Evaluation of influence of target location on robot repeatability

This paper evaluates the influence of target location on robot repeatabilit y. An experiment was set up to analyze the effect of the three-dimensional target location on robot repeatability. An error-analysis model to determin e repeatability based on the robot's kinematic model and known robot parame ters was developed. Experimental results indicated that there was a signifi cant statistical difference between repeatability at different locations in the workspace and that the height of the target point influenced repeatabi lity. Experimental results tended to those derived from the error-analysis kinematic model. Hence, to determine the optimal target location, there is no need for extensive experimentation; instead, only a few target points ca n be sampled and compared to an error-analysis model.