Crucial geometric error compensation towards gear grinding accuracy enhancement based on simplified actual inverse kinematic model. (1st March 2020) - Xia, Changjiu
Highlights: A novel crucial geometric error compensation method towards machining accuracy enhancement based on simplified actual inverse kinematic model is proposed, which can provide simplified analytical expressions of compensated motion commands. The geometric error modules of motion axes are established for rapid error modeling of a machine tool with arbitrary configuration. Crucial geometric error elements regarding tooth profile and helix deviations are identified by the improved Sobol method. Feasibility and effectiveness of the crucial geometric error compensation method are verified in a TYAZXRCW-type five-axis gear form grinding machine tool. Abstract: The geometric error, which will significantly affect grinding accuracy of the gear form grinding machine tool, should be compensated. This paper proposes a crucial geometric error compensation method towards gear grinding accuracy enhancement, and it can directly obtain simplified explicit analytical expressions of compensated motion commands for more efficient and effective compensation. Firstly, an actual forward kinematic model is established by rapid reconstruction of the geometric error modules of motion axes. Next, the conventional actual inverse kinematic model (IKM) directing at tool posture error compensation is developed to calculate analytical expressions of compensated motion commands. Then, the material removal mechanism of gear form grinding process is considered to construct the geometric error- tooth surface posture error model, which directly reveals the mapping rules between the geometric error and the tooth surface errors. On this basis, the crucial error elements regarding tooth profile and helix deviations are identified based on global sensitivity analysis, and the compensated expressions obtained by the actual IKM are further simplified and modified directly towards gear accuracy enhancement. Finally, the crucial error identification and compensation process was verified by both numerical analysis and machining tests. The results show that tooth profile deviations will reduce by more than 80% theoretically but only by 43.27% in fact due to other errors, and it proves the feasibility and effectiveness of the proposed method.