Dexterous manipulation in constrained bilateral teleoperation using controlled supporting point

The use of robotic devices in surgical applications has been growing in recent years. Surgical robots are beginning to find applications in minimally invasive surgeries. The control issues pertaining to many of the applications of robotics to surgery are similar. In all cases, the ability to accommodate unique special-purpose mechanical designs is important, as is the ability to restrict the motions of the end-effector. Conventionally, motion constraint is attained by mechanical constraint equipments, such as bearing, linear guide, and so on. In this paper, robot motion control with a controlled supporting point (CSP) for operator aid is proposed. The method is to make the constraint without setting mechanical constraints. The merits of the proposed method are not only the simplification of mechanical equipments but also the deletion of friction at the constraint. It is easy to set the CSP at the position where the setting of mechanical supporting points is difficult. Furthermore, it is also possible to change the CSP online. This method is especially effective for the object whose position of surface is always changing. The proposed method is applied to six-degrees-of-freedom manipulators. The numerical and experimental results show the viability of the proposed method. Index Terms--Bilateral teleoperation, constraint, disturbance observer, environment quarrier, force control, haptics, motion control, surgery robot.