针对微操作与微装配任务对多维大范围精密定位运动的需求，采用粘滑驱动原理并结合压电柔顺机构设计二自由度、大行程、无耦合并联定位平台。利用桥式机构对内置压电驱动器进行位移放大，并与复合解耦结构配合构成二维柔顺驱动机构。交叉滚柱导轨则连接移动台与驱动机构，并通过预紧螺钉调整接触摩擦力，进而获得良好的粘滑运动特性。采用有限元法建立定位平台的静力学模型，并对位移放大倍数、应力和固有频率进行仿真分析。最后，搭建实验测试系统验证定位平台的输出性能。实验结果表明：在扫描驱动模式下，驱动电压为150 V时，平台x和y向的输出位移分别为63.84 μm和62.61 μm，耦合比为0.52%和0.59%，分辨率为6.5 nm和7.2 nm；在步进驱动模式下，驱动电压为120 V时，平台在x和y向的单步位移分别为47.31 μm和47.20 μm，耦合比为0.69%和0.73%，x正向、x反向、y正向和y反向的运动分辨率分别为0.49，0.47，0.47和0.42 μm，最大垂直负载为50 N，设计的压电粘滑定位平台满足所需性能要求。

Aiming at the multidimensional， extensive range， and precision positioning requirements regarding micromanipulation and micro-assembly tasks， two degree-of-freedom （DOF） parallel positioning platforms with large strokes and no coupling are designed. A bridge-type mechanism was adopted to amplify the displacement of the built-in piezoelectric actuator， and combined with a composite decoupling structure to form a two-dimensional compliant driving mechanism. Crossed roller guides connected the moving stage with the driving mechanism and adjust the contact friction via preload screws， thus good stick-slip motion characteristics were realized. Then， a finite element method was used to establish the static model of the positioning stage， and the displacement amplification， stress， and inherent frequency were simulated and analyzed. Finally， an experimental test system was built to verify the output performance of the positioning platform. The results show that in the scanning drive mode， when the driving voltage is 150 V， the output displacements of the platform in the x- and y- directions are 63.84 and 62.61 μm， respectively. Further， the coupling ratios are 0.52% and 0.59%， and resolutions are 6.5 nm and 7.2 nm， respectively. In the stepping drive mode， when the driving voltage is 120 V， the single-step displacements of the platform in the x- and y- directions correspond to 47.31 and 47.20 μm， respectively. In addition， the coupling ratios are 0.69% and 0.73%； motion resolutions in x-forward， x-reverse， y-forward， and y-reverse are 0.49， 0.47， 0.47， and 0.42 μm， respectively； and the maximum vertical load is 50 N. The designed piezoelectric stick-slip positioning platform thus meets the required performance requirements.