基于柔顺机构的二维振动平台设计与分析

Design and Analysis of 2-DOF Vibration Stage Based on Compliant Mechanism

为提高微型零件的加工质量,提出了一种新型压电驱动的二自由度(2-DOF)柔顺振动平台。首先,设计了一种新型的二维柔顺振动平台的结构。柔性铰链关于XZ和YZ平面具有镜像对称性,消除了平台的寄生运动与耦合误差。其次,在理论建模的基础上,建立了二维柔顺振动平台的等效动力学模型,分别通过理论计算与有限元分析研究其动力学和静力学特性,结果表明其一阶固有频率约为4200 Hz,单向驱动时工作行程约为22.6μm,双向驱动时工作行程约为26.4μm。工作台的轴向刚度为16.17N/μm,对于加工复杂表面织构具有重要意义。最后,通过理论分析结果与有限元仿真结果对比分析,验证了二维柔顺振动平台设计的正确性与可行性。

In order to improve the machining quality of micro parts,a novel piezoelectrically actuated two-degree-of-freedom(2-DOF)compliant vibration-assisted stage was presented. First,the new structure of the 2-DOF compliant vibration-assisted stage was designed. The flexible hinge has mirror symmetry about the XZ and YZ planes,eliminating coupling errors and parasitic motion of the stage. Secondly,on the basis of theoretical modeling,the equivalent dynamic model of the 2-DOF compliant vibration-assisted stage was established. The dynamic and static characteristics of the stage were studied by theoretical calculation and finite element analysis. The results show that the first-order natural frequency is about 4200 Hz. Its working stroke is about 22.6μm with one piezoelectric actuator(PEA)and 26.4μm with two PEAs,respectively. The axial stiffness of the stage is 16.17 N/μm,which is of great significance for machining complex surface texture. Finally,through the comparison of theoretical analysis results and finite element simulation results,the correctness and feasibility of the 2-DOF compliant vibration-assisted stage are verified.