惯组小系统动力学建模与非线性特性分析  

Dynamic modeling and nonlinear characteristic analysis of inertial navigation system

作　　者：商霖[1] 张海瑞[1] 赵晓宁[1] SHANG Lin;ZHANG Hairui;ZHAO Xiaoning(China Academy of Launch Vehicle Technology,Beijing 100076,China)

机构地区：[1]中国运载火箭技术研究院,北京100076

出　　处：《中国惯性技术学报》2021年第1期126-132,共7页Journal of Chinese Inertial Technology

基　　金：国家自然科学基金项目(U20B2028)。

摘　　要：基于“三心重合”的设计思想和飞行器的姿态需求,建立了含立方项非线性刚度的惯组小系统动力学模型。提出了惯组小系统存在系统动刚度和减振器动刚度的“双层级”概念。利用龙格-库塔法求解渐软非线性系统对正弦扫频激励的响应,得出减振器动刚度存在对激励幅值和激励频率的敏感区域,采用动刚度曲线表征了减振器的非线性软化特性。利用虚弧长延拓法计算惯组小系统的非线性频响函数和传递特性,预示了高量级振动下减振器的动力失稳现象。通过惯组小系统传递特性试验,验证了减振器具有渐软刚度的非线性特性。扫频法计算结果与正弦扫频试验结果的吻合度达到96.5%,检验了构建模型的正确性。所建立的模型工程应用简便,对惯组小系统非线性特性的预示具有较高的精度,可供飞行器姿控系统设计时参考。Based on the design idea of three-center coincidence and the posture requirements of missile flight,the dynamic model of inertial navigation system(INS)with cubic nonlinear stiffness is established.The two-level concept of dynamic stiffness for INS and rubber damper is put forward.The response of INS to sine-sweep excitation is solved by Runge-Kutta method,it is found that the dynamic stiffness of rubber damper is sensitive to excitation amplitude and frequency,and the nonlinear softening characteristic is characterized by dynamic stiffness curve.The nonlinear frequency response function and transfer characteristics of INS are calculated by using the pseudo-arclength continuation method,and the dynamic instability phenomenon of shock absorber under high order vibration is predicted.The nonlinear characteristics of the shock absorber with asymptotic soft stiffness are verified through the transfer characteristic test of INS.The coincidence degree between the calculated results and the sinusoidal sweep test results reaches 96.5%,which verifies the correctness of the model.The model is easy to apply in engineering and has a high precision in predicting the nonlinear characteristics of INS,which can be used as a reference for the design of attitude control system of aircraft.

关 键 词：惯组小系统 非线性动力学模型 动刚度 频响函数 传递特性 

分 类 号：TJ760.1[兵器科学与技术—武器系统与运用工程] TH113.1[机械工程—机械设计及理论]