Magnetorheological elastomer absorber-based chatter suppression in robotic milling

As intelligent and automated technology continues to rapidly advance in aerospace, industrial robots have been becoming a powerful alternative to machine tools in milling processes. However, due to their low stiffness, robots are susceptible to the self-excited chatter during milling, leading to machining failures or even workpiece breakages. It is therefore crucial to suppress the chatter in robotic milling to ensure product performances. Magnetorheological Elastomers (MREs), with their characteristics of adjustable stiffness, fast response, and reversibility, are effective approaches to achieve the chatter absorption. This study focuses on the chatter suppression based on MRE absorbers in robotic milling. Firstly, the robot's vibration mode was obtained using experimental modal analysis, and the chatter frequency during milling was identified. Then, a variable stiffness dynamic absorber utilizing MREs was developed, and its frequency shift characteristics were tested. Finally, a series of chatter experiments for robotic milling were conducted to evaluate the chatter reduction effect of the MRE absorber under different process parameters and robot configurations. Experimental results demonstrate that the chatter acceleration is effectively reduced, and the final surface quality of the machined workpiece and the milling stability are significantly improved, which validates the excellent performance of the MRE absorber for suppressing chatter in robotic milling.