Study on the integration of attitude control and vibration control of the superspeed railway vehicle

本研究旨在分析利用可变连杆机构补偿乘客所感受到的横向加速度和内外轨间车轮负载不平衡的倾斜轨道车辆的基本动力学特性。第一部分分析了旋转中心与重心的几何关系以及四连杆的位置。在此基础上，推导了四连杆机构轨道车辆车身摆摆运动方程，分析了摆摆运动的动态稳定性和固有频率随连杆参数和车身参数的变化规律。利用这些方程，从理论上研究了作用于车底的横向加速度和内外轨之间的不平衡轮载，并从理论上得到了摆运动的固有频率。实验结果验证了采用连杆机构的倾斜轨道车辆的几何和动力学模型。第二部分进行理论分析，寻找“完美的倾斜条件”，即连杆机构的几何参数集能够同时提供零横向加速度和零轮载不平衡。通过改变linl机构的可变长度，可以获得理想的倾斜条件。最后，针对车身倾斜系统，对变连杆机构进行前馈和反馈补偿，以实现在弯曲截面上的完美倾斜条件。利用液压作动器激励的实验装置，模拟了倾斜车身在弯曲轨道上的动态特性。通过与实验结果的比较，进行了计算机仿真，验证了该系统的有效性。

This study aims to analyze fundamental dynamical characteristics of a tilting railway vehicle using variable link mechanism for compensating both lateral acceleration that passengers feel and wheel load unbalance between inner and outer rails.In the first part, geometric relations between the center of rotation and the center of gravity and positions of four-links were analyzed. Then equation of the pendulum motion of railway vehicle body with four-link mechanism was derived for analyzing dynamic stability and natural frequency of the pendulum motion that depends on the link parameters as well as vehicle body parameters. Using these equations, lateral acceleration acting on the vehicle floor and unbalanced wheel load between inner and outer rails were theoretically studied and the natural frequency of the pendulum motion was theoretically obtained. These geometric and dynamic models of the tilting railway vehicle using link mechanism were verified by experiment results.In the second part, theoretical analysis is conducted to find "perfect tilting condition", that is, a geometric parameter set of link mechanism that can provide both zero lateral acceleration and zero wheel load unbalance simultaneously. This perfect tilting condition can be obtaine by changing the variable length of linl mechanism.Finally, to realize the perfect tilting condition on curved section, feed-forward and feedback compensations for the variable link mechanism are applied to this tilting vehicle body system. The experimental set-up that is excited by hydraulic actuators is used to simulate the dynamic characteristics of the tilting vehicle body on the curved track. Computer simulation is carried out to verify the effectiveness of this system by comparing with the experimental results.