Absolute stability analysis of sampled-data scaled bilateral teleoperation systems

Abstract

Stability of a bilateral teleoperation system may be jeopardized by controller discretization, which has been shown to involve energy leaks. This paper proposes a novel approach to analyzing the absolute stability of sampled-data bilateral teleoperation systems consisting of discrete-time controllers and continuous-time master, slave, operator, and environment. The proposed stability analysis permits scaling and delay in the master and the slave positions and forces. The absolute stability conditions reported here impose bounds on the gains of the discrete-time controller, the damping terms of the master and the slave, and the sampling time. A design-related application of these results is in proper selection of various control parameters and the sampling rate for stable teleoperation under discrete-time control. To explore the trade-off between the control gains and the sampling time, it is studied how large sampling times, which require low control gains for maintaining stability, can lead to unacceptable teleoperation transparency and human task performance in a teleoperated switching task. This shows that the effect of sampling time must be taken into account because neglecting it (as in the absolute stability literature) undermines both stability and transparency of teleoperation. The resulting absolute stability condition has been verified via experiments with two Phantom Omni robots.

Bilateral teleoperation system stability with non-passive and strictly passive operator or environment

“…In the second approach, port 2 is assumed to be a right-or left-shifted RHP and the resulting driving-point impedance at port 1 becomes a disc, which should be entirely in the RHP for stability of the coupled two-port network. In Jazayeri et al (2013), the second approach is applied when the terminations are non-passive rectangular impedance or right-shifted RHP impedances. In both the above work, the stability analysis is applied to a PEB-controlled bilateral teleoperation systems.…”

A visual supporting system for teleoperation of robot arm using visual servo control

“…Several kinds of researches have been made on the teleoperation of robots from its importance [1][2][3][4]. On the other hand, the control methodologies of robots by employing the visual information acquired from cameras have also been energetically studied for a few decades (See [5] and references therein).…”

Nonlinear bilateral teleoperators under event‐driven communication with constant time delays

“…Recently, several researches have focused on the stability issue of discretization in teleoperation systems, resulting from the Internet and control algorithms in computer systems. [25][26][27][28][29] Based on passivity technique, the passivity property of sampled-data teleoperation systems was studied by imposing on damping, sampling time, and control gains. 28 In the presence of time delays, an interesting result was presented with an absolute stability condition for sampled-data teleoperators.…”