Time Domain Passivity Control-based Telepresence with Time Delay

Abstract

This paper analyses the Time Domain Passivity Control approach in the time-delayed telepresence context, and proposes a method which provides stable operation. The passivity controller for the two-port network which is created by the bilateral control and communication elements in [1] is shown to be not valid if a time delay is introduced in the communication channel. Classical stability analysis for the delayed system is presented and used as argument and benchmark for the proposed solution. Simulations and experimental results are discussed and compared with classical stability analysis.

Bilateral energy transfer in delayed teleoperation on the time domain

“…V). The Slave Controller (N3) acts as a virtual coupling, tuned in order to grant stability and desired performance in the ideal case, where no delay is present in the control loop and the system is considered in the continuous time domain [8]. (i.e.…”

Control of haptic interaction : an energy-based approach

“…Ye et al (2008Ye et al ( , 2009Ye et al ( , 2010 propose a power-based instead of an energybased TDPC approach. This simplified implementation of the TDPC does not contain an integral action and is therefore not susceptible to a possible and undesirable build up effect as reported in the energy-based TDPC approach by Kim and Hannaford (2001), , and Artigas et al (2006). However, the amount of energy 'dissipated' in the control algorithm due to the power-based formulation will increase with respect to the energy-based formulation.…”

“…Iqbal and Roth (2006a,b) implement Kalman Filters to predict the energy at the slave side in order to deal with time delays. Artigas et al (2006Artigas et al ( , 2007 introduce Forward and Backward PO's and PC's to enforce passivity of the communication channel. Artigas et al (2008Artigas et al ( , 2009) extend this approach with a passive coupling between the control algorithm and the physical world.…”

“…As the energy flows are made explicit the formulation of Chapter 1 Ryu and Preusche (2007) is perfectly robust with respect to time-varying delays. It was recognized that the approach by Artigas et al (2006) and Ryu and Preusche (2007) conceptually serve the same purpose and merged into a single unified approach detailed in Ryu et al (2010). This approach has been applied in Artigas et al (2010a,b).…”

“…This problem due to energy build up is associated with TDP algorithms in general and ad-hoc resetting schemes have been proposed for the TDPC approach by e.g. and Artigas et al (2006). It should be noted that the mentioned unstable behavior is actually potentially unstable behavior, as non-passive behavior (generation of "virtual" energy) is a required, but not sufficient condition for instability.…”