【摘要】 粘滑式压电驱动平台能实现高精度的大行程运动,它由微动台和滑块组成,而微动台的低阻尼振动限制了粘滑式压电驱动平台的运动速度。为了解决这一问题,提出了一种基于主动阻尼的复合控制策略(PI-DPF-FF)。首先,对输入的锯齿波信号进行滤波,使其更平滑。接着,采用时滞位置反馈控制器来主动提高微动台的阻尼,抑制振动。选用跟踪控制器和改进型零相位误差跟踪控制器来减小跟踪误差,提高跟踪带宽。最后,在粘滑式压电驱动平台的样机上对PI-DPF-FF控制器进行了验证。实验结果表明:与常规的比例积分控制器相比,PI-DPF-FF控制器将微动台跟踪带宽由32.7Hz提高到1 466.5 Hz。当系统输入占空比为0.2和频率为100 Hz的信号时,与常规的前馈控制器相比,PI-DPF-FF控制器将滑块角速度由3.52mrad/s提高到9.03mrad/s,平台运动速度有了明显的提高。更多还原

【Abstract】 A piezo-actuated stick-slip device,which consists of a micro-motion stage and a slider,can realize long-range motions with high resolution.Induced mechanical vibrations in the micro-motion stage impose an upper bound on the speed of the piezo-actuated stick-slip device.To address this issue,this study proposes a composite control scheme with active damping.First,the saw-tooth wave signal is filtered and made smoother.Then,a delayed position feedback controller is introduced to improve the damping of the micro-motion stage and mitigate its vibrations.Both tracking and feedforward controllers are designed to reduce the tracking errors and increase the control bandwidth.Finally,the proposed controller is implemented on the prototype of a piezo-actuated stick-slip rotational device.The experimental results show that,compared to a proportional integral controller,the proposed controller improves the control bandwidth from 32.7 to 1 466.5 Hz.In addition,compared to a conventional feedforward controller,the proposed controller under a 100-Hz saw-tooth wave signal with a duty cycle of 0.2 improves the angular velocity of the slider from 3.52 to9.03 mrad/s.The device angular speed is improved significantly.更多还原