Identification and control of bilateral telerobot with time delay

Abstract

Telerobotics, the body of science and technology which bridge human control and purely autonomous machines, is expected to be a merging point of modern developments in robotics, control theory, cognitive science and computer science. A telerobot helps the human operator feel and control the remote pre-unknown environment as if he/she is at the remote site, which is usually called "telepresence". However, the transmission time delay between master manipulator and slave manipulator causes instability of the telerobot system and bad "telepresence" of the human operator. In this paper, a new adaptive and passive control scheme based on active impedance matching is proposed to guarantee stability and transparency of the bi-lateral telerobot system. An adaptive impedance term which is active and should adapt to the impedance of environment is defined in this new control scheme. A genetic algorithm (GA) is used to directly identify parameters of the environment impedance, because the GA can success in the search for global optimum when the search space is not differentiable or linear in the parameters.