A cost-effective purely translational parallel robot for rapid assembly tasks

Abstract

The paper deals with the design and the prototype of a 3-DOF parallel robot for assembly, based on the 3-PUU scheme. The research objective is to demonstrate the possibility of realising cost-effective PKM for force-controlled operations such as assembly, surface finishing, deburring. The basic idea is to limit the mechanism cost using off-the-shelf components and to compensate for the loss of accuracy by using suitably impedance control. The machine geometry has been sketched considering the typical requirements of assembly lines, then the dimensional ratios have been optimised on the basis of performance indices of the static behaviour (inverse of the condition number of the Jacobian matrix and condition number of a matrix which describes the moment transmission across the robot structure). The main features of the robot are summarised. The prototype shall be realised within April 2002.