Modeling and experimental investigation of Cartesian compliance characterization for drilling robot

Industrial robot due to its high flexibility and low cost is wildly used in many areas. However, the low stiffness properties are the main limitation to the application of industrial robots in the field of precision machining. This paper addresses a modeling method of the Cartesian compliance for a drilling robot. The stiffness characterization in the drilling axial direction is analyzed, and the diversity of the axial stiffness in different robot postures is investigated. Based on the Cartesian compliance model, a quantitative evaluation index of the robot drilling performance is defined. Finally, experiments were developed on KUKA KR500-2 robot to validate the correctness of the model proposed, and specific conclusions regarding the robot compliance characterization are presented.