Predicting Path Inaccuracies in Robot-based Machining Operations Using Inverse Kinematics

摘要

Machine tools are dominating the machining sector because of their high reliability in process accuracy. On the other hand, industrial robots provide an opportunity for use in applications with fewer process requirements. They offer a high cost-benefit ratio in comparison to conventional machine tools, due to their low investment costs and high flexibility. Low absolute accuracy, low structural stiffness as well as missing consistent process planning tools – designed for industrial robots – prevent an industrial breakthrough. In particular, process planning tools provide a lot of potential for compensating process inaccuracies. This paper presents an approach for predicting path inaccuracies of machining operations using industrial robots. Using the inverse kinematics, rotatory axes’ progressions are calculated for predicting critical switching movements that could lead to high path deviations. On this basis, process parameters like the clamping position or motion strategies will be optimized in order to reduce the number of switching points.