基于子系统的非线性时变系统辨识方法  

New Identification Method for Nonlinear Time-Varying System Based on Subsystem

作　　者：陈腾飞[1] 何欢[1] 何成 陈国平[1] CHEN Tengfei;HE Huan;HE Cheng;CHEN Guoping(State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics Nanjing,210016,China;Key Laboratory of Unmanned Aerial Vehicle Technology,Nanjing University of Aeronautics and Astronautics Nanjing,210016,China)

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,南京210016 [2]南京航空航天大学无人机研究院,南京210016

出　　处：《振动．测试与诊断》2020年第5期865-872,1019,共9页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(11472123,11602105);机械结构力学及控制国家重点实验室研究基金资助项目(南京航空航天大学)(MCMS-I-0118G01);江苏省自然科学基金资助项目(BK20160782)。

摘　　要：针对非线性时变系统提出一种基于子系统的辨识方法,用于时变多自由度(multiple degree-of-freedom,简称MDOF)系统中非线性的定位和估计,并且无需关于系统的先验知识。所提出的新方法提供一个连续时间模型,MDOF系统按照自由度被分解为不同的子系统。设计正交化算法和误差减小率(error reduction ratio,简称ERR),可以确定子系统中质量和自由度之间的线性及非线性连接的所有信息。在辨识过程中,时变参数的时间表达式可以由新方法准确给出。用一个3自由度(degree-of-freedom,简称DOF)集中质量系统和一个机械臂结构的辨识过程为例,对所提出的方法进行验证。由于简单性及高效性,此方法将在实际工程中取得广泛的应用。In this paper,a new identification method for nonlinear time-varying system based on subsystem is proposed.This new method can be used to locate and estimate the nonlinear characteristics of the multidegree-of-freedom(MDOF)dynamic system without a priori knowledge regarding the system.A MDOF system can be partitioned into a number of different subsystems with a continuous-time model provided by the new method.All the information about the masses and linear or nonlinear connections in the subsystems can be determined with an orthogonality algorithm and an error reduction ratio(ERR)calculation.In this identification process,the time expressions of the time-varying parameters are also given.This new method is demonstrated by a 3DOF lumped mass system and a mechanical arm structure.This new proposed identification method has a wide application prospect in practical engineering for its simplicity and efficiency.

关 键 词：非线性时变系统 参数辨识 子系统 正交三角分解 误差减小率计算 

分 类 号：TH113.1[机械工程—机械设计及理论] O302[理学—力学]