摘要
为了提高超精密定位系统的定位精度和行程,设计一种新型的单级驱动气动伺服定位平台。以金属波纹管为执行机构,以气浮导轨支撑,研究无摩擦条件下的较大行程的精密控制。为减少建立PI模型时的算子数量,减小求逆过程的计算量,提高建模精度,改进基本迟滞算子,建立基于广义迟滞算子的广义PI模型,并对模型进行验证。给出广义PI模型的求解析逆方法。设计基于广义PI逆模型的复合控制方案,并进行试验研究。结果表明,基于广义逆模型的阶跃响应系统的定位精度达到30 nm,锯齿波和复频跟踪试验输入下,基于PI逆模型的跟踪精度平均误差为0.96μm和0.63μm,基于广义PI逆模型的跟踪精度平均误差为0.49μm和0.45μm。试验数据表明改进广义PI模型对于增加系统定位精度有效。
In order to improve the accuracy and stroke of the ultra-precision positioning stage, a new type of pneumatic servo positioning stage with single driving device is designed. Metal bellows are used as driving device in the positioning stage, the stage is supported by air flotation sliders to realize large stoke and ultra-precision positioning. In order to reduce the number of operators and to improve modeling accuracy, hysteresis operators are modified to build the generalized PI model, and the model is validated too. A solution of the inverse generalized PI model is given. The compounding controller is designed based on inverse generalized PI model. Experiments are implemented on the step signal, sawtooth signal and multifrequency signal. The results show that the positioning accuracy of the step response is less than 30 μm, the average tracking errors on sawtooth and multifrequency input are 0.96 μmand 0.63μm based on the PI model, and the average tracing errors are 0.49 μm,and 0.45 μm based on generalized PI model. Experiments show that the generalized PI model is effective for increasing the positioning accuracy of the stage.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2015年第2期198-206,共9页
Journal of Mechanical Engineering
基金
国家自然科学基金(51375045)
流体动力与机电系统国家重点实验室开放基金(JZKF-201214)资助项目
关键词
广义迟滞
波纹管
超精密
复合控制
generalized hysteresis
bellows
ultra-precision
compounding control
