Title :
Flexible joint control: Robustness analysis of the collocated and non-collocated feedbacks
Author :
Alazard, D. ; Chretien, J.P.
Author_Institution :
CERT-ONER/DERA, Toulouse, France
Abstract :
The robustness and performance properties of a proportional-derivative controller applied to a very flexible joint are discussed. Because of a flexible mode due to in-joint compliance, the classical collocated control does yield good rigid mode dynamics with a correct phase margin in low and high frequency, and noncollocated control does not allow correct damping of the rotor mode. The simultaneous analysis of discrete root loci and Nicholas plots leads to a phase control law with a derivative term built from both input and output velocities. Simulations taking into account various real nonlinearities and measurement imperfections are proposed to validate this improved control design
Keywords :
manipulator dynamics; Nicholas plots; Robustness analysis; collocated control; control design; damping; derivative term; discrete root loci; feedback; flexible joint control; in-joint compliance; input velocities; measurement imperfections; noncollocated control; nonlinearities; output velocities; performance; phase control law; phase margin; proportional-derivative controller; rigid mode dynamics; rotor mode; simulations; space manipulators; Control design; Feedback; Gears; Manipulators; Orbital robotics; Payloads; Robust control; Service robots; Torque control; Velocity control;
Conference_Titel :
Intelligent Robots and Systems '93, IROS '93. Proceedings of the 1993 IEEE/RSJ International Conference on
Conference_Location :
Yokohama
Print_ISBN :
0-7803-0823-9
DOI :
10.1109/IROS.1993.583920
