基于薄层单元与弹簧单元的滚动直线导轨副动力学建模

Dynamic modeling on a linear rolling guide based on thin layer element and spring element

针对某大型光机装置中使用的LM型直线导轨-滑块的结合面,采用薄层单元与弹簧单元模拟其接触面,建立了大行程传输结构模拟件的有限元模型。通过模型修正方法,根据模态试验结果对薄层单元弹性模量以及弹簧刚度进行了识别。模型修正后,结构前三阶模态频率计算结果与试验结果最大差别为2.23%,地脉动载荷下各测点位移响应计算结果与试验结果最大差别为7.61%。计算结果与试验结果具有较好的一致性,验证了模型的有效性。

The guide-slider joint of the transmission mechanism with a long stroke has a great effect on the dynamic characteristic of the structure.Aiming at the dynamic modeling on the joint part of the LM linear rolling guide in some large laser facility,the finite element(FE)model of the transmission mechanism with a long stroke is established based on the thin layer element and spring element.The modulus of the thin element and the stiffness of the spring element are identified by the model updating method and the modal experimental results.After the model update,the maximal error of the first three modal frequencies between simulation and experiment is 2.29%,and the maximal error of the point’s displacement response between simulation and experiment is 7.61%under the ambient vibration.The results of simulation and experiment are consistent,which shows that the model is effective and reasonable.The study provides a theoretical basis for the high confidence dynamic modeling on other structure with such a the joint.