悬架K＆C试验台在底盘开发中的技术应用

简要介绍了国内悬架K＆C试验台的应用及发展情况,详细探讨了悬架K＆C试验台及其在底盘开发调校中的应用,阐述了悬架K＆C特性研究的作用及其必要性,以及所研究的主要内容。     

TECHNICAL NOTE

This paper presents an advanced control method in application of automotive systems. An adaptive fuzzy logic controller based on self tuning control methodology has been implemented and used to control the vehicle velocity. Fuzzy rules and reasoning are utilized on-line to determine the throttle angle, spark advance and braking force. Simulated results, as presented in this paper show the adaptive fuzzy control is well suited for vehicle speed control with a nonlinear dynamic behaviour of the engine.     

High precision A/F control ECU for ultra low emission vehicles

High precision A/F electronic control, which is an application of modern control technology, has played a special role as a ULEV emissions reduction technology. Observer theory has been used to compensate for variations in the air/fuel ratio between cylinders, and self tuning regulators have been used to control transient conditions and disturbances. These innovations have led to improvements in control performance.In order to implement these controls, the CPU must be capable of high speed computation. Thus RISC microcomputers for automotive use, which provide high speed computation in a small chip size, have been developed to replace conventional CISC microcomputers. This RISC chip has been used in our ULEV control ECU to provide high precision A/F control.     

乘用车操稳转向性能指标分解技术应用研究

车辆动力学性能开发包括性能目标设定、目标分解、优化设计、底盘调校,逐渐向目标达成逼近,开发结束后实现目标达成。性能目标分解即指标分解,用简单有物理意义的理论公式关联整车指标与总成指标,将整车的客观性能指标分解至系统特性,是整车性能目标达成的关键环节,在性能开发中承上启下,是各主机厂的核心技术。性能指标分解正常在车辆开发初期,用于指标分解的模型应采用尽可能少的建模参数,建模分析迅速且模型能明确表达系统参数对整车性能的影响规律。ADAMS或CarSim模型,由于模型结构过于复杂,不适用于车辆性能的指标分解。本文建立了用于性能指标分解的模型,并基于此模型研究底盘动力学操稳转向性能指标的分解及应用方法,为车辆动力学性能开发工作提供理论指导。     

变截面悬架稳定杆刚度计算与分析研究

以汽车变截面悬架稳定杆为研究对象,基于卡氏定理推导了该类型悬架稳定杆扭转刚度计算公式,并与CAE仿真分析结果进行对比,结果表明两者吻合良好。基于文中推导的扭转刚度计算方法,以某型实际车辆稳定杆为例,分析并研究了空间安装角、过渡区圆角半径、中间部位杆径及长度对扭转刚度的影响规律。最后结合实际底盘调试工作,提出了一种可快速改变稳定杆扭转刚度的改制方案,降低了调试成本并提升了调试效率。     

一种斜拉桥目标状态索力快速精准确定的方法

为了精准高效地确定斜拉桥目标状态索力,提出一种新型快速精准调索方法。该方法实施步骤为:计入结构的几何非线性效应,对斜拉索施加一定初张力确定计算初态;在计算初态基础上设定斜拉索的索力增量作为主调向量,通过逐次轮换主调向量进行有限元计算,相比计算初态确定关心截面内力或位移的增量效应矩阵及边界矩阵等参量;利用数值优化理论,建立约束条件及目标优化函数求解出满足要求的最优索力。以主跨518 m的荆岳铁路公安长江特大斜拉桥为工程实例,对该桥成桥状态、施工过程子目标状态的索力进行优化并对施工监控误差进行修正。结果表明:优化后的结构状态均满足工程要求,该调索方法具有快速、高效、精准等优点,可推广至斜拉桥、拱桥等成桥状态和施工过程控制子目标状态的索力确定,并为施工监控索力调整等提供了一种新的解决途径。     

液体质量双调谐减振器(TLMD)研究与应用

为解决调谐质量阻尼器(TMD)普遍存在的耐久性及参数调谐困难等问题,基于理论及试验研究,在TMD的基础上,利用调谐液体阻尼器(TLD)的优点,研发了新型液体质量双调谐减振器(TLMD)。TLMD减振器是TMD和TLD减振器的复合体,由于流体与固体的耦合作用,TLMD有比两者组合更好的减振效果。TLMD减振器应用于南京大胜关长江大桥吊杆涡振的振动控制中,实桥试验结果显示,在模态质量比仅为8‰左右时,所有被测吊杆的阻尼比均在3.2%以上,个别吊杆甚至达到4.66%,减振效果显著。     

XL纯电动轿车CAN总线系统及应用层协议的开发

为了满足XL纯电动轿车控制实时性和可靠性要求，提出了基于CAN总线的分布式控制系统拓扑结构，开发的CAN总线应用层协议，包括通信内容、ID编码、数据编码、数据格式、消息调度以及底层接口定义等6部分。文中还介绍了所开发的基于CAN总线的硬件在环测试系统。通过硬件在环测试、台架联合调试和道路试验对CAN总线系统进行综合实测和评价。实际运行表明，纯电动汽车CAN总线系统具有较高的可靠性和实时性。     

滨德互通立交设计方案比选

滨德互通立交是滨(州)德(州)高速公路与济南至乐陵高速公路相交的重要节点,介绍了滨德互通立交各转向交通量的分配,阐述了滨德互通立交各方案的设计思路及优缺点,并从立体布局、转向交通量、服务水平、公路用地、工程规模及造价方面进行比选,得出了最终设计方案。     

Fundamental Issues in Suspension Design for Heavy Road Vehicles

Heavy road vehicles play an important role in the economy of many countries by providing an efficient means of transporting freight. Such vehicles can also have a significant impact on safety, the infrastructure and the environment. The design of the suspension affects the performance of the vehicle in terms of ride, infrastructure damage, suspension working space, energy consumption, rollover stability, yaw stability, braking and traction. The published literature on suspension design for heavy road vehicles is reviewed. It is found that extensive knowledge exists, but that there are areas where improved understanding is needed. Areas identified as fundamental issues requiring attention include ride discomfort criteria, secondary suspensions, and controllable suspensions. Two issues in particular are examined in detail: suspension tuning and suspension configuration. In the tuning of suspension parameter values for vibration performance, numerical optimisation techniques have been used extensively, but generic tuning strategies have not been widely developed. Modal analysis is proposed as a technique for gaining the insight into vehicle vibration behaviour necessary to enable tuning strategies to be devised. As an example, the technique is applied to the pitch-plane vibration of a tractor-semitrailer. In analyses of new suspension configurations or concepts, comparison with alternative concepts is not always made. Lack of such comparisons makes the selection of an optimum concept difficult. Analysis of alternative concepts using simple mathematical models, and comparison of their performance using common criteria, is advocated for enabling informed selection of an optimum. An example involving two alternative roll control systems is used to demonstrate the issue.     

Application of Sensitivity Analysis to the Development of High Performance Adaptive Hydraulic Engine Mounts

Summary In this paper, the sensitivity analysis is applied to the development of high performance adaptive hydraulic mounts. The analysis allows us to select the most effective design parameters for tuning an adaptive mount to different road and engine conditions. It is shown that in the low frequency road excitation, the upper chamber compliance and inertia of the fluid column in the inertia track are the most influential properties in changing the dynamic stiffness of the hydraulic mount. These properties for the high frequency engine excitations are the upper compliance and the inertia of the fluid column of the decoupler. For tuning the adaptive mount to different road and engine excitation, a global optimization technique is used to find the magnitude of the adjusting parameters to minimize objective functions in low and high frequency excitations. The results indicate significant improvement over conventional hydraulic mounts. It is further shown that when the upper compliance is used as the adjusting parameter, a simple on-off control which is triggered by the engine revolution and vehicle speed is sufficient for tuning the adaptive mount.     

某乘用车平顺性调校及虚拟验证研究

基于某乘用车前期平顺性目标设定与分解,详细地介绍了其平顺性调校的方法和过程,运用主观评价手段对车辆的平顺性进行了调校,并对调校前后的参数指标建立了动力学虚拟样机。利用仿真方法展开定性验证,结果表明车辆平顺性在调校后满足前期平顺性目标,为底盘调校及悬架设计提供了较好的工程参考。     

Application of Sensitivity Analysis to the Development of High Performance Adaptive Hydraulic Engine Mounts

Summary In this paper, the sensitivity analysis is applied to the development of high performance adaptive hydraulic mounts. The analysis allows us to select the most effective design parameters for tuning an adaptive mount to different road and engine conditions. It is shown that in the low frequency road excitation, the upper chamber compliance and inertia of the fluid column in the inertia track are the most influential properties in changing the dynamic stiffness of the hydraulic mount. These properties for the high frequency engine excitations are the upper compliance and the inertia of the fluid column of the decoupler. For tuning the adaptive mount to different road and engine excitation, a global optimization technique is used to find the magnitude of the adjusting parameters to minimize objective functions in low and high frequency excitations. The results indicate significant improvement over conventional hydraulic mounts. It is further shown that when the upper compliance is used as the adjusting parameter, a simple on-off control which is triggered by the engine revolution and vehicle speed is sufficient for tuning the adaptive mount.     

Fundamental Issues in Suspension Design for Heavy Road Vehicles

Heavy road vehicles play an important role in the economy of many countries by providing an efficient means of transporting freight. Such vehicles can also have a significant impact on safety, the infrastructure and the environment. The design of the suspension affects the performance of the vehicle in terms of ride, infrastructure damage, suspension working space, energy consumption, rollover stability, yaw stability, braking and traction. The published literature on suspension design for heavy road vehicles is reviewed. It is found that extensive knowledge exists, but that there are areas where improved understanding is needed. Areas identified as fundamental issues requiring attention include ride discomfort criteria, secondary suspensions, and controllable suspensions. Two issues in particular are examined in detail: suspension tuning and suspension configuration. In the tuning of suspension parameter values for vibration performance, numerical optimisation techniques have been used extensively, but generic tuning strategies have not been widely developed. Modal analysis is proposed as a technique for gaining the insight into vehicle vibration behaviour necessary to enable tuning strategies to be devised. As an example, the technique is applied to the pitch-plane vibration of a tractor-semitrailer. In analyses of new suspension configurations or concepts, comparison with alternative concepts is not always made. Lack of such comparisons makes the selection of an optimum concept difficult. Analysis of alternative concepts using simple mathematical models, and comparison of their performance using common criteria, is advocated for enabling informed selection of an optimum. An example involving two alternative roll control systems is used to demonstrate the issue.     

Optimisation of nonlinear motion cueing algorithm based on genetic algorithm

Motion cueing algorithms (MCAs) are playing a significant role in driving simulators, aiming to deliver the most accurate human sensation to the simulator drivers compared with a real vehicle driver, without exceeding the physical limitations of the simulator. This paper provides the optimisation design of an MCA for a vehicle simulator, in order to find the most suitable washout algorithm parameters, while respecting all motion platform physical limitations, and minimising human perception error between real and simulator driver. One of the main limitations of the classical washout filters is that it is attuned by the worst-case scenario tuning method. This is based on trial and error, and is effected by driving and programmers experience, making this the most significant obstacle to full motion platform utilisation. This leads to inflexibility of the structure, production of false cues and makes the resulting simulator fail to suit all circumstances. In addition, the classical method does not take minimisation of human perception error and physical constraints into account. Production of motion cues and the impact of different parameters of classical washout filters on motion cues remain inaccessible for designers for this reason. The aim of this paper is to provide an optimisation method for tuning the MCA parameters, based on nonlinear filtering and genetic algorithms. This is done by taking vestibular sensation error into account between real and simulated cases, as well as main dynamic limitations, tilt coordination and correlation coefficient. Three additional compensatory linear blocks are integrated into the MCA, to be tuned in order to modify the performance of the filters successfully. The proposed optimised MCA is implemented in MATLAB/Simulink software packages. The results generated using the proposed method show increased performance in terms of human sensation, reference shape tracking and exploiting the platform more efficiently without reaching the motion limitations.     

模糊PID控制器在机油冷却器检测中的应用

通过利用参数整定PID的模糊控制器对发动机机油冷却器传热性能试验台的温度进行控制。利用模糊控制算法对PID3个参数k_p,k_i,k_d进行整定,以改善其控制性能,并根据实际系统进行仿真。结果表明,此系统能提高温度控制性能,提高了工作效率,简化了操作规程。     

可调弹簧刚度的空气悬架

从舒适性到动力性,这种新型悬架技术显著加大了悬架调整的选择范围,保证跑车在具备乘坐舒适性和驾驶安全性的同时,满足动力性的要求。     

Analysis and optimization of air suspension system with independent height and stiffness tuning

Suspensions play a crucial role in vehicle comfort and handling. Different types of suspensions have been proposed to address essential comfort and handling requirements of vehicles. The conventional air suspension systems use a single flexible rubber airbag to transfer the chassis load to the wheels. In this type of air suspensions, the chassis height can be controlled by further inflating the airbag; however, the suspension stiffness is not controllable, and it depends on the airbag volume and chassis load. A recent development in a new air suspension includes two air chambers (rubber airbags), allowing independent ride height and stiffness tuning. In this air suspension system, stiffness and ride height of the vehicle can be simultaneously altered for different driving conditions by controlling the air pressure in the two air chambers. This allows the vehicle’s natural frequency and height to be adjusted according to the load and road conditions. This article discusses optimization of an air suspension design with ride height and stiffness tuning. An analytical formulation is developed to yield the optimum design of the new air suspension system. Experimental results verify the mathematical modeling and show the advantages of the new air suspension system.     

车辆悬架的最优自适应与自校正控制

本文研究了车辆主动悬架自适应与自校正控制的策略与算法。