Exoskeleton manipulator for application of electro-magnetic virtual forces

Abstract

This work addresses the fundamental need for continued improvement in human-machine interfaces. Of particular interest is the need for force feedback to the operator to provide the ability to interact physically with the synthetic environment. In order to allow for natural contact and control over the position, orientation, and motions of objects within the computer-generated environment, a new haptic interface device is under development that applies arbitrary forces to the digits of the human hand. The device consists of a mechanical exoskeleton manipulator that maintains a constant position relative to the finger digits by means of an optical feedback tracking system. The design and analysis of the mechanical exoskeleton device and the development of a closed loop control algorithm to track the hand motion are discussed. A dynamic model of ISU exoskeleton is developed and experimental results for the system are presented using some typical virtual environments, including interaction with a 'hard' surface, a simple mass-spring-damper 'yo-yo', and interaction with a compliant 'ball'. These results show that the electro-magnetic interface generates adequate force levels for perception of virtual objects by the exoskeleton.