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651.
In this article, the properties of active and semi-active suspension for heavy goods vehicles are compared. The criteria for the comparison are the RMS sprung mass vertical acceleration, RMS dynamic tyre force, and suspension power consumption. The active system is based on an air-spring with controlled in-flow and out-flow of the air. In the semi-active system, a controlled hydraulic damper is employed. The results concerning the semi-active suspension system were taken from the article by Besinger et al. [Besinger, F.H., Cebon, D. and Cole, D.J., 1995, Force control of a semi-active damper. Vehicle System Dynamics, 24(9), 695–723.].  相似文献   
652.
This article presents two design strategies for an active rear wheel steering control system. The first method is a standard design procedure based on the well-known single track model. The aim of the feedback loop is to track a reference yaw rate in order to improve the handling behaviour. Unfortunately, a reasonable specification of the reference yaw rate proves to be a nontrivial task. A second approach avoids this drawback. The structure of the controller is regarded as a virtual mass-spring-damper system with adjustable parameters. Due to the high abstraction level of this method, the controller parameters can be tuned intuitively. Experiments with a prototype vehicle illustrate the effectiveness of the two proposed methodologies.  相似文献   
653.
In this work, a lateral vehicle dynamics control based on tyre force measurements is proposed. Most of the lateral vehicle dynamics control schemes are based on yaw rate whereas tyre forces are the most important variables in vehicle dynamics as tyres are the only contact points between the vehicle and road. In the proposed method, active front steering is employed to uniformly distribute the required lateral force among the front left and right tyres. The force distribution is quantified through the tyre utilisation coefficients. In order to address the nonlinearities and uncertainties of the vehicle model, a gain scheduling sliding-mode control technique is used. In addition to stabilising the lateral dynamics, the proposed controller is able to maintain maximum lateral acceleration. The proposed method is tested and validated on a multi-body vehicle simulator.  相似文献   
654.
Block diagram representations of both conventional wheelsets and wheelsets with independently-rotating wheels are developed, with the objective of giving insights from a control engineering viewpoint for studies of actively-controlled wheelsets. The analysis predicts a quasi-kinematic oscillation with independently-rotating wheels which has not been reported before. It also identifies possibilities for control approaches which might be used to stabilise a wheelset without affecting steady-state curving performance.  相似文献   
655.
介绍了自组织理论概要及形成条件,在此基础上提出基于自组织的柴油机PM排放达标控制,并进行了软、硬件开发;最后,系统在485Q柴油机台架上进行了实验,证明其有较好的响应性,可实现对系统的控制功能。  相似文献   
656.
为了改善发动机的工作状况,利用微机控制技术,采用自动控制理论,建立了发动机振动主动控制模型.采用LQR控制、自调整模糊控制、神经网络自适应控制3种策略,以发动机振动加速度作为控制目标,对其振动进行有效的在线控制.验证了控制系统的控制效果和跟踪性能,分析了各种控制策略的优缺点.  相似文献   
657.
主动前轮转向控制技术研究现状与展望   总被引:4,自引:0,他引:4  
主动前轮转向系统提供的独立于驾驶员的转向干预可以提高车辆的操纵稳定性.文中介绍了横摆角速度反馈和横摆角速度与侧偏角联合反馈的稳定性控制算法;阐述了主动前轮转向系统分别与几种动力学控制系统实行集成控制的方法.最后在结论中指出底盘一体化控制将是主动转向技术未来的发展方向.  相似文献   
658.
对于模数转换器(ADC),电容失配所产生的误差是一种主要的非线性误差源.分析了采样保持电路的工作原理和由电容失配产生的误差,并利用有源误差平均技术对文中采样保持电路进行误差平均.在采样频率为100MHz情况下,输入偏移量为0.75V,振幅为0.375V,频率为2.5MHz的正弦差分信号,经误差平均电路后电容失配造成的误差由1.1mV降至0.8μV,证明了有源电容失配校准方法的有效性.  相似文献   
659.
This work deals with the nonlinear control of a marine diesel engine by use of a robust intelligent control strategy based on cerebellar model articulation controller (CMAC). A mathematical model of diesel engine propulsion system is presented. In order to increase the accuracy of dynamical speed, the mathematical model of engagement process based on the law of energy conservation is proposed. Then, a robust cerebellar model articulation controller is proposed for uncertain nonlinear systems. The concept of active disturbance rejection control (ADRC) is adopted so that the proposed controller has more robustness against uncertainties. Finally, the proposed controller is applied to engine speed control system. Both the model of the diesel engine propulsion system and of the control law are validated by a virtual detailed simulation environment. The prediction capability of the model and the control efficiency are clearly shown.  相似文献   
660.
海洋平台振动模糊控制研究   总被引:1,自引:0,他引:1  
周亚军  赵德有 《船舶力学》2004,8(3):116-123
在过去的三十年里,模糊逻辑控制在结构振动控制中得到了广泛的研究和应用.模糊逻辑控制具有很强的鲁棒性并且能够有效地处理非线性以及被控系统和外载荷的不确定性和不精确性,本文对于海洋平台振动模糊控制进行了研究.通过模态阻尼比的不确定性显示了模糊控制的鲁棒性,研究表明海洋平台的振动模糊主动控制是有效的、可行的,并且提高了平台的适用性和生存性.本文的方法毫无疑问为今后的海洋平台振动控制提供了一条新的途径.  相似文献   
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