A realization of haptic training system by multilateral control

In recent years, realization of a haptic system is desired strongly in the fields of medical treatment and expert's skill acquisition. An integrated system design of an analysis of interaction between a robot and environment required for stable contact operation, an observation method of reaction force from the environment, and architecture of bilateral control system is absolutely essential for acquisition and reproduction of a vivid tactile sensation. In this paper, haptic training system (HTS) is realized based on multilateral control. The law of action and reaction is attained by three robots. Bilateral control is extended and multilateral control is introduced. Multilateral control is designed similarly as bilateral control based on the modal decomposition; force is controlled in the common mode, and position is controlled in the differential mode. Scaling factors of position and force are set independently. Therefore, it is possible to change a trainer's assistant force according to a trainee's skill level. Proposed training system based on multilateral control will be a fundamental technology for evolution of haptic devices.