A fast tool servo (FTS) system is developed for the fabrication of non-rotationally symmetric micro-structured surfaces using single-point diamond turning machines.The constructed FTS employs a piezoelectric tube actu...A fast tool servo (FTS) system is developed for the fabrication of non-rotationally symmetric micro-structured surfaces using single-point diamond turning machines.The constructed FTS employs a piezoelectric tube actuator (PZT) to actuate the diamond tool and a capacitive probe as the feedback sensor.To compensate the inherent nonlinear hysteresis behavior of the piezoelectric actuator,Proportional Integral (PI) feedback control is implemented.Besides,a feed-forward control based on a simple feed-forward predictor has been added to achieve better tracking performance.Experimental results indicate that error motions in the performance of the system caused by hysteresis can be reduced greatly and the micro-structured surface is successfully fabricated by implementing the FTS.展开更多
为了弥补快速刀具伺服(fast tool servo,FTS)系统驱动不足的问题,开发了一种电磁驱动直接数字式频率合成器(direct digital synthesizer,DDS)系统来实现高带宽轨迹的跟踪控制方法。利用静态增益实现参数前馈补偿,通过线性控制建立扰动...为了弥补快速刀具伺服(fast tool servo,FTS)系统驱动不足的问题,开发了一种电磁驱动直接数字式频率合成器(direct digital synthesizer,DDS)系统来实现高带宽轨迹的跟踪控制方法。利用静态增益实现参数前馈补偿,通过线性控制建立扰动观测器(disturbance observer,DOB)补偿前馈增益处理。开展实验测试分析,从控制器中采集控制指令,实现对FTS励磁线圈的驱动作用,完成输出位移控制。研究结果表明:采用PAVPF控制器时对谐振峰起到了明显抑制,发挥理想减振作用。通过阻尼控制保持稳定裕度恒定,再通过更高增益PID控制器对系统实施控制,实现系统闭环带宽的显著增加。PAVPF阻尼达到了±2μm误差;提高DOB增益后系统最大跟踪误差降低值接近±0.16μm。该研究具有很好的控制精度,为高精度刀具控制起到理论支撑作用。展开更多
基金Funded by the National High-tech R&D Program ("863" Program) of China (No.2006AA04Z314)
文摘A fast tool servo (FTS) system is developed for the fabrication of non-rotationally symmetric micro-structured surfaces using single-point diamond turning machines.The constructed FTS employs a piezoelectric tube actuator (PZT) to actuate the diamond tool and a capacitive probe as the feedback sensor.To compensate the inherent nonlinear hysteresis behavior of the piezoelectric actuator,Proportional Integral (PI) feedback control is implemented.Besides,a feed-forward control based on a simple feed-forward predictor has been added to achieve better tracking performance.Experimental results indicate that error motions in the performance of the system caused by hysteresis can be reduced greatly and the micro-structured surface is successfully fabricated by implementing the FTS.
