摘要
为了研究二自由度系统的载荷响应,获取响应参数,设计了二自由度系统自由振动响应参数的实验平台,分析了各因素对实验数据的影响,提出了一种基于曲线拟合方法获取自由振动物理参数识别的方法。将两弹性梁构成的单自由度单元通过弹簧耦合到一起组成二自由度系统,利用LMS振动测试仪采集到系统耦合之后的时域数据;通过1st Opt软件中麦夸特法(LM)+通用全局优化法(UGO)法来实现时域数据的曲线拟合,从而获取自由振动响应参数。结果表明:LMUGO可以凭借其极强的寻优能力和鲁棒性,很好地拟合了实验响应数据,求出了响应参数,是处理曲线拟合有力的工具。经过对相关系数、最小残差值等进行评价,证明了拟合方法的有效性。
In order to study the load response of two degree of freedom( 2-DOF) system,to get the response parameters,the experimental platform of the response parameters of 2-DOF free vibration was designed. The impact of various factors on the experimental data were analyzed,and a method was presented to get physical parameters identification of free vibration based on curve fitting method. A 2-DOF system was formed by two elastic beams with 1-DOF unit coupled by spring,time-domain data were collected by LMS vibration tester after couping of the system. The response parameters of free vibration were gotten from the curve fitting of time-domain data by using Levenberg-Marquardt plus Universal Globe Optimization( LM-UGO) method of 1st Opt. The results show that LM-UGO can fit the experimental response data excellently by relying on its strong optimization ability and robustness,calculate the response parameters,which is a powerful tool to deal with curve fitting. The validity of the fitting method is proved by the evaluation method,such as the correlation coefficient,the minimum residuals and etc.
出处
《机床与液压》
北大核心
2016年第3期71-74,共4页
Machine Tool & Hydraulics
基金
国家自然科学基金资助项目(50675037)