无速度传感器音圈式快速刀具的阻尼闭环控制

针对音圈式快速刀具阻尼较小、超调较大的开环特性,经典控制采用速度环和位置环双闭环反馈控制,但速度传感器增加了系统的复杂度,且易带来附加噪声.基于二阶积分器串联系统的最速控制方法,提出了采用最速过渡环节调节输入或控制信号阻尼,进而改善无速度传感器的输出阻尼前馈控制方法,设计了相应闭环控制方案,在DSP控制平台上进行刀具动态性能测试,并进行了球形透镜阵列的加工实验.实验结果表明:所提出的控制方法能有效改善快速刀具的阻尼特性,刀具方波响应超调约4％,上升时间仅为3 ms,所加工球透镜阵列具有良好的面形精度及表面粗糙度,PV值约为0.228λ,表面粗糙度Ra小于15 nm.

Damping Feed-forward Closed-loop Control for Voice-coil Fast Servo Actuator without Velocity Sensor

Low damping and large overshoot of voice-coil fast servoactuator(VCA) were its natural open-loop characteristics.In order to improve the dynamic performance and steady accuracy of VCA,a double closed-loop feedback control structure was used with a velocity loop and a position loop in classical control strategy.It was inevitable to add complexity and bring additional noise to fast tool servo(FTS) system for the use of velocity sensor.Based on the time-optimal control idea of the two order integrator series s...