Dynamic analysis of reconfigurable fixture construction by a manipulator

In a reconfigurable workholding system, the precise manipulation of fixture mechanisms by robot manipulators is performed against external kinematic c onstraints. Automation of such tasks requires development of dynamic model that can be utilised for establishment of control strategies. The sliding l ower pairs form the basic structure of the fixture mechanisms; thus dynamic analysis of adjustment operations on sliding pairs becomes essential. In t his paper, four types of fixture mechanisms for the reconfigurable workhold ing system are briefly presented. Sliding pairs are identified and briefly described as the basic structure of fixture mechanisms. Geometric and dynam ic analyses for robotic adjustment of sliding pairs with built-in complianc e are presented. The requirements to successfully perform the height adjust ment of such sliding pairs with various geometric parameters are discussed. By taking into consideration the inertial forces and moments, constraint i nequalities are obtained to ensure jam-free condition on sliding pairs duri ng adjustment operations. Generalised inequalities for wedge-free condition are also developed and presented. In addition, the dynamic adjustment algo rithms are discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.