A rigorous framework for interactive robot control

Abstract

This paper presents a rigorous, analytical framework for interactive control methods such as sti ness and impedance control. This paper does not present a novel synthesis method for robot control design. Rather, it presents a proper framework to analyse controllers for robots whose purpose is to interact energetically with the environment.First geometrical tools are introduced that are used in kinematic and dynamic analysis of the spatio-mechanical systems common in robotics.`Port behaviour' and`behavioural deviation' are then de®ned both intuitively and rigorously. The utility of this framework is demonstrated by a non-trivial example. Concepts of the behavioural approach are used. NomenclatureQ con®guration space X work space A actuator con®guration space U actuator signal input space M measurable variable space E euclidian Space T¤ X tangent bundle of X T ¤ X cotangent bundle of X T r;s X tensor bundle of type … r; s † T¤ X p tangent space of X at p 2 X T ¤ X p cotangent space of X at p 2 X T r;s X p tensor space of type … r; s † at p 2 X C a ne connection on X k C parallel w.r.t. connection C F free¯ow space E free e ort space pr … n † nth prolongatioñ W W port outcome space W extended port outcome space U universe of port outcomes B port behaviour T £W W

Transparency in Port-Hamiltonian-Based Telemanipulation

“…First, we want to provide a framework for the evaluation of transparency for generic, possibly nonlinear and delayed, port-Hamiltonian-based telemanipulators. Using the concept of port behavior [17], it is possible to obtain an index that measures how much realistic the feeling perceived by the user is when he/she is interacting with the remote environment by the telemanipulator. Analogously to what happens for the design of an intrinsically passive telemanipulation system, it is possible to split the design of a transparent telemanipulator into the transparency optimized design of its parts.…”

Control of haptic interaction : an energy-based approach

“…Transparency will still be subjected to the required need for stability, but far less when compared to the application of linear control systems. Transparency analyses and metrics based on port behavior of general non-linear systems have been proposed by Stramigioli, Fasse and Willems (2002) and Secchi et al (2008b).…”

On autonomous and teleoperated aerial service robots

“…Inspired by the framework for interactive robot control proposed in [110], a transparency analysis for a port-Hamiltonian based teleoperation, in which the communication channel is characterized by scattering variables, is proposed. Although this time-domain definition is more general than its most commonly used frequencydomain counterpart, its applicability is only demonstrated in simulation for 1D teleoperation system, whose interconnection between the master and slave system is through power ports.…”

“…To provide objective tool to measure transparency, an inspiration is drawn from [110] and a time-domain approach is followed. To that end, each one of the seven functional blocks representing a generic teleoperation scheme are represented by a generic state space representation, see Fig.…”

“…It should be noted that it is also possible to evaluate the behavioral deviation at the slave robot side as well, see [103], [110].…”