车辆随机振动的协方差分析方法

Covariance Analysis Method for Vehicle Random Vibration

随着车辆行驶速度的提高 ,旅客舒适度和行车安全性受到损害。为了有效分析这一问题 ,在车辆动力学的基础上引入激励成型滤波器和感觉成型滤波器 ,将“路—车—人”三者耦合成为一个整体动力学系统 ,建立完整的理论计算模型 ,对轨道不平顺 ,线性及非线性车辆模型及振动对人作用产生的感觉进行综合分析。轨道几何不平顺为平稳的正态分布和各态历经的随机变量。用多刚体系统动力学推导车辆系统运动方程。以协方差分析法在时域进行理论建模分析。引入感觉成型滤波器产生输出信号以评定振动对人体反应程度。通过求解里雅普诺夫方程直接得出有关重要参数的方差值。因为是求解线性代表方程组 ,计算速度快 ,免去频率分析法需要对谱密度函数进行积分的困难 ,适用于非线性及时变系统的分析 ,适于应用现代控制理论进行车辆系统动态特性 (包括舒适度及安全性 )的控制 ,对多输入和多输出实现定量分析与综合性能控制 ,可有效分析高速车辆动力学特性。

Along with the increase of the running speed of trains, the feeling of comfort and the safety of running are impaired. To analyze this issue effectively, the stimulation modeling filter and the sense-forming filter are introduced on the basis of vehicle dynamics. The relationship of Road-Vehicle-Man is coupled to a whole dynamics system, and a full theoretical model is established. The influence of the track irregularity, the linear and nonlinear vehicle dynamic system model and vibration on passenger feeling is comprehensively analyzed. The track geometry irregularity is a stable normal distribution and state-history random variable. Equation of motion of vehicle system is deduced by multi-rigid-body system dynamics. The theoretical modeling analysis in the time domain is performed with covariance analysis method. Feeling forming filter is introduced to output signal for assessing the response of human body to vibration. The variance of related important parameter is acquired by solving liapnov equation. Thanks to the linear algebra equation set, the calculation is fast and the difficulties of frequency analysis requiring the integral to spectral density is avoided. The model is applicable to nonlinear and inconstant system analysis, and also suitable to the control of car system dynamics characteristics (including comfort and safety) by using modern control theory, realizing the analysis and the control of multi-input and multi-output. It is able to analyze high-speed car dynamics characteristics effectively.