Design of Passive Constant‑Force End‑Effector for Robotic Polishing of Optical Reflective Mirrors  

作　　者：Jian Zhang Liangxiao Zhao Lingling Li Fulei Ma Guimin Chen 

机构地区：[1]School of Mechano‑Electrical Engineering,Xidian University,Xi’an 710071,China [2]Xi’an Institute of Optics and Precision Mechanics of CAS,Xi’an 710119,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Institute of Robotics and Intelligent Systems,Xi’an Jiaotong University,Xi’an 710049,China

出　　处：《Chinese Journal of Mechanical Engineering》2022年第6期89-97,共9页中国机械工程学报（英文版）

基　　金：National Natural Science Foundation of China(Grant No.U1913213);West Light Foundation of the Chinese Academy of Sciences(Grant No.XAB2016A10);Shanxi Provincial Key Research and Development Projects of China(Grant No.2018ZDXM-GY-105).

摘　　要：Polishing plays an indispensable role in optical processing,especially for large-aperture optical reflective mirrors with freeform surfaces.Robotic polishing requires effective control of the contact force between the robot and the mirror during processing.In order to maintain a constant contact force during polishing,traditional polishing robots rely on closed-loop control of air cylinders,whose performances heavily rely on high-fidelity force sensing and real-time control.This paper proposes to employ a compliant constant-force mechanism in the end-effector of a polishing robot to passively maintain a constant force between the robot and the mirror,thus eliminating the requirement for force sensing and closed-loop control.The compliant constant force mechanism utilizing the second bending mode of fixed-guided compliant beams is adopted and elaborated for the passive end-effector.An end-effector providing a constant contact force of 40 N is designed and prototyped.The polishing experiment shows that the passive constant-force end-effector provides stable contact force between the robot and the mirror with fluctuation within 3.43 N,and achieves RMS(Root Mean Square)lower thanλ/10(λ=632.8 nm)of the polished surface of the largeaperture optical reflective mirror.It is concluded that the constant-force compliant mechanism provides a low-cost and reliable solution for force control in robotic polishing.

关 键 词：Robotic polishing Fixed-guided compliant beam Constant-force compliant mechanism Passive force control 

分 类 号：TH74[机械工程—光学工程] TP242[机械工程—仪器科学与技术]