关键词: 双电机精密传动机构, 动力学模型, 间隙非线性, 复合消隙方法

Abstract: Aiming at the problems of large speed fluctuation and impact caused by the gaps between the two transmission chains of the dual-motor precision transmission mechanisms, the method of eliminating the gaps of the system was studied. First, a mechanism dynamics model including the meshing clearances between the output gear of the planetary reducer and the large ring gear was established. Through the model simulation, the influences of the gap size on the system characteristics were analyzed. Then, a compound anti-backlash method was proposed combining dynamic bias torque based on speed command and cross-coupling synchronous control based on differential negative feedback. An experimental device for dual-motor precision transmission mechanisms was built, and the verification experiments of the anti-backlash method were carried out. The experimental results show that in the case of closed-loop speed, the proposed compound anti-backlash method may ensure the complete elimination of the system gaps, and may improve the system speed tracking accuracy by 73.38%, and the shock amplitude in the start-up phase may be attenuated by 76.35%. The research results lay a certain foundation for the research of the high-precision control method of the double-motor precision transmission mechanisms, and provide a reference scheme for the elimination of the gaps in the gear transmission systems. 

Key words: dual-motor precision transmission mechanism, dynamics model, backlash nonlinearity, composite anti-backlash method