Application of H∞ control design techniques to improve dynamics of dexterous manipulation

Abstract

ABSTRACT The applicability of H control design methods to the analysis and design of manipulator impedance control is presented.Direct application of existing H control design algorithms is shown to result in an ill-posed MIMO impedance designproblem. A three-part impedance control design methodology is developed and shown to be well-posed. This methodologyutilizes FL control design tools to find the controller minimizing the weighted distance, measured in the Hc sense, betweenthe realized and the specified manipulator impedances. A connection is made between the design of the three parts of thecontroller, and torque-based versus position-based impedance control design. A design example is presented derived using thisthree-part design methodology. Although the design procedure guarantees the resulting impedance controller will be stable forthe design conditions, it is shown that the resulting controller may be non-passive even if the desired impedance is passiveand the distance between the realized impedance and the desired impedance is small.