A Study on Robot Arm Machining: Advance and Future Challenges

Nowadays, it is not uncommon to find news and research about robotic machining applications, as milling and drilling.The flexibility, programmability and low price of robots, conversely to CNC machines, makes robotic machining an interesting opportunity for manufacturing of large parts.In this paper, the authors show the current advances on developments of robotic machining and a theoretical framework of the process, evidencing its weaknesses and strengths.Since the low stiffness of robots is their main disadvantage, the target of researchers is to improve this characteristic, and therefore avoid adverse effects like vibration, which influences the machining accuracy.The last developments can be categorized according to their research field: modelling and control of the process, robot workspace optimization, redundancy analysis, vibrating/chatter analysis and new designs and methodologies for the improvement of machining.These researches increase the efficiency and accuracy of the process with the goal to convert robots in a real alternative to CNC machines.In fact, the authors are working on the aim of proposing a characterization of several machining operations with robots, considering a force/torque control that provide the system a feedback with the improved stiffness matrix to correct errors and improve the accuracy during machining.