动态特性可调的微动平台优化设计

Optimization Design of Micro-Motion Stage With Adjustable Dynamic Characteristics

针对目前柔性铰链主要靠局部变形来工作,其存在应力集中,且微动平台的动态特性受材料特性、设计制造等误差影响,难以满足变工况条件下的高精密位移输出。基于应力刚化原理,采用对称布置的带倒角的弹片式柔性铰链,设计张紧力调节机构,实现微动平台的动态特性可调。采用COMSOL Multiphysics和MATLAB联合仿真对张紧力调节机构进行参数优化,让调节机构保持线性调节关系,使柔性铰链的应力分布最小化。结果表明,所设计的微动平台能够进行高度线性固有频率调节,与有限元分析结果相比,频率调节范围相差2.55%,在理论设计范围内。

Since the flexure hinge mainly works by the local deformation, and the stress concentration exists, and the dynamic characteristics of the micro-motion stage are influenced by material properties, designing and manufacturing errors, it is difficult to meet the high precision displacement output under variable working conditions. Based on the principle of stress stiffening, a tension adjusting mechanism is designed by using symmetrically arranged elastic flake flexible hinge with chamfering angle to realize the adjustable dynamic characteristics. The co-simulation of COMSOL Multiphysics and MATLAB is used to optimize the parameters of the tension adjustment mechanism so that the adjustment mechanism can maintain the linear adjustment relationship and minimize the stress distribution of the flexible hinge. The results show that the designed micro-motion stage can perform highly linear natural frequency adjustment. Compared with the finite element analysis results, the range of frequency adjustment is different by 2.55%, which is within the theoretical design range.