纯电动汽车动力驱动系统电动机的选择方法之研究

本文首先介绍了电动汽车用电动机的基本性能,并从汽车行驶动力学出发建立了纯电动汽车用电动机性能参数的数学模型,其次探讨总结了对电动机基本特性参数的初步确定原则。最后以目前所要开发的一辆纯电动汽车的基本参数及目标性能要求为例,按以上原则确定出电动机参数并绘制符合要求的电动机性能曲线,为电动机的快速选择和后续车辆动力传动系统匹配优化提供了依据。     

自动驾驶多传感器融合的时间校准方法研究

针对自动驾驶感知域系统的激光雷达、图像传感器、惯性测量单元3种传感器数据融合的时基校准问题,利用机械式激光雷达自身特征设计校准设备、系统及实验方法.基于激光雷达的触发事件和车载图像传感器感知特征,实现两种传感器时基在线标定,并通过示波器测量校验证明该方法的有效性.利用激光雷达扫描频率与触发事件时间差相互关联的特征,将激...     

Heavy vehicle pitch dynamics and suspension tuning. Part I: unconnected suspension

The influence of suspension tuning of passenger cars on bounce and pitch ride performance has been explored in a number of studies, while only minimal efforts have been made for establishing similar rules for heavy vehicles. This study aims to explore pitch dynamics and suspension tunings of a two-axle heavy vehicle with unconnected suspension, which could also provide valuable information for heavy vehicles with coupled suspensions. Based on a generalised pitch-plane model of a two-axle heavy vehicle integrating either unconnected or coupled suspension, three dimensionless measures of suspension properties are defined and analysed—namely the pitch margin (PM), pitch stiffness ratio (PSR), and coupled pitch stiffness ratio (CPSR)—for different unconnected suspension tunings and load conditions. Dynamic responses of the vehicle with three different load conditions and five different tunings of the unconnected suspension are obtained under excitations arising from three different random road roughness conditions and a wide range of driving speeds, and braking manoeuvres. The responses are evaluated in terms of performance measures related to vertical and pitch ride, dynamic tyre load, suspension travel, and pitch-attitude control characteristics of the vehicle. Fundamental relationships between the vehicle responses and the proposed suspension measures (PM, PSR, and CPSR) are established, based on which some basic suspension tuning rules for heavy vehicles with unconnected suspensions are also proposed.     

Hybrid state-feedback sliding-mode controller using fuzzy logic for four-wheel-steering vehicles

This paper presents a fuzzy controller for high-speed four-wheel-steering (4WS) vehicles based on the state-feedback and the sliding-mode control methods. In the proposed fuzzy controller, the consequent part of the fuzzy IF-THEN rules consists of either a sliding-mode controller or a state-feedback controller. Also, it will be proved that, if every fuzzy rule is stable in the sense of Lyapunov for a general Lyapunov function, defined for the whole system, then the whole system is stable in the sense of Lyapunov. The effectiveness of the proposed method for handling improvement of the 4WS systems will be demonstrated by simulations using a nonlinear vehicle model. The simulation results show that the proposed control method can enhance the dynamic response of the 4WS vehicles by reducing the transient response time and improving vehicle stability as compared to the sliding-mode and the fuzzy sliding-mode control methods.     

影响重型车油耗的发动机参数

随着油耗和排放法规的加严,控制重型车油耗将成为大势所趋。文章以一台柴油机为测试对象,研究了出水温度、进油温度及中冷后温度对其油耗测试结果的影响。试验结果表明,3个参数都不会对发动机油耗测量结果造成较大的偏差,其影响程度在可接受的误差范围内。在进行重型车油耗测试时,可以忽略上述发动机条件对其结果的影响。     

对新能源汽车发展的几点思考

为了研究新能源汽车发展，通过对传统能源和传统动力汽车现状的阐述，分析了新能源汽车发展的可能性。，在进行各国对新能源汽车政策分析的基础上，结合现阶段电动汽车动力电池的现状，对新能源汽车将来的发展趋势做了预测，在研究分析的基础上，对中国汽车工业的发展提出了建议，为研究新能源汽车发展的方向和汽车企业制定战略计划提供参考：     

Global force potential of over-actuated vehicles

This paper formulates force constraints of over-actuated road vehicles. In particular, focus is put on different vehicle configurations provided with electrical drivelines. It is demonstrated that a number of vehicles possesses non-convex tyre and actuator constraints, which have an impact on the way in which the actuators are to be used. By mapping the actuator forces to a space on a global level, the potential of the vehicle motion is investigated for the vehicles studied. It is concluded that vehicles with individual drive, compared with individual brakes only, have a great potential to yaw motion even under strong lateral acceleration.     

新能源汽车技术专业“小课时、多门数”课程实施的探究

自我国实施新能源电动汽车战略以来,新能源汽车数量持续快速增加,新能源汽车市场对新能源汽车相关专业人才的需求也急剧加大。新能源汽车市场急需懂专业、有素养、技术水平高的高素质人才服务新能源汽车市场的维护、营销等需要。新能源汽车是在传统汽车的基础上发展起来的,采用了新技术、新方法,技术路线复杂,涉及到计算机编程、高压、电池、维护、充电、电机、发动机等各方面的知识。相比传统汽车专业,新能源汽车技术专业需要学生在有限的校园生涯内掌握更多、更复杂的知识,需要学生学习的知识范围更广。采用"小课时、多门数"的课程设置可通过凝炼课程内容、精减单门课的课程学时、增加课程门数、扩展学生学习知识的广度,有效解决学生在有限的校园生涯内学习更多知识的问题,满足新能源汽车市场对复合型人才的需要。     

Efficiency of routing and scheduling system for small and medium size enterprises utilizing vehicle location data

The routing and scheduling for trucks and vans in an urban road network depends critically on the state of the road network. Trucks and vans impose significant costs on other road users and the environment, so improved routing and scheduling benefits more than just the logistics industry. However, small and medium size enterprises (SMEs) in the logistics business cannot justify investment in planning systems. In this paper, an autonomous routing and scheduling system which is available to SMEs is proposed and the efficiency of the system is investigated. The proposed system accumulates vehicle location data in a central server and uses it to generate traffic information. Test simulations using a grid network demonstrate the effects of utilizing and sharing vehicle location data on delivery efficiency. The simulation results show that the improvement of delivery efficiency is mainly due to the reduction of penalty cost for early and late arrival at the customer location. It is also shown that the system leads to the buffer effect from variations in traffic conditions on delivery cost and this effect is enhanced by taking travel time uncertainty into consideration. It is further shown that the presence of measurement periods with insufficient data results in unreliable routing and scheduling. For a reliable system, data collection over a wider area is required rather than dense data in a subset of links.     

共享无人驾驶交通系统调度技术综述

众多研究证明共享无人驾驶车辆（SAVs）交通系统，能够实现车辆完全可控并为乘客提供个性化服务，即克服导致共享单车大量倒闭的运维和调配难题，也可消除制约公交竞争力的准时性、舒适性、覆盖性差的不足，有望成为未来城市交通的主体出行模式之一，并在很大程度上解决交通拥堵、环境污染、能源紧缺等城市病。基于此，总结SAVs交通系统相对传统共享车辆系统在不同运行模式方面的优点及不足，综述SAVs交通系统的调度技术。从SAVs交通系统运行过程出发，总结并分析SAVs交通系统不同运行方式，包括SAVs交通系统出行需求产生方式、车辆与需求匹配方式、车辆路径规划与车辆再平衡方式，以及运行方式与系统参数发生变化时对车辆行驶里程、车辆行驶时间、车队规模、乘客等待时间和服务水平等系统性能的积极与消极影响。对现有成果的梳理发现对于SAVs交通系统运行与性能的研究虽然取得了很大进展，但对于选择SAVs的出行需求计算多未考虑需求转移的影响，能够有效在大型路网中使用的系统模型与算法依然缺乏，且对于SAVs交通系统的调度研究考虑的形式可以更加多样，使之更符合现实情况。最后，基于提高SAVs系统性能对未来研究方向进行了展望，提出一些可能的研究课题。研究成果可为SAVs交通系统的研究提供参考。