This study focuses on a piezo-actuated two-degrees-of-freedom (2-DOF) decoupled compliant micro-positioning stage driven by a novel compound bridge-type amplification mechanism embedded with Scott-Russell mechanism. According to the system identification, the transfer functions of two working directions are obtained. Both of the measured dynamic cross couplings between them are also lower than −40 dB, demonstrating that the single-input-single-output control strategy can be adopted reasonably. Based on the identified frequency response, a fractional order proportional-integral (FOPI) controller is designed for the 2-DOF compliant micro-positioning stage. Compared with the integer order proportional-integral (IOPI) controller using same parameters, the amplitude error of the FOPI controller is 2% lower than that of IOPI controller. Additionally, a fractional order zero phase error controller (FOZPETC) is designed by obtaining the inverse of the fractional order closed-loop system in a large frequency range. And the gain of the corrected control system is 1 in a wide frequency band to eliminate the phase error in the close-loop control system. Finally, using the compound control strategy of FOZPETC+FOPI, a series of trajectory tracking tests are carried out on the proposed novel 2-DOF compliant micro-positioning stage. All the experimental results prove that the designed controller can achieve good positioning and tracking performance of the micro-positioning stage, and confirm the effectiveness of the compound control strategy of FOZPETC+FOPI.

这项研究的重点是由嵌入 Scott-Russell 机制的新型复合桥式放大机制驱动的压电驱动的双自由度 (2-DOF) 解耦柔顺微定位平台。根据系统辨识，得到两个工作方向的传递函数。测得的两者之间的动态交叉耦合也低于-40 dB，表明可以合理采用单输入单输出控制策略。基于确定的频率响应，为符合 2-DOF 的微定位平台设计了分数阶比例积分 (FOPI) 控制器。与使用相同参数的整数阶比例积分（IOPI）控制器相比，FOPI控制器的幅度误差比IOPI控制器低2%。此外，通过在大频率范围内获得分数阶闭环系统的逆，设计了分数阶零相位误差控制器（FOZPETC）。并且修正后的控制系统在宽频带内增益为1，以消除闭环控制系统中的相位误差。最后，利用FOZPETC+FOPI的复合控制策略，对所提出的新型2-DOF兼容微定位平台进行了一系列轨迹跟踪测试。实验结果均证明所设计的控制器能够实现微定位平台良好的定位和跟踪性能，证实了FOZPETC+FOPI复合控制策略的有效性。