Research on an evaluation model for the working stiffness of a robot-assisted bonnet polishing system

• DOI: 10.1016/j.jmapro.2021.03.013
• Publication Date: 2021-03-27T03:08:45Z
• Authors: Ri Pan; Wanying Zhao; Zhenzhong Wang; Shuting Ji; Xiangsheng Gao; Dongju Chen; Jinwei Fan
• Keywords: Foundation (evidence); Direct stiffness method; Chemical Mechanical Planarization

Abstract Robot-assisted bonnet polishing systems (RABPSs) have been widely studied in order to expand the application of bonnet polishing technology. Currently, low working stiffness is one of the most important problems that needs to be solved for RABPSs. To address this issue, an evaluation method for the working stiffness of RABPSs should be studied. Therefore, a theoretical and experimental study is presented in this paper. First, the static stiffness model of the RABPS was built based on the Denavit–Hartenberg (D–H) method and the compliance matrix. Subsequently, the force characteristics of the RABPS during the bonnet polishing process were analyzed. Next, by combining the above static stiffness model and the force analysis results, a new index, that is, the normal stiffness coefficient (NSC), was proposed to evaluate the working stiffness of the RABPS. Finally, the performance of the NSC of the RABPS was verified by simulation and experiment. Both results show that the NSC has higher accuracy than other commonly used indexes when it is used to describe the working stiffness of RABPSs. This research provides an important theoretical foundation for the optimization of the working stiffness of RABPSs for future studies.