Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining equipment. Most active vibration-isolation systems (AVIS) have been developed based on static loads. When a vibration-isolation load changes dynamically during ultra-precision turning lathe machining, the system parameters change, and the efficiency of the active vibration-isolation system based on the traditional control strategy deteriorates. To solve this problem, this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control (GA-BP-PID), which can automatically adjust the control parameters according to the machining conditions. Vibration-isolation simulations and experiments based on passive vibration isolation, a PID algorithm, and the GA-BP-PID algorithm under dynamic load machining conditions were conducted. The experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load conditions. This design is reasonable and feasible.