This article proposes a dual motor anti backlash rack and pinion transmission mechanism for the longitudinal feed system of CK61250 heavy-duty CNC lathe. This mechanism is different from fixed preloading and simple master-slave tracking electric preloading dual motor schemes. It adopts a master-slave control architecture that integrates real-time adjustable preloading force, disturbance observer, and stiffness error compensation framework. The force position decoupling dual motor layout is adopted, and mechanical preloading is not set. The control layer includes adaptive preloading adjustment and active cutting force suppression content. The relevant content has been verified through frequency domain stability margin analysis, interference suppression ratio evaluation, and comparison with single motor system simulation. The single motor system has problems such as transmission clearance, elastic deformation, and vibration noise. The maximum thrust of the system is 50 kN, the fast moving speed is 12 m/min, and the full stroke positioning accuracy is better than ±0.015 mm. A comprehensive error mathematical model has been developed, and sensitivity analysis shows that thermal deformation and control errors account for 38% and 22% of the overall positioning error.
Ren et al. (Fri,) studied this question.