Basic Algorithm of Controlling Passive Force Display System with Redundant Brakes

Force information in virtual space is important and often required for tele-operation, training, amusement, design supporting, and other virtual reality systems. While passive force display which uses only passive elements is an effective method for assuring safety, it has some directions and link postures which are hard to present force. To this problem, a method for improvement of controllability using redundant couple of brakes had been suggested. This method was able to make it possible to display various force directions and various postures of virtual objects. The purpose of this study was further improvement of controllability of systems with redundant couple of brakes. In this paper, we discussed the outline of developed redundant-type system and basic experiments with it. We also mentioned an algorithm how to use the brakes to represent various positions and orientations of virtual objects. It was confirmed by experiments in some typical cases.

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