基于轻量化设计的编码器安装座动刚度研究

Dynamic Stiffness of Encoder Mounting Bracket Based on Lightweight Design

目的为了提高编码器的检测精度,对编码器安装座的频率拓扑优化进行研究,以实现结构轻量化,并提高其动刚度特性。方法依据编码器安装座的实际工况,利用HyperMesh对编码器安装座进行有限元前处理。以编码器安装座受载节点的频响位移最小化为优化问题的目标函数,以优化前后结构的体积比为约束条件来构建编码器安装座的频响优化模型,并使用OptiStruct进行求解,同时,采用OSSmooth高效地对优化结果进行CAD模型的提取和再分析。结果由优化前后结果对比可得,编码器安装座的动刚度值在x方向忽略不计,y方向由2564.25增大到5932.11,z方向由62500.36增大到109 792.54;一阶固有频率由3860.664 Hz显著增大到8380.32 Hz。结论该方法不仅改善了编码器安装座在工作过程中的动态特性,还降低了编码器安装座的制造材料,实现了结构轻量化的目的。

The work aims to improve the encoder detection accuracy, study the frequency topology optimization of encoder mounting bracket to achieve lightweight structure and improve its dynamic stiffness characteristic. According to the actual working condition of the encoder mounting bracket, the finite element pre-processing was conducted on the encoder mounting bracket based on HyperMesh. With the loading node frequency response displacement of encoder mounting bracket minimized as the objective function of optimization, and the structural volume ratio before and after optimization as the constraint condition, the frequency response optimization model of the encoder mounting bracket was constructed and solved based on OptiStruct. Meanwhile, the OSSmooth was adopted to extract and reanalyze the CAD model of optimized results. The comparison of results before and after the optimization showed that, the dynamic stiffness of the encoder mounting bracket could be ignored in x direction and the value increased from 2564.25 to 5932.11, and from 62 500.36 to 109 792.54 respectively in y and z directions. The first order natural frequency was significantly increased from 3860.664 Hz to 8380.32 Hz. The proposed method not only improves the dynamic property of encoder mounting bracket in the working process, but also reduces its manufacturing material, thus achieving the lightweight structure.