Authors: Donatien Nganga-Kouya, Maarouf Saad, Francis A. Okou
Addresses: Department of Mechanical Engineering, Ecole Normale Superieure d'Enseignement Technique, B.P. 3989 Libreville, Gabon ' Department of Electrical Engineering, Ecole de Technologie Superieure, 1100 Notre-dame west, Montreal (Quebec) H3C 1K3, Canada. ' Department of Electrical and Computer Engineering, Royal Military College of Canada, P.O. Box 17000, Station Forces, Kingston, Ontario K7K 7B4, Canada
Abstract: A new hybrid force-position control method for uncertain robotic manipulator interacting with its environment is presented. First, the system dynamical model in the compliance frame is derived from the usual joint frame model and leads to two sets of equations due to the constraint associated to the contact surface. Next, the two dynamics are separately used for the synthesis of position and force tracking controllers. For the position control part, the design method consists of an estimated-parameters dependent coordinate transformation and a control law derived from a backstepping procedure. The force control law has two aspects: first it compensates the dynamical interaction between the end-effector motion and the force induced by the environment and secondly, it imposes a desired force using a proportional-like equation. Finally, a parameter-adaptation algorithm is derived from a stability criteria and dependent both on the position and force tracking errors. Simulation results on a four-degree of freedom robotic system tracking a triangle while maintaining a constant contact force prove the effectiveness of our solution.
Keywords: robotic manipulators; hybrid force-position control; adaptive control; backstepping; robot control; uncertainty; system dynamics; modelling; position control; force control; tracking control; stability; robot simulation.
International Journal of Modelling, Identification and Control, 2011 Vol.13 No.1/2, pp.97 - 107
Published online: 31 May 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article