Modelling and Measurement of Industrial Manipulators for High-Precision Contact Applications

Abstract: This study was conducted with the objective of predicting the accuracy of robotic manipulator models in contact applications. A number of computational robot models, including lumped-parameters models and flexible-body elastic models were used and refined to evaluate the behavior of a manipulator under static, quasi-static and dynamic loading conditions. The simulations were then compared with experimental measurements conducted in the forms of static, quasi-static and dynamic compliance-evaluation series. Additionally, contact application models were constructed and utilized to simulate and assess the associated accuracy level of contact processes involving robotic manipulators. Results included comprehensive joint-space maps of the manipulator with respect to stiffness which showed the high dependency of the compliance on the configuration of the robot. Computational estimations of heavy-duty contact applications with robotic manipulators predicted the occurrence of self-excited oscillations and low stiffness of the robot when compared to traditional CNC machines. Recommendations and guidelines are derived based on the results to improve the current state of the art and overcome the challenges associated with these applications in the future