机床结合部耦合动刚度的辨识与建模

发布时间：2018-02-25 10:19

本文关键词： 机床结合部耦合动刚度辨识　出处：《上海交通大学学报》2015年09期 　论文类型：期刊论文

【摘要】：针对结合部动力学中耦合动刚度的辨识与建模问题,通过频响矩阵建立了结合部动力学理论模型,基于力学平衡条件与位移兼容条件推导了动刚度辨识公式.辨识过程中将难测频响矩阵作为中间变量,避免了估算难测频响所引入的方程误差,构建了包含辨识关系的矛盾方程.通过广义逆矩阵对动刚度进行等效处理,讨论了刚度信息之间的耦合关系,提出了结合部耦合动刚度的建模方法,建立了刚度信息不同程度耦合的动力学模型.最后,基于LMS试验平台进行了现场试验,获得了良好的试验效果,证明了该方法的可行性.对比分析了不同动力学模型的预测效果,结果表明:结合部动刚度耦合关系对动力学模型的低频预测性能影响显著,动力学建模时考虑刚度信息的耦合关系是必要的.
[Abstract]:Aiming at the problem of identification and modeling of coupling dynamic stiffness in joint dynamics, the theoretical model of joint dynamics is established by frequency response matrix. Based on the compatibility condition of mechanical balance and displacement, the identification formula of dynamic stiffness is derived. In the process of identification, the difficult frequency response matrix is taken as the intermediate variable, and the equation error caused by estimating the difficult frequency response is avoided. The contradiction equation including identification relation is constructed. The coupling relation between stiffness information is discussed through the equivalent treatment of dynamic stiffness by generalized inverse matrix, and the modeling method of coupling dynamic stiffness is proposed. A dynamic model with different coupling of stiffness information is established. Finally, a field test based on the LMS test platform is carried out, and a good test result is obtained. The feasibility of this method is proved. The prediction results of different dynamic models are compared and analyzed. The results show that the coupling relation of dynamic stiffness of the combined part has a significant effect on the predictive energy of the low frequency of the dynamic model. It is necessary to consider the coupling relation of stiffness information in dynamic modeling.
【作者单位】：四川大学制造科学与工程学院;
【基金】：国家科技重大专项课题项目(2013ZX04005-012)
【分类号】：TG502.3

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