Online compliance error compensation system for industrial manipulators in contact applications

摘要

Industrial manipulators are rarely used in high-force processes even though they provide flexibility, adaptability, relatively low cost, and a large workspace. This limited utilization is mainly due to their inherent low stiffness, which results in significant deformation. Hence, it is necessary to improve their accuracy in order to achieve high-precision requirements while performing tasks under load. This paper focuses on the development and implementation of an online compliance error compensation system for industrial manipulators. The proposed algorithm computes the compensation based on an elasto-geometric robot model and process forces measured with a force sensor mounted between the robot mechanical interface and the end effector. The performance of the compensation system is evaluated experimentally in two high payload robots from different manufacturers in which the compensation was carried out to reduce the mean deformation of circular trajectories under load.