Improvement of the machining accuracy of milling robots

This paper presents an approach to improve the machining accuracy of milling robots. The low static stiffness of industrial robots leads to huge deflections of the tool. Hence, robotic milling can only be applied for tasks with low accuracy requirements and minor cutting forces (e.g., deburring or trimming). To expand the application fields of industrial robots in milling operations, a new methodology to increase the machining accuracy was developed at the Institute of Machine Tools and Industrial Management (iwb) of TU Munich. The methodology consists of a model-based fuzzy controller for the compensation of the (static) path-deviation and a method to identify the necessary stiffness parameters of the robot with low experimental effort. The approach was implemented on a robot of Type KUKA KR 240 R2500 prime and validated by milling test.