Control effects of steer-by-wire system for motorcycles on lane-keeping performance

This study discusses the control effects of the steer-by-wire (SBW) system for motorcycles on the lane-keeping performance by examining computer simulation with a rider-vehicle system which consists of a simplified vehicle model, a rider control model and the controller of the SBW system. The SBW system, which compensates the rolling angle deviation between the desired rolling angle intended by the rider and the actual rolling angle, improves the lane-keeping performance of the rider-vehicle system under the steering torque disturbance. The SBW system is, on the other hand, not effective in the lane-keeping performance under the lateral force disturbance. In addition, the lane-keeping assistance (LKA) system is applied to the SBW system and the cooperativeness of the SBW and the LKA systems is examined. The LKA system improves the lane-keeping performance of the SBW system under not only the steering torque disturbance but also the lateral force disturbance.     

道路交叉口车路协调实验系统设计与实现

提出了道路交叉口车路协调实验系统框架、实现方法并进行了系统搭建测试。在分析系统功能的基础上进行了系统逻辑框架与系统物理框架设计,实现了各子系统功能,包括：GPS车载定位信息采集、交通控制系统设定、路侧处理单元与车载处理单元程序设计与短程无线通信,在此基础上建立了道路交叉口车路协调实验系统,模拟实际交通运行状态对系统主要性能进行测试。实验结果表明该系统可以完成信号灯状态的车载实时显示,但应进一步提高定位精度与通信效果。实验系统不仅为进一步研究基于车路协调的下一代智能交通运输系统提供了实验平台,还能采集相关的车辆运行数据与驾驶员特征数据。     

基于车载微机的混合动力汽车监测与诊断系统研究

以某混合动力轿车为研究对象，开展了基于车载微机的混合动力汽车监测与诊断系统的研究，在介绍了该系统用途以及相对于传统的基于CAN总线的监测系统优点的基础上，对系统的硬件设计、软件设计和系统功能进行了详细阐述，并利用仿真网络环境埘系统进行了测试，最终将其应用于某混合动力汽车上．     

燃料电池发动机测试系统开发

主要设计了一套燃料电池发动机测试系统,同时对燃料电池发动机动态特性测试方法进行了研究.燃料电池发动机测试系统包括PLC控制系统、辅助电源系统、氢气供给系统、电子负载系统、被测试发动机系统五个部分.加载方式可采用恒流加载和恒功率加载等多种方式,可以实现燃料电池发动机的起动特性、稳态特性、动态响应特性和循环工况运行等多种性...     

基于3G移动通信网络的长江航标船远程监测系统

介绍了一种基于3G移动通信网络航标船的远程监测系统,拟覆盖全长江航道上的所有航标船,实现机务和作业参数的远程传输和实时监视。提出了包括船载监测系统OMS、船岸通信系统MCS和机务中心实时监视和分析系统MCS共3大部分的总体方案;介绍了总体的设计原则和具体的系统设计;给出了总体系统图和软硬件配置列表。     

Advanced Steering System Adaptable to Lateral Control Task and Driver's Intention

This paper proposes an advanced steering system that adaptively varies the static gain and dynamics of the steering system. The steering system gain is adjusted, depending on whether the driver is in an aggressive or leisurely driving mood. The steering system dynamics is so designed that the command mode of the steering system will be either a rate-command or an attitude-command according to the lateral control task performed by the driver. The recognition system for lateral control tasks, a lane-following or lane-change task is proposed. The findings of simulator tests indicate proposed advanced steering system would remarkably improve the vehicle handling qualities.     

Hardware-in-the-loop simulation experiment for semi-active vibration control of lateral vibrations of railway vehicle by magneto-rheological fluid damper

The active lateral suspension (ALS) of a train consists of either active or semi-active technologies. However, such an active system on a real railway vehicle is not easy to test because of cost and time. In this study, a hardware-in-the-loop simulation (HILS) system is developed to test the ALS. To this end, the dynamic model of a railway vehicle is equipped with the actuator, two bogies and four-wheel sets, and the ALS is used. The proposed HILS system consists of an alternating current servo motor connected to a ball-screw mechanism and a digital control system. The digital control system implements the dynamic model and the control algorithm. The design and manufacture of the HILS system are explained in detail. Both the passive damper and the magneto-rheological (MR) fluid damper are tested using the HILS system, where the sky-hook control algorithm was applied for the MR fluid damper. Experimental results show that the proposed HILS system can be effectively used for the performance estimation of the ALS.     

某空间螺旋塔斜拉桥合理结构体系研究

某斜拉桥方案采用反对称螺旋形桥塔,空间四索面,造型较为新颖。由于桥梁结构较为复杂,为选用适宜的结构体系,基于桥梁结构的受力形态,在综合比较了漂浮体系、半漂浮体系、半固结体系的优劣后,确定半漂浮体系为最佳方案,并进一步讨论了地震作用下该桥合理的约束体系。这一流程对解决类似复杂结构桥梁合理结构体系的问题有一定参考价值。     

Experimental studies on the heating performance of the PTC heater and heat pump combined system in fuel cells and electric vehicles

In this study, a combined system consisting of a heat pump and a PTC heater was developed as a heating unit in electric vehicles. The system consists of a compressor, a condenser, an evaporator, an expansion device and a PTC heater. Experiments were conducted to examine the steady-state performance and dynamic characteristics of this system. The compressor speed, outdoor air inlet temperature, and indoor air inlet temperature were varied, and the performance of the system was experimentally investigated. The heating capacity, compressor power consumption and COP were obtained. Warm-up experiments were performed to investigate the dynamic characteristics of the system with a heat load of 1.5 kW in the indoor chamber. For the heat pump system, the PTC heater and the combined system, the heating performance and efficiency were investigated to determine an optimal control method. The results of this study agree well with the experimental results available in literature. This study provides experimental data of good quality for heating system design and the development of electric vehicles.     

Load-leveling suspension system with a magnetorheological damper

In this paper, a load-leveling suspension system with a magnetorheological (MR) damper is investigated. In this suspension system, the MR damper is connected to a spring to form a load-leveling suspension system. The system effective stiffness and damping can be adjusted by controlling the MR damper. The characteristics of a load-leveling suspension system are studied first. When the linear damper is replaced with an MR damper, the averaging method is adopted to obtain the steady-state response of the nonlinear system. A comparison demonstrates that the results of the averaging method are in good agreement with those obtained by numerical simulations. The analytical results are then verified experimentally. The load-leveling suspension system studied here is able to adjust both suspension stiffness and damping and, hence, it may provide more effective vibration control in a wider frequency range, when the damper is controlled.     

Load-leveling suspension system with a magnetorheological damper

In this paper, a load-leveling suspension system with a magnetorheological (MR) damper is investigated. In this suspension system, the MR damper is connected to a spring to form a load-leveling suspension system. The system effective stiffness and damping can be adjusted by controlling the MR damper. The characteristics of a load-leveling suspension system are studied first. When the linear damper is replaced with an MR damper, the averaging method is adopted to obtain the steady-state response of the nonlinear system. A comparison demonstrates that the results of the averaging method are in good agreement with those obtained by numerical simulations. The analytical results are then verified experimentally. The load-leveling suspension system studied here is able to adjust both suspension stiffness and damping and, hence, it may provide more effective vibration control in a wider frequency range, when the damper is controlled.     

车辆机械转向系统的使用与维护

车辆的转向系统是车辆组成的重要部分,转向系统可以对车的安全性起到直接影响,如果说机械转向系统发生故障,就很容易导致安全事故的发生。通常情况下,车辆机械转向系统出现问题的主要原因都是在车辆使用时,机械转向系统的零部件之间出现了摩擦。本文作者将会根据以往的自身实际经验,以及车辆工作的原理,探讨如何维护和使用车辆机械转向系统的有效方式,对详细说明给予研究,为车辆机械转向系统的正确使用提供参考和借鉴。     

Advanced Steering System Adaptable to Lateral Control Task and Driver's Intention

This paper proposes an advanced steering system that adaptively varies the static gain and dynamics of the steering system. The steering system gain is adjusted, depending on whether the driver is in an aggressive or leisurely driving mood. The steering system dynamics is so designed that the command mode of the steering system will be either a rate-command or an attitude-command according to the lateral control task performed by the driver. The recognition system for lateral control tasks, a lane-following or lane-change task is proposed. The findings of simulator tests indicate proposed advanced steering system would remarkably improve the vehicle handling qualities.     

On the feasibility of the optical steering wheel sensor: Modeling and control

This paper discusses the development of a system model for the wireless steering wheel angle sensor and steering wheel system for the evaluation of the steer by wire system in a vehicle dynamic system. The steering wheel sensor is a wireless, contact-less sensor utilizing an optical medium for angle detection. The optical medium is operated based on a photodiode and photo-detector head. A reflecting disc or code-wheel, working similar to a compact disc, is used to reflect the light from the photodiode back to the photo-detector. The beam is reflected based on the content in the reflective disc to measure the relative angle through a micro-controller. The proposed wireless steering sensor and steer by wire system is modeled using the Matlab/Simulink and their performance is investigated to evaluate the steering response, vehicle dynamics, and steering feel of the system. Finally, the feasibility of the proposed system is discussed based on the developed model and simulation results.     

Combined control of a regenerative braking and antilock braking system for hybrid electric vehicles

Most parallel hybrid electric vehicles (HEV) employ both a hydraulic braking system and a regenerative braking system to provide enhanced braking performance and energy regeneration. A new design of a combined braking control strategy (CBCS) is presented in this paper. The design is based on a new method of HEV braking torque distribution that makes the hydraulic braking system work together with the regenerative braking system. The control system meets the requirements of a vehicle longitudinal braking performance and gets more regenerative energy charge back to the battery. In the described system, a logic threshold control strategy (LTCS) is developed to adjust the hydraulic braking torque dynamically, and a fuzzy logic control strategy (FCS) is applied to adjust the regenerative braking torque dynamically. With the control strategy, the hydraulic braking system and the regenerative braking system work synchronously to assure high regenerative efficiency and good braking performance, even on roads with a low adhesion coefficient when emergency braking is required. The proposed braking control strategy is steady and effective, as demonstrated by the experiment and the simulation.     

大型桥梁健康监测系统的数据采集子系统设计方法

针对大型桥梁结构健康监测系统具有传感器类型多、信噪比小等特点,系统研究大型桥梁结构健康监测系统的数据采集子系统的设计方法。首先分析桥梁结构健康监测所采用的传感器的输出信号特征、输出信息量特征和空间分布特征;在此基础上,研究数据采集子系统的设计内容和原则,以及硬件、软件和基于网络的设计方法;最后,采用该设计方法为滨州黄河公路大桥健康监测系统设计了数据采集子系统。系统的运行表明,文章建立的设计方法是可行的。     

A real-time impact detection and diagnosis system of catenary using measured strains by fibre Bragg grating sensors

This paper describes an impact detection system using strain signals based on fibre optic sensors(FBG) for the real-time monitoring of the catenary system. The proposed detection system consists of three subsystems: a measuring system, a data processing and analysis system, and a status display and data access system. Because the strain signals obey the normal distribution, to monitor the catenary system in real time, a novel method that combines mobile standard deviation with the mobile Pauta criterion is proposed to distinguish real impact from the strain signal background. The use of this adaptive judging method reduces the misjudgment rate of impacts and improves the impact recognition accuracy. These impacts can be identified by the data analysis system, which provides impact location and their causes using the features of the catenary system. This method can simplify the detection system compared with the traditional location method. An application to a commercial metro line system indicated that the impacts on the catenary system were main caused by overlaps, expansion joints or steady arms, and were verified by correspondence with the floor plan of the catenary and manual inspection results. These results verified the reliability and effectiveness of the proposed impact detection system.     

发动机EGR和VNT执行器系统仿真

真空执行器大量应用于EGR和VNT系统,为改善空气系统控制效果,研究了一种EGR和VNT执行器系统模型。该模型包括空气系统与机械执行器系统两个主要部分:前者可采用孔口节流方程模拟,其开度函数可通过MAP图获得以简化模型;后者可视为“质量——弹簧”系统。试验结果表明,该模型能精确地模拟快变和慢变控制过程,可用于发动机空气系统建模及其控制算法,为该类系统的商业化应用奠定了基础。     

二甲醚燃料供给系统研究现状及发展趋势

摘要：介绍了国内外二甲醚发动机燃料供给系统研究概况,包括油泵一油管一油嘴系统和共轨式燃料供给系统。二甲醚粘度低导致燃油供给系统磨损和泄漏是二甲醚发动机实用化面临的主要问题。针对可控预混合燃烧二甲醚发动机开发的一种用隔膜泵、磨损自补偿喷油器或者独立润滑喷油器构成的燃料喷射系统,有望从本质上解决上述问题,成为未来的一个发展方向。     

国际汽车电子技术发展新动态——42V汽车供电系统

汽车电子控制技术和智能化的发展趋势，使得汽车电子附件所占的比例和相应耗电量大幅提高，现有12V供电系统对汽车未来产品的供电能力不足是汽车业提出高电压供电系统的直接原因。使用42V供电系统可对发动机、电动制动系统、电动离合器、电动动力转向系统、线束开关和连接器等的技术创新起到推动作用。