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排序方式: 共有722条查询结果,搜索用时 15 毫秒
581.
M. Ganesan Jijo Benni 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(11):1764-1786
In this paper, a new approach to model reference based adaptive second-order sliding mode control together with adaptive state feedback is presented to control the longitudinal dynamic motion of a high speed train for automatic train operation with the objective of minimal jerk travel by the passengers. The nonlinear dynamic model for the longitudinal motion of the train comprises of a locomotive and coach subsystems is constructed using multiple point-mass model by considering the forces acting on the vehicle. An adaptation scheme using Lyapunov criterion is derived to tune the controller gains by considering a linear, stable reference model that ensures the stability of the system in closed loop. The effectiveness of the controller tracking performance is tested under uncertain passenger load, coupler-draft gear parameters, propulsion resistance coefficients variations and environmental disturbances due to side wind and wet rail conditions. The results demonstrate improved tracking performance of the proposed control scheme with a least jerk under maximum parameter uncertainties when compared to constant gain second-order sliding mode control. 相似文献
582.
简要介绍了耙吸挖泥船泥舱泥门的发展演变,以及有关设计要素和经验数据,通过统计数据表明大通径单列泥门的耙吸船近年来在国外呈上升趋势,同时对大通径单列泥门在国内的发展前景表示乐观。 相似文献
583.
介绍客车厂生产客车专用驾驶员门的现状、存在的问题、简易改进方案,以及由专业厂研发生产给不同客车厂的配套与生产的优势。 相似文献
584.
象山铁路隧道斜井有轨运输溜车分析及防控措施 总被引:1,自引:1,他引:0
防止溜车是斜井有轨运输施工及运输安全管理的重中之重,在新建龙岩至厦门铁路象山隧道斜井有轨运输施工中,通过运输管理实践,总结分析了有轨运输斜井溜车的各种原因,提出相应的针对性防控措施,确保了斜井有轨运输的安全。 相似文献
585.
高伟 《电力机车与城轨车辆》2009,32(6):17-19
针对既有防空转防滑行系统存在的不足,通过理论分析、大量实践调研,并参考国内外最新研究成果,开发了新型防空转防滑行系统。新系统能实时检测各轮对黏着状态,自动控制达到最大牵引力,在大秦线SS4改型机车的运行考核中取得良好效果。 相似文献
586.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(6):855-869
This paper deals with the dynamic behaviour of tyres and it is aimed at describing their dynamic features in the frequency band above 1 kHz, a range difficult to manage due to measurement noise and to the unreliability of numerical models, where the main influence is that of tread and blocks. Measurements have been made possible by fixing three three-axial micro-electro-mechanical system accelerometers on the liner and exciting the tyre under test by means of a dedicated test bench, suitably designed and constructed. Different kinds of tests have been considered in this research and described in the present paper. All of them show that a strong link exists between contact phenomena and tyre response in the frequency band over 1 kHz. This field is dominated by the tread and block dynamic responses. Furthermore, it is shown that vibrations of a sliding tyre give contributions in that frequency range for the above-mentioned reasons. It is thought that the study of the tyre behaviour over 1 kHz, though affected by significant uncertainties, can provide a proper knowledge to improve breaking effectiveness. 相似文献
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