Influence of Tracking Error on the Contouring Accuracy in Parallel Kinematics Machining (2008)

Kuhfuß, B.; Schenck, C.; Amirian, G.:

2nd International Conference on Computing and Solutions in Manufacturing Engineering (CoSME’08), September 25th - 27th 2008, Brasov/Romania


In contrast to serial kinematic machine tools the motion of the machine axes in parallel kinematics machines (PKM) are translated to the tool center point (TCP) nonlinearly. In this paper the effects of the forward transformation of the tracking errors in PKM are addressed with experiments and simulations. Here the contour error originated from servo tracking system in PKM is presented. This problem is illustrated with a simple one degree of freedom (DOF) setup and the effect on trace accuracy is discussed by a Tripod mechanism. In the simulation phase, two different PKM such as Monopod and Tripod are modelled. The models are performed with constant length of strut and mechanic effects like inertia, flexibility, friction and backlash are neglected. To eliminate the error, a method is introduced that reduces contour errors that are determined by tracking errors in multi axis parallel kinematics machines such as Tripod.