of design approaches that have been considered in other haptic interfaces and the reasons for choosing a parallel mechanism for our design. The choice and motivation for the actuators, sensors, and materials used are also discussed. High bandwidth transmission of forces is achieved through a force control loop in each degree of freedom. Details of the single actuator control design process and the robustness of the controllers are also overviewed. The resulting interface is able to provide a workspace of about 40 cm in translation in 3 DOF and about 60 degrees in 2 DOF of angular motion , and the force controllers have closed-loop bandwidths of about 175 Hz.