Force-impedance control of a 6-dof parallel manipulator

• Type: Article in International Conference Proceedings Book
• Date: 2009

Authors

António M. Lopes (Author) FEUP; Fernando G. Almeida (Author) FEUP

Scientific classification

FOS: Engineering and technology > Mechanical engineering

Other information

Abstract (EN): An acceleration based force-impedance controller is presented in this paper. The proposed control strategy is II ACCELERATION BASED FORCE-IMPEDANCE applied to a six-dof parallel robotic mini-manipulator: the CONTROL Robotic Controlled Impedance Device (RCID). The control objective of an impedance controller is to The control strategy involves three cascade controllers: an impose, along each direction of the task space, a dynamic inner acceleration controller, built as a set of six Single-Input- relation between the manipulator end-effector position error Single-Output (SISO) acceleration controllers (one per and the force of interaction with the environment, the manipulator axis), an impedance task-space controller, and desired impedance [6] [7] [8]. Usually the desired an outer force controller. impedance is chosen linear and of second order, as in a The proposed control strategy enables two kinds of. manipulator behaviour: force limited impedance control and mass-sprmg-damper system. position limited force control. The type of behaviour only In order to fulfil the task requirements, the user chooses a depends on the chosen manipulator trajectories. desired end-effector impedance that may be expressed by The RCID may be used as a force-impedance controlled (1): auxiliary device, coupled in series with a position controlled industrial robot, or as a stand-alone force feedback display, MAK - Kd)+Bd(x-id)+Kd(X-X)=-fe (1) that may be used as a master manipulator in master-slave telemanipulated systems or as a haptic device interacting with virtual environments. where Md, Bd and Kd are constant, diagonal and positive Experimental results of the RCID used as an auxiliary device definite matrices, representing the desired inertia, damping, working coupled to an industrial manipulator are presented.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6