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排序方式: 共有962条查询结果,搜索用时 15 毫秒
61.
舵阻摇H∞控制器的设计 总被引:12,自引:5,他引:7
舵阻摇的效果对船舶水动力参数敏感,H_∞控制器对模型不确定性具有良好的适应性。本文设计了一种基于并联控制模式的舵阻摇H_∞控制器。模拟海上航行条件的计算机仿真表明该控制器具有良好的鲁棒特性。 相似文献
62.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1265-1285
This paper deals with in-curve vehicle lateral behaviour and is aimed to find out which vehicle physical characteristics affect significantly its stability. Two different analytical methods, one numerical (phase plane) and the other graphical (handling diagram) are discussed. The numerical model refers to the complete quadricycle, while the graphical one refers to a bicycle model. Both models take into account lateral load transfers and nonlinear Pacejka tyre–road interactions. The influence of centre of mass longitudinal position, tyre cornering stiffness and front/rear roll stiffness ratio on vehicle stability are analysed. The presented results are in good agreement with theoretical expectations about the above parameters influence, and show how some physical characteristics behave as saddle-node bifurcation parameters. 相似文献
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Mengxuan Song Nan Wang Timothy Gordon 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(8):1090-1107
ABSTRACTThis paper studies the low-speed manoeuvring problem for autono-mous ground vehicles operating in complex static environments. Making use of the intrinsic property of a fluid to naturally find its way to an outflow destination, a novel guidance method is proposed. In this approach, a reference flow field is calculated numerically through Computational Fluid Dynamics, based on which both the reference path topology and the steering reference to achieve the path are derived in a single process. Steering control considers three constraints: obstacle and boundary avoidance, rigidity of the vehicle, plus the non-holonomic velocity constraints due to the steering system. The influences of the parameters used during the flow field simulation and the control algorithm are discussed through numerical cases. A divergency field is defined to evaluate the quality of the flow field in guiding the vehicle. This is used to identify any problematic branching features of the flow, and control is adapted in the neighbourhood of such branching features to resolve possible ambiguities in the control reference. Results demonstrate the effectiveness of the method in finding smooth and feasible motion paths, even in complex environments. 相似文献
65.
主要阐述影响双层观光车侧倾稳定性的各项因素;对比分析后,提出采用四个高度控制阀的改进方案,最终通过出口认证试验。 相似文献
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Marlies Mischinger Martin Rudigier Peter Wimmer Andreas Kerschbaumer 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(8):1108-1125
ABSTRACTThis paper describes a method to analyse and evaluate different trajectory planning methods and controller types for usage in automated vehicles. Its application is shown by using a novel trajectory planning approach considering comfort aspects (based on Rapidly Exploring Random Tree (RRT)), two different controllers to follow the planned path (cascade controller and flatness based controller) and a simulation method to obtain resulting lateral vehicle accelerations. The method is used to plan and drive a trajectory through a roundabout. It can be seen that the lateral accelerations of the controller-driven vehicle are in the range of the values used for planning. However, the results of both controllers show differences in lateral deviation and in smoothness of lateral accelerations. The simulation results are then compared to real-world test drives in the same roundabout. The measured lateral accelerations are in the same range as well but show a smoother progression than the two controller models. 相似文献
68.
H.T. LIN 《西南交通大学学报(英文版)》2012,20(2):70-75
Vortex motion in superconductors of higb-Tc superconducting maglev system is studied by a computational simulation.The vortex system is treated in a similar fashion,as a system where defects arc arrang... 相似文献
69.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):867-884
This paper investigates optimal roll control of an experimental articulated vehicle. The test vehicle and the mathematical model used to design the control strategies are presented. The vehicle model is validated against experimental data from the test vehicle in passive configuration. The initial controller design, performed by Sampson (Sampson, D.J.M. and Cebon, D., 2003a, Achievable roll stability of heavy road vehicles. Proc. Instn. Mech. Engrs, Part D, J. Automobile Engineering, 217(4), 269–287), is reviewed and adapted for the experimental vehicle. The effect of not controlling all the axles on the vehicle is investigated and a variable vehicle speed controller is designed by interpolating between constant speed controllers. Substantial reduction in normalized load transfer is achieved for a range of manoeuvres, both in steady-state and transient conditions. 相似文献
70.