Decoupled haptic transmission by multilateral control

In this paper, a noble bilateral control method is introduced to realize decoupled haptic transmission technology. At first, bilateral system based on acceleration control is discussed. Acceleration control is accomplished by disturbance observer. Both of master and slave are controlled by position regulator and force servoing, and these two controllers are decomposed into two modes "common mode" and "differential mode" in the virtual space. Decomposed controller helps to control position and force information individually. Second, the bilateral control is extended and generalized as a multilateral control, which based on the decomposed controller. In the proposed multilateral control, interactivity and synchronism are achieved easier than conventional control. Third, to realize decoupled haptic information, IR(identity ratio) is introduced into differential mode. IR shows ratio of each input in the common mode. Although slave robot is controlled by a numbers of masters, each of masters can feel the real environment by using IR. Fourth, numerical simulation and experimental results are shown. Proposed method is easy to expand to infinite dimension. As a minimum dimension of the multilateral control, the series of experiments are conducted by three robots. The numerical simulation and experimental results shows the viability of the proposed method.