Comparison of All-Wheel Steerings in the System Driver-Vehicle

SUMMARY

Different load or tires and a drive on an ice-coated road can overcharge a driver to such an extend, that the result may be an accident. Therefore the aim of development is a self-acting compensation of the vehicle to different vehicle transfer behaviour (invariant vehicle behaviour).

The calculation of so called optimal characteristics shows, that only rear-wheel steering cannot realize this aim of development. Therefore an additional front-wheel angle, which is not influenced by the driver, is necessary. A transfer function can be calculated in order to get controlled steering of the rear wheels without the influence of load.

It is not possible to realize optimal characteristics, because the parameters of the vehicle are difficult to measure. Only an optimal diagnosis and control of driving condition realize a relief for the driver in every driving situation in order to avoid most of the accidents.

The often demanded sideslip angle compensation only worsens driving conditions on ice-coated roads. Therefore systems which identify the driving condition themselves have to be favoured in any case.     

Dynamic Identification of Driver-Vehicle System Using AR-method

SUMMARY

When investigating dynamics of a driver-vehicle system, isolation between driver dynamics and vehicle dynamics becomes important, because interaction between them exists in the closed-loop system. The subject of this study is to examine effectiveness of AR-method by which each dynamics can be identified. The AR-method applied to lane changes, usually having rather short duration data, provides usefullness for the isolation. This method well reflects variation of subject drivers in identified results, and time series data recoverd by identified VAR-model is consistent with field data.     

Dynamic Identification of Driver-Vehicle System Using AR-method

When investigating dynamics of a driver-vehicle system, isolation between driver dynamics and vehicle dynamics becomes important, because interaction between them exists in the closed-loop system. The subject of this study is to examine effectiveness of AR-method by which each dynamics can be identified. The AR-method applied to lane changes, usually having rather short duration data, provides usefullness for the isolation. This method well reflects variation of subject drivers in identified results, and time series data recoverd by identified VAR-model is consistent with field data.     

Handling Safety Simulation of Driver-Vehicle Closed-Loop System with Evolutionary Random Road Input

The response simulation is studied and the handling safety is evaluated using finer integration method for driver-vehicle closed-loop system with stationary random road input. This algorithm is not only precise, but can also shorten the evaluation period of handling safety and reduce the tremendous cost for real vehicle testing. The response simulation and the vehicle handling safety evaluation are also studied for the closed-loop system with evolutionary random road input. The study can more truly simulate vehicle handling quality for including the varying of vehicle velocity with time.     

Handling Safety Simulation of Driver-Vehicle Closed-Loop System with Evolutionary Random Road Input

The response simulation is studied and the handling safety is evaluated using finer integration method for driver-vehicle closed-loop system with stationary random road input. This algorithm is not only precise, but can also shorten the evaluation period of handling safety and reduce the tremendous cost for real vehicle testing. The response simulation and the vehicle handling safety evaluation are also studied for the closed-loop system with evolutionary random road input. The study can more truly simulate vehicle handling quality for including the varying of vehicle velocity with time.     

Sensitivity of Driver-Vehicle Performance to Vehicle Characteristics Revealed in Open-loop Tests

The advantages of being able to objectively specify desirable vehicle handling characteristics, which can be determined without recourse to closed-loop tests on a prototype vehicle, are widely recognised. This paper reviews the studies that have attempted to find a relationship between closed-loop task performance, and driver subjective opinion, and various steady-state and transient characteristics revealed in open-loop tests of the vehicle. It is found that the level of definition of these relationships is not sufficient to justify mandatory regulations for vehicle design. However, the basic requirements for steering control sensitivity, and the rapidity and stability of the fixed-control dynamic response of vehicles in normal manoeuvres, are beginning to emerge. Data are particularly lacking for the closed-loop effects of vehicle sideslipping characteristics, free-control responses and vehicle behaviour in limit manoeuvres.     

燃料电池汽车正向建模及人车闭环仿真

应用Matlab/Simulink建立了燃料电池汽车正向模型,描述了从人车控制界面的车辆动力控制部件开始,控制机械转矩发生装置产生转矩,沿转矩传递路线直至车轮使车辆前进的过程;而速度跟踪的纵向驾驶员模型,描述了驾驶员驾驶车辆按给定目标速度行驶的模型.对车辆正向模型与纵向驾驶员模型组成的人车闭环模型进行仿真与试验数据对比表明,该模型准确性高.可对任意给定的循环工况进行仿真.     

全轮独立电驱动车辆双重转向控制策略的研究

为全轮独立电驱动车辆提出一种双重转向的控制策略,设计了双重转向的总体控制结构.它是包括三自由度参考车辆模型、横摆力矩确定层和转矩分配层的分层控制体系.在横摆力矩确定层中,设计了基于PID的横摆力矩控制策略;在转矩分配层中,设计了基于纵向驱动力总和不变的转矩分配策略.在此基础上,开发了双重转向控制策略仿真平台,进行了仿真分析和实车试验,试验结果与仿真结果吻合度较高,表明所提出的双重转向控制策略对减小车辆转向半径有明显效果.     

柴油机涡轮增压系统的比较与优选

本文基于模糊集理论,建立了柴油机增压系统方案的比较与优选模型,用解析化和数量化的手段辅助设计师对涡轮增压系统方案进行合理的比较与优选,通过示例说明了所建立模型的可行性。     

翼滑艇推进系统模糊控制的仿真比较研究

在Matlab平台上，设计了基于模糊逻辑工具箱的模糊控制器和规则自动拟合模糊控制器；建立了翼滑艇的智能推进系统模型，并用Matlab／Sireulink编制了仿真模型；进行了实时仿真。仿真结果表明：规则自动拟合模糊控制器，无论是从超调量方面还是从稳定性方面，都比工具箱的模糊控制器的控制效果好。     

重卡提升桥控制系统对比及应用

提升桥的使用,可减轻车辆的自重,降低油耗,减少轮胎的磨损,能为用户带来良好的经济效益。由于通过气囊将提升桥提升,气囊具有良好的非线性弹性特性,用于车辆悬架装置中可以明显改善车辆的操纵稳定性和行驶平顺性,同时可以减轻重载车辆对路面的破坏,在重卡上得到广泛的应用。本文对提升桥悬架结构形式进行简述,对比分析了目前几种提升桥控制系统各自优缺点。     

盾构推进液压系统控制模式的分析比较

盾构为隧道施工的重大技术装备,推进系统性能的好坏直接影响盾构姿态、施工开挖隧道线路的精准度以及掘进速度。盾构在软弱地层的施工过程中,某些盾构容易出现姿态控制困难及"栽头"现象,文章通过对不同厂家推进系统控制模式进行研究及原因分析,从理论上与实际监测进行比较得出结论。就目前国内外盾构产品而言,推进液压系统控制模式主要有2种,比例压力流量复合控制方案和比例减压阀控制方案,通过AMESim仿真、理论分析,并结合现场的实际监测数据比较了2种控制模式下执行机构动态响应特性,从而对盾构的可操作性及姿态控制特性进行分析比较,以期对推进液压系统的设计及盾构的选型、使用有一定的参考价值。     

汽车前碰撞预警系统测试法规的对比解析

汽车前碰撞预警系统(Forward Collision Warning System,FCWS)可以显著降低追尾事故发生风险,为了加强测试法规的认知,本文对比分析了JT/T 883-2014、GB/T 33577-2017以及韩国KC TEST关于FCWS的测试标准及理论依据,解析了测试法规涉及的测试参数确定的原因。分析结果表明:各法规的测试方法类似,但指标有所差异;JT/T 883-2014关于碰撞时间(Time-to-Collision)的设置更为保守;GB/T 33577-2017以及韩国KC TEST关于TTC的设置类似,但KC TEST的标准从使用体验上更为严格合理;此外,当两车存在相对加速度时,考虑相对加速度变化的TTC计算是非常有必要的。     

大型桥梁健康监测系统中2种数据通信技术的应用及比较

Lonworks现场总线技术和基于TCP/IP的局域网(LAN)技术是目前用于构建桥梁健康监测系统的数据通信系统最为主流的2种技术.对这2项技术的原理进行了分析,并探讨了其在桥梁健康监测系统中的应用.     

大型桥梁健康监测系统中2种数据通信技术的应用及比较

Lonworks现场总线技术和基于TCP/IP的局域网（LAN）技术是目前用于构建桥梁健康监测系统的数据通信系统最为主流的2种技术.对这2项技术的原理进行了分析,并探讨了其在桥梁健康监测系统中的应用.     

V型墩刚构桥的空间受力分析与体系比选

以上海市奉贤区某跨运河全钢结构V型墩刚构桥为工程背景,利用通用有限元软件ANSYS建立空间板壳模型,对V型墩刚构桥的空间受力特点进行分析,并与常规杆系模型的计算结果进行比较,进而探讨了墩梁固结区受力特性;针对双幅箱梁间不同横梁设置参数,分析了双幅结构的竖向变形协调性等空间受力特性,提出了V型墩刚构桥的构造设计建议;对V墩与基础连接方式进行比选,从经济性、整体刚度等方面进行综合比较,选取合理的结构体系.     

城市渣土自卸汽车液压举升系统对比分析研究

介绍了目前国内渣土自卸车的使用工况,针对6m以下的自卸汽车,着重将配置了腹置连杆放大式举升系统和前置多级缸举升系统的渣土自卸车产品的工作效率、可靠性、稳定性、安全性、经济性等性能指标进行了对比分析,提出了腹置连杆放大式举升系统在城市渣土自卸汽车上的应用优势,为渣土自卸汽车生产企业及用户的合理选型提供了参考依据.     

成品料提升机控制系统设计方案的比较分析

针对沥青混合料搅拌设备中成品料提升机控制单元的设计问题,利用比较的方法,分析了斗车运行速度的控制策略及控制单元的硬件组成,给出了PLC和单片机控制系统的结构框图。分析指出了斗车运行以分段变速运行控制为佳,并说明了分别以PLC、单片机为基础组成硬件系统的各自优点。结论对从事搅拌设备控制系统设计和维修的人员具有一定的参考意义。