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experiments and simulations. Furthermore, the current vs. torque frequency response of the MR actuator is examined to evaluate its applicability to torque control. The bandwidth of the MR actuator is enough high for especially haptic applications.

A manipulator system with a large workspace volume and high payload capacity has greater link flexibility than do typical industrial robots and teleoperators. If link flexibility is significant, position control of the manipulator’s end-effector exhibits nonminimum-phase, noncollocated, and flexible-structure system control problems. This paper addresses inverse dynamic trajectory planning issues of a single-link flexible manipulator. The inverse dynamic equation of a single-link flexible manipulator was solved in the time-domain. By dividing the inverse system equation into its causal part and anticausal part, the inverse dynamic method calculates the feed-forward torque and the trajectories of all state variables that do not excite structural vibrations for a given end-point trajectory. Through simulation and experiment with a single-link manipulator, the effectiveness of the inverse dynamic method in producing fast and vibration-free motion has been demonstrated.

Abstract-A general framework for expanding the time-domain passivity control approach [12], [24] to large classes of control systems is proposed. We show that large classes of control systems can be described from a network point of view. Based on the network presentation, the large classes of control systems are analyzed in a unified framework. In this unified network model, we define "virtual input energy," which is a virtual source of energy for control, and "real output energy" that is physically transferred to a plant to allow the concept of passivity to be used to study the stability of large classes of control systems. For guaranteeing the stability condition, the time-domain passivity controller for two-port [24] is applied. Design procedure is demonstrated for a motion control system. The developed method is tested with numerical simulation in the regulation of a single link flexible manipulator. Totally stable control is achieved under wide variety of operating condition and uncertainties without any model information.

Background Despite its high lesion accessibility and versatility, endoscopic platforms have suffered from designing flexible manipulators with high payload capability sufficient to perform advanced endoscopic procedures. Methods A flexible robotic platform, K‐FLEX, has been developed with a design of 17 mm in overall diameter. To overcome the shape distortion and deflection in payload handling, a strong continuum manipulator has been designed to have maximum resistance to the distortion. The kinematic analysis and mapping strategy have been established for the master‐slave teleoperation. Results The proposed manipulator has shown 7.5 mm in trajectory variation to lift the weight of 300 g. Finally, the feasibility of the integrated K‐FLEX system has been verified through three kinds of simulated surgical tasks. Conclusions The initial prototype of the proposed robot showed the possibility of advanced endoscopic surgery with improved payload capability.