新型二维并联柔性结构微动平台的设计

Design of a new 2-DOF micro-positioning stage based on parallel flexible structures

为克服串联式和现有并联式二维柔性微动平台的不足，基于Stewart并联机构思想来设计二维并联柔性微动平台的新构型。首先，基于结构简单紧凑、固有频率高、便于传感器安装等要求，采用Stewart并联机构并对其进行相应的结构改变，设计出了具有对称双圆弧薄板式弹性单元体的2-DOF并联柔性结构微动平台新构型；其次，采用有限元方法对平台的尺寸参数进行了优化，并对其静动态特性进行了仿真分析；最后，通过试验对平台的性能进行了测试。结果表明：在150V电压下时，平台X和Y方向的位移分别为22．88μm和23．25μm；平台X和Y方向的固有频率分别为1．712kHz和1．706kHz；在10N的阶跃输入力作用下。平台X和Y方向的响应时间均约为20ms。

In order to overcome deficiency of 2-DOF series and the existing parallel micro-positioning stage, a new parallel 2-DOF micro-positioning stage was developed based on the principle of Stewart parallel mechanism. First, according to the requirements of the stage that simple and compact structure, high natural frequency and flexibilityof sensorintegration, the new 2-DOF parallel flexible structure micro positioning stagewith elastic elements of dual arc flexible thin plate was designed. The elastic elements were modified from the morphology of the Stewart parallel mechanism. Then the geometry parameters of the stage were optimized,and the static and dynamic characteristics of the stage were analyzed using finite element method. Finally, the static and dynamic characteristics of the micro stage were tested experimentally. The results show that： the displacements of the stage in x and y directions under the max driving voltage of 150 V are 22.88 μm and 23.25 μm, respectively. The natural frequencies of the stage in x, y directions are each 1.712 kHz and 1.706 kHz. The response time of the stage in x and y directions are both 20 ms under the input step force of 10 N.