Dynamic modelling and experimental validation of three wheeled tilting vehicles

The present paper describes the study of the stability in the straight running of a three-wheeled tilting vehicle for urban and sub-urban mobility. The analysis was carried out by developing a multibody model in the Matlab/SimulinkSimMechanics environment. An Adams-Motorcycle model and an equivalent analytical model were developed for the cross-validation and for highlighting the similarities with the lateral dynamics of motorcycles. Field tests were carried out to validate the model and identify some critical parameters, such as the damping on the steering system. The stability analysis demonstrates that the lateral dynamic motions are characterised by vibration modes that are similar to that of a motorcycle. Additionally, it shows that the wobble mode is significantly affected by the castor trail, whereas it is only slightly affected by the dynamics of the front suspension. For the present case study, the frame compliance also has no influence on the weave and wobble.     

Performance of spade-less wheeled military vehicles with passive and semi-active suspensions during mortar firing

Many armies are replacing heavy slow tracked vehicles with their lighter wheeled counterparts for their high mobility and better shoot and scoot capabilities. These features make the vehicle hard to track and target in counter-battery fire. However, when firing high calibre guns, spades are needed to connect the vehicle chassis to the ground, so as to transmit parts of the large firing force directly to the ground. Use of spades hinders the vehicle mobility, while elimination of them paves the way for having quicker and more mobile wheeled vehicles. In this article, vibration response of a spade-less High Mobility Multi-purpose Wheeled Vehicle with a mounted mortar is studied and controlled using stock passive, optimised passive, and optimised semi-active dampers as primary suspensions. The spade-less vehicle with optimised passive and semi-active dampers has a better response in heave, pitch, and fore-aft motions and can fire with better accuracy compared to a spade-less vehicle with stock passive dampers. Simulation results indicate that the spades can be removed from wheeled military vehicles if the precautions are taken for the tyres.     

An investigation into the effect of suspension configurations on the performance of tracked vehicles traversing bump terrains

This is a theoretical investigation into the effect of various suspension configurations on a tracked vehicle performance over bump terrains. The model developed is validated using published experimental data of the modal characteristics of the vehicle. The desired performance is based on ride comfort via the mixed objective function (MOF), which combines the crest factor of bounce acceleration, bounce displacement, angular acceleration, and pitch angle. The optimisation process involves evaluating the MOF for different numbers and locations of dampers and under different rigid bump road conditions and speeds. The system responses of the selected suspension configurations in the time and frequency domains are compared against the undamped suspension. The results show that the suspension configurations have a significant effect on the vehicle mobility over bump road profiles. For a five-road–wheel half model of a tracked vehicle, the maximum number of dampers to use for ride comfort over these road bumps is three with the dampers located at wheel positions 1, 2 and 5. This confirms the current practice for many tracked vehicles with 10 road wheels. However, it is further shown that the suspension fitted with two dampers at the extreme road wheels offer the best performance over various rigid bump terrains.     

用于电动和混合动力交通工具的功率模块

对减少CO2排放的急迫呼吁,已使主要的汽车制造商致力于开发新的电动和混合动力驱动交通工具解决方案。为这些应用开发功率半导体模块,需要新的模块集成和封装解决方案。     

现代中高级轿车技术发展趋势

随着我国经济形势持续向好,人民生活水平稳步提高,私人购车需求正逐年增大。当今的中国消费者已变得越来越成熟,他们不仅知道:中级汽车看配备,高级汽车看技术;甚至还懂得:在购车时看“技术”的关键要看汽车的“三大件”,也就是发动机、底盘和变速箱,它们相当于人体的心脏、骨骼     

天然气汽车发展中的问题和对策分析

本文简要阐述了天然气汽车（NGV）的优势,分析了天然气汽车发展中存在的一些问题,提出了一些发展天然气汽车的具体建议和对策。     

重型汽车雨刮不工作故障排查

汽车雨刮系统是车辆安全运行的主要保障之一,本文主要介绍了重型汽车雨刮的组成工作原理及雨刮出现不工作故障的排查。     

正确选择和使用汽车润滑脂

阐述了汽车常用的通用润滑脂的品种、牌号、特性及适应范围和润滑脂的选择与使用，并对目前汽车使用润滑脂中普遍存在的问题进行了论述。     

低温环境对车辆使用的影响及对策

我国北方地区的车辆,受气候环境的影响,在使用过程中较容易出车辆起动困难和总成异常磨损。本文针分析了在低温环境下造成车辆起动困难和总成(尤其是发动机)异常磨损的主要原因,并提出了相应对策,旨在提高低温条件下车辆的使用水平。     

Performance optimization of CVT for two-wheeled vehicles

Continuously Variable Transmission (CVT) is one of the most promising automotive transmission technologies because of its continuously variable gear ratio and reduced shift shock. CVT is different from Manual Transmission and Automatic Transmission, and it is possible to operate the power source in its high efficiency region with CVT in the drive train. Several types of CVT exist that can be categorized based on the mechanism of power transmission, such as the belt pulley, traction drive, and hydrostatic types. This paper investigates the belt pulley CVT, which consists of a thrust actuator, driver pulley, belt, driven pulley, and preload spring of the output shaft. A complete CVT is constructed, and based on that a simulation program that analyzes the static performance of a CVT is implemented in Matlab/Simulink. From these simulation results, methods for improving the efficiency of the CVT are discussed. The coefficient of the torque capacity factor is proposed as affecting the matching between a power source and a CVT, and methods for improving the matching effect are also investigated.     

Lateral stability control of dynamic steering for dual motor drive high speed tracked vehicle

In this paper, the torque and power required by dual motors for electric tracked vehicle during dynamic steering maneuvers with different steering radiuses are analyzed. A steering coupling drive system composed of a new type of center steering motor, two Electromagnetic (EM) clutches, two planetary gear couplers, and two propulsion motors is proposed for the dual motors drive high speed electric tracked vehicle (2MHETV), which aims to improve its lateral stability. An average torque direct distribution control strategy based on steering coupling and an optimization-distribution-based close-loop control strategy are designed separately to control the driving torque or regenerative braking torque of two propulsion motors for vehicle stability enhancement. Then models of the 2MHETV and the proposed control strategy are established in Recudyn and Matlab/Simulink respectively to evaluate the lateral stability of dynamic steering for the 2MHETV with different steering radiuses on hard pavement.The simulation results show that the lateral stability of the 2MHETV can be significantly improved by the proposed optimization-distribution-based close-loop control strategy based on steering coupling system.     

影像人车生活

每到车展，各家企业的展台美人如云，且男女美人皆有，藉此吸引眼球，目前中国的车展也是人展，对于广大摄友，色友而言是必到的饕餮大餐，我们特种提出以下建议供广大摄友参考。     

东风商用车和天籁获多项殊荣

2004—2005年度中国汽车市场调查结果9月27日在天津“中国汽车产业发展国际论坛”颁布。根据调查结果所产生的十几个奖项花落有主。东风商用车以稳健的实力,将“2004—2005年度中国十大车型”、“2004—2005年度知名度高、美誉度好、质量过硬的中型载货汽车”奖项摘下;天籁则一     

Modeling and model predictive control for hybrid electric vehicles

This paper builds up a typical model of a parallel hybrid electric vehicle and develops model predictive controllers for this model to control the speeds and torques for fast clutch engagement with high driving comfort and low jerk. Some modified algorithms for model predictive controllers are studied to improve their ability to track the desired speed setpoints, subject to input and output constraints.     

重型汽车电动车窗的工作原理及故障排查

汽车电动车窗是驾驶室配置的重要组成部分,本文主要介绍了重型汽车上电动车窗的组成部分、工作原理及故障排查。     

混合动力电动汽车研究开发及前景展望

随着世界石油资源逐渐贫乏,寻求新能源已成为解决石油危机的必然选择.混合动力电动汽车应运时代的要求,逐步走向规模化和产业化.本文主要介绍混合动力电动汽车的不同种类车型的特点,并对混合动力电动汽车的发展作出了大胆的展望.     

Automatic control of clutches and simulations for parallel hybrid vehicles

This paper is a continuation of a previous paper titled ??Modeling and Model Predictive Control for Hybrid Vehicle?? published on IJAT/2011 describing a mathematical model and design for a model predictive controller for tracking speeds and simulations. The present paper further describes a fuzzy logic controller for the smooth and quick engagement of an automatic clutch. The described controller uses both fuzzy logic and slip control algorithms to enable automatic clutch engagement. Clutch engagement and comprehensive simulations for the hybrid vehicle are conducted in MATLAB R2009s. The research described herein offers theoretical solutions for how to better control clutch slip and engagement within realistic parameters used for hybrid vehicles. Algorithms and operations of this fuzzy logic controller can be implemented in electronic control units for automatic clutch engagements and gear-shifting processes.     

Robust control and actuator dynamics compensation for railway vehicles

A robust controller is designed for active steering of a high speed train bogie with solid axle wheel sets to reduce track irregularity effects on the vehicle’s dynamics and improve stability and curving performance. A half-car railway vehicle model with seven degrees of freedom equipped with practical accelerometers and angular velocity sensors is considered for the H_∞ control design. The controller is robust against the wheel/rail contact parameter variations. Field measurement data are used as the track irregularities in simulations. The control force is applied to the vehicle model via ball-screw electromechanical actuators. To compensate the actuator dynamics, the time delay is identified online and is used in a second-order polynomial extrapolation carried out to predict and modify the control command to the actuator. The performance of the proposed controller and actuator dynamics compensation technique are examined on a one-car railway vehicle model with realistic structural parameters and nonlinear wheel and rail profiles. The results showed that for the case of nonlinear wheel and rail profiles significant improvements in the active control performance can be achieved using the proposed compensation technique.