Configuration optimization for end-point stabilization of redundant manipulators with base flexibility

Abstract

Copyright © 2019 ASME.This paper presents a method to determine an optimal configuration of a teleoperated excavator to minimize the inducedundercarriage oscillation for robust end-point stabilization. Theuse of remotely operated robotic excavators for tasks such asmeasurement and reorganization of damaged objects at a disaster site, instead of human responders, is considered as a viableoption. Treating the excavator as a kinematically redundant system, where non-unique combinations of the undercarriage position and arm posture can locate the end-point at the same reference. A specific configuration can be chosen to not excite undercarriage oscillation with simple end-point error feedback controlwithout model-based or measurement-based vibration suppression. Robust stability measures based on normalized coprimefactorization as well as modal decomposition solve the redundancy of the kinematics. An advantage of this approach is thatthe control engineer can proceed as if the excavator arm is fixedto rigid ground, which is practically not the case, and apply simple traditional Jacobian-based end-point control.