Active roll control for rollover prevention of heavy articulated vehicles with multiple-rollover-index minimisation

This paper presents the application of a nominal control design algorithm for rollover prevention of heavy articulated vehicles with active anti-roll-bar control. This proposed methodology is based on an extension of linear quadratic regulator control for ‘state derivative-induced (control coupled) output regulation’ problems. For heavy articulated vehicles with multiple axles, a performance index with multiple rollover indices is proposed. The proposed methodology allows us to compare the usefulness of various control configurations (i.e. actuators at different axles of the vehicle) based on the interaction of this control configuration with vehicle dynamics. Application of this methodology to a specific heavy articulated vehicle with a tractor semi-trailer shows that a single active anti-roll-bar system at the trailer unit gives better performance than multiple-axle actuators at tractor and trailer together with the single lane change manoeuvre as the external disturbance. Thus, the proposed methodology of this paper not only highlights the importance of the interactions between control and vehicle dynamics in rollover prevention problems but, in fact, proposes a novel technique to exploit the benefits of these interactions judiciously.     

An adaptive fuzzy-sliding lateral control strategy of automated vehicles based on vision navigation

Lateral control is considered to be one of the toughest challenges in the development of automated vehicles due to their features of nonlinearities, parametric uncertainties and external disturbances. In order to overcome these difficulties, an adaptive fuzzy-sliding mode control strategy used for lateral control of vision-based automated vehicles is proposed in this paper. First, a vision algorithm is designed to provide accurate location information of vehicle relative to reference path. Then, an adaptive fuzzy-sliding mode lateral controller is proposed to counteract parametric uncertainties and strong nonlinearities, and the asymptotic stability of the closed-loop lateral control system is proven by the Lyapunov theory. Finally, experimental results indicate that the proposed algorithm can achieve favourable tracking performance, and it has strong robustness.     

Driver models for personalised driving assistance

We propose a learning-based driver modelling approach which can identify manoeuvres performed by drivers on the highway and predict the future driver inputs. We show how this approach can be applied to provide personalised driving assistance. In a first example, the driver model is used to predict unintentional lane departures and a model predictive controller is used to keep the car in the lane. In a second example, the driver model estimates the preferred acceleration of the driver during lane keeping, and a model predictive controller is implemented to provide a personalised adaptive cruise control. For both applications, we use a combination of real data and simulation to evaluate the proposed approaches.     

Fatigue analysis of the bow structure of FPSO

The bow structure of FPSO moored by the single mooting system is rather complicated. There are many potential hot spots in connection parts of structures between the mooting support frame and the forecastle. Mooting forces, which are induced by wave excitation and transferred by the YOKE and the mooting support frame, may cause fatigue damage to the bow structure. Different from direct wave-induced-forces, the mooting force consists of wave frequency force (WF) and 2nd draft low frequency force (LF) , which are represented by two sets of short-term distribution respectively. Based on two sets of short-term distribution of mooting forces obtained by the model test, the fatigue damage of the bow structure of FPSO is analyzed, with emphasis on two points. One is the procedure and position selection for fatigue check, and the other is the application of new formulae for the calculation of accumulative fatigue damage caused by two sets of short-term distribution of hot spot stress range. From the results distinguished features of fatigue damage to the FPSOs bow structure can be observed.     

小型帆船自适应自动舵

帆船由于其结构的特殊使其动态特性呈严重的非线性，航向很难控制。首先针对一种小型竞赛用的12m长美洲杯赛帆船，从其结构出发建立数学模型，并对该模型进行了开环仿真试验以验证其真实程度。然后利用MATLAB辨识工具在不同的外部条件下得到各具特色的不同模型，由此确认模型参数的巨大变化难以用一个近似于当前运行模式下的线性化模型设计控制器，因而设计了一个采用自适应LQR的自动舵以控制帆船尖不同外部条件下都能保持航向。最后在该模型上作了仿真，取得了较好的效果。     

机舱运行参数控制系统中调节器参数的整定

利用开环频率特性对船舶机舱主要运行参数控制系统中调节器参数的计算整定进行了研究。同时介绍了几种常用的调节器参数工程整定的方法及其整定中的注意事项。     

地铁3.4 m线间距单渡线总体方案研究

研究目的:地铁建设项目利用既有双线隧道工程,由于限界限制,线间距只有3.4 m,如此小的线间距设置单渡线,国内外工程实例尚无,设置3.4m线间距单渡线可直接利用既有隧道工程,对盘活国有资产降低工程造价,有着重大意义。研究方法:研究道岔设计参数的制定原则,分析我国铁路道岔、城轨交通道岔设计参数的选用情况,确定合理的单渡线设计参数,进而对单渡线作安全性检算并选择合理的结构。研究结论:地铁采用3.4 m线间距单渡线。道岔选用的设计参数值,不低于两端单开道岔设计参数值,经过安全性检算,其容许通过速度为30 km/h时,地铁车辆行驶在单渡线时能保证行车安全及旅客舒适度。单渡线连接部分结构方案是合理的,给设计3.4 m线间距单渡线提供了可靠的支持。     

基于ISP技术的船舶自动化系统

介绍了在系统编程技术在船舶自动化系统中的应用,论述了具有在系统编程功能的船舶自动化系统设备层的一般性结构,对在船舶自动化系统设备层在系统编程技术的实现、大容量数据采集、存储和处理等技术问题,提出了具体的解决方案,并付诸实践。     

神经网络自适应控制算法的研究和MATLAB仿真

本文针对神经网络系统跟踪输入信号时,由于误差总是存在导致学习过程难以结束的特点,以一种用BP 网络逼近对象的学习算法为基础,结合相应的控制算法加以改进,并得到了一种快速学习因子的选择方法。结合不同对象通过MATLAB进行仿真,均获得了满意的效果。仿真和分析表明,该算法能保证系统具有良好的动态品质。     

二维CAD图纸快速转换成MARS模型的程序实现

通过VBA语言对CAD进行二次开发,将二维的CAD典型横剖面图纸信息导入MARS中实现快速建模。此程序可以从CAD图形中自动读取外板、甲板和纵骨的坐标信息,将其输出至xml文件中,而后只需稍作修改便可完成MARS建模工作。其中外板的处理是难点,需要在表示外板的样条曲线(或圆弧)中插入细密的节点,将其转化为直线多段线,从而准确模拟原曲线的形状,然后在满足精度的条件下过滤多余节点,只提取有效节点的坐标信息。该程序可辅助计算剖面模数,有效提高工作效率。