In order to satisfy the requirement of ultraprecise feeding and positioning of massive parts in the domains such as ultraprecise optical engineering, a nano⁃positioning system that is suitable for the large load situation is presented in this paper. Double closed⁃type air⁃lubricated guide rails are used in the design of this nano⁃positioning stage, which is driven by the double piezoelectric actuators combined with flexible hinge. A capacitance displace⁃ment sensor is used to monitor the motion of the load bearing stage and realize feed⁃back control of the closed loop, which effectively compensates the nonlinearity and hysteresis of piezoelectric actuators and reduces the turbulences caused by release of stress. The application of the double⁃rail air⁃lubricated bearing stage in the traditional transmis⁃sion gear composed of pure flexible hinge greatly enhances the load ability of the system. The capacitance displace⁃ment sensor in place of the dual⁃frequency laser interferometer or strain gauge sensor ( SGS) resistor⁃type displace⁃ment sensor simplifies the requirement of the system operation, especially the measurement system for environment, and also guarantees the position precision of feeding and the stability in a long time. The range of the nano⁃positio⁃ning stage can reach 10μm with a precision of ±2 nm in the situation of bearing 100 kg load. Experimental results show that the large⁃load nano⁃positioning stage can satisfy the needs of ultraprecise position of massive parts.%在超精密光学工程等领域，为了满足大质量部件的超精密进给定位应用需求，设计并研制了一种大载荷的纳米定位平台。该纳米微动承载台采用双闭式气浮导轨，由压电陶瓷致动器结合柔性铰链提供驱动，通过电容微位移传感器实时监测终端承载台位移并实现闭环反馈控制，有效地克服了压电陶瓷致动器的非线性影响因素，并消除了系统由于形变或应力释放等因素产生的不确定性干扰。在传统纯柔性铰链传动机构上增设了双导轨气浮承载台，显著增强了系统的载荷能力，气浮均化效应也提高了系统进给运行的直线性，双压电推拉式驱动方式提高了系统结构刚度，电容微位移传感器取代双频激光干涉仪或电阻式位移传感器的应用，降低了系统运行尤其是测量系统对环境条件苛刻的要求，也保证了平台进给的定位精度和长期稳定性。在载荷为100 kg情况下，定位精度达±2 nm，行程大于10μm。实验结果表明，大载荷纳米微动台能够满足大质量部件的纳米级超精密定位需求。
展开▼
