论文部分内容阅读
在复杂曲面或功能结构的超精密车削以及主动误差校正车削中,利用快速刀具伺服(FTS)受到了学术界和工程界的广泛关注.然而,无论采用哪一种驱动方式,FTS皆存在难以模型化的迟滞非线性,从而制约了FTS跟踪性能的提高.本文利用分数阶微积分理论,针对压电致动型FTS的迟滞非线性建立了等效的分数阶动力学模型,得到了压电致动型FTS的传递函数.利用一种改进的差分进化算法进行了模型参数的辨识.通过正弦波及三角波信号激励的实验结果表明,针对压电致动型FTS所提出的分数阶模型建模误差小于4%,具有预期的模型精度.本研究为FTS的迟滞非线性建模提供了一种简单有效的新方法,对于提高FTS运动轨迹的跟踪控制性能具有重要意义.
FTS has drawn the attention of academics and engineers in the ultra-precision turning of complicated surfaces or functional structures as well as in active error-correcting turning. However, no matter which driving mode is adopted, there are difficult models for FTS The hysteresis nonlinearity is restricted and the tracking performance of FTS is restricted.In this paper, an equivalent fractional dynamics model is established for hysteresis nonlinearity of piezoelectric actuated FTS by using fractional calculus theory, and the piezoelectric induced The transfer function of the moving FTS is studied.An improved differential evolution algorithm is used to identify the model parameters.Experimental results of sine wave and triangular wave excitation show that the fractional model modeling error for the piezoelectric actuated FTS is less than 4% with the expected accuracy of the model.This study provides a simple and effective new method for nonlinear modeling of hysteresis in FTS, which is of great significance to improve the tracking control performance of FTS trajectory.