Lyapunov function based bilateral control for teleoperation system with time varying delay

Abstract

Recently, robotic surgical support systems are in clinical use for minimally invasive surgery. In order to improve the operability of the robotic surgical systems, development of haptic forceps teleoperation systems is required to help surgeon's dexterity. In addition, the motion scaling, which can adequately reduce or enlarge the movements and tactile senses of the operator and the robot, is necessary to assure safety of the surgery. On the other hand, communication time delay is inevitable in teleoperation systems, which may cause instability of the teleoperation systems. Therefore, stability of the system must be guaranteed in the presence of the communication time delay between master device and slave device. We have developed a multi-DOF robotic forceps manipulator using a novel omnidirectional bending mechanism, and for the developed robotic forceps manipulator, we proposed a passivity based bilateral control that enables motion scaling in both position tracking and force tracking, and guarantees the stability of the teleoperation system in the presence of constant time delay, so far. In this paper, the passivity based bilateral control is extended so as to guarantee the stability of the teleoperation system not only in the presence of the constant time delay but also in the presence of the time varying delay.

Robust control for switched systems with parametric uncertainties

“…However, many real dynamic systems have hybrid nature [57]. The union between advanced control techniques and hybrid paradigm have been highly successful to deal with problems such as: air traffic control [84], automotive control [4], bioengineering [15], flight control processes [55,29], road systems [47], manufacturing [17], teleoperated robotic systems [49], robotic assembly tasks, [62], power switching electronic [75], and others.…”

“…The master is a joy-stick manipulator that was designed and built by reconstruction of a ready-made combined with conventional forceps, which enables to control bending, grasping and rotary motions of the DSD manipulator. The operator can feel a reactive force generated by electric motors, the operation force is detected by strain gauges, and the variation of position is measured by encoders mounted in electric motors [49]. The teleoperation system and force mechanism for bending force are illustrated in This system was built based on the need to improve the operability of the robotic surgical support system, to help surgeon's dexterity.…”