Adaptive Teleoperation Transparency Based On Impedance Modeling

Transparency is a method proposed to quantify the telepresence performance of bilateral teleoperation systems. It is practically impossible to achieve transparency for all frequencies, however, previous research has shown that by proper manipulation of the individual transfer functions, transparent systems for limited frequency bands can be designed. In this paper we introduce a diierent approach. We rst study the problem of designing systems that are transparent only for a given value of the output impedance, then, by combining this concept with that of time-adaptive impedance estimation, we postulate a new strategy for the design of transparent systems. In the proposed method, the output impedance estimate is updated at each time instant using adaptive ARMA modeling based on either the LMS or RLS algorithms. The current estimate of the output impedance is used to update some free-design system parameters in such a way that the system tries to achieve transparency We refer to this strategy as asymptotic transparency. An example on how to use this strategy in the design of a system with position-forward and force-feedback paths is included.