首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
介绍了盘式制动器混合多目标优化问题数学模型的建立,提出以制动摩擦力矩和制动时间为主要优化目标的多目标函数,为求得全局最优解,引进了遗传算法进行优化,结果表明,方法简便可行。  相似文献   

2.
本文主要论述了影响气压盘式制动器制动力矩大小的几个主要因素,及各因素对制动器性能带来的影响。通过理论计算和有限元软件的应用,对比几种增大制动力的方式,确定合适的增加ADB制动力矩的方法,并将其应用于实际产品开发。  相似文献   

3.
It is quite challenging to estimate the braking performance of a vehicle because the brake system is comprised of many parts, including a booster, master cylinder, and caliper. Calculation of characteristics such as braking force through vehicle tests requires much time and money. Therefore, the development of a method to estimate the braking performance of a vehicle using qualitative methods is beneficial. In this study, a program that can analyze the braking capabilities of a vehicle such as pressure, efficiency, and pedal travel is presented. The increase in disc temperature during braking as well as the properties of various boosters can be calculated using the proposed program. Dynamic characteristics of a vehicle equipped with a Load Sensing Proportional Valve (LSPV) were computed more precisely by obtaining the change in valve pressure according to the displacement of a suspension system. Since all input and output files are composed in the Microsoft Excel format, both design data management and database construction can easily completed.  相似文献   

4.
黄勇 《客车技术》2014,(5):21-24
为满足整车制动性能要求,对主机厂提供的参数进行制动力匹配计算,并将计算结果与试验结果进行对比,其制动性能试验结果符合法规GB 12676—1999的相关要求。  相似文献   

5.
Emergency brake technologies have always been a major interest of vehicle active safety-related studies. On homogeneous surfaces, traditional anti-lock brake system (ABS) can achieve efficient braking performance and maintain the handling capability as well. However, when road conditions are time variant during the braking process, or different at the bilateral wheels, braking stability performance is likely to be degraded. To address this problem and enhance ABS performances, a practical identifier of road variations is developed in this study. The proposed identifier adopts a statechart-based approach and is hierarchically constructed with a wheel layer and a full vehicle layer identifier. Based on the identification results, modifications are made to a four-phase wheel-behaviour-based ABS controller to enhance its performance. The feasibility and effectiveness of the proposed identifier in collaborating with the modified ABS controller are examined via simulations and further validated by track tests under various practical braking scenarios.  相似文献   

6.
工程机械ECU检修方法   总被引:4,自引:0,他引:4  
针对ECU常见故障,结合工程机械使用条件,分析了故障机理,探讨了故障诊断方法,提出了检修要点。结果表明,9种检测诊断方法操作简便、可行,在检修过程中加以合理采用可以对ECU的故障进行有效诊断。  相似文献   

7.
Brake judder is abnormal vibration, which is mainly generated by uneven contact between the brake disc and pad. The abnormal vibration from BTV (Brake Torque Variation) is transferred to the suspension and the steering system during braking. In this paper, judder simulation is carried out using a multi-body dynamic analysis program to analyze the relationship between judder and the transfer mechanism, which consists of the suspension and the steering system. In order to verify the analytical model, test results are compared with the simulation results. A sensitivity analysis is also carried out. In addition, an optimization method is presented for judder reduction, using the design of experiments.  相似文献   

8.
An enhanced parametric model for a copper-layered eddy current electric machine (retarder) is introduced in this paper. The modeled torque characteristics of the copper-layered electromagnetic retarders are based on the results from a detailed electromagnetic finite element analysis (FEA) of these eddy current machines. The model uses a parameterized double-exponential function to model the steady state speed-torque characteristics of the retarder. The parameters are adjusted for optimal braking performance in conjunction with predicted speed-torque characteristics of a copper-layered retarder. A full vehicle model, along with the proposed retarder speed-torque model has been used to simulate a series braking events. The simulation results show that the peaks of the retarder speed-torque curves must be designed to occur within a specific range of speeds for optimal braking performance.  相似文献   

9.
李强 《客车技术》2010,(2):14-16
制动系统热衰退是引发交通事故的一个重要原因。如何降低汽车持续制动时制动器的热衰退以保证车辆的行驶安全性是摆在人们面前的一个急需解决的问题。针对这个问题,在这里就车辆持续制动时,对制动特征、产生热衰退现象的机理及降低制动系统热衰退的措施等方而问题进行了深入探讨研究。  相似文献   

10.
An adaptive control algorithm was developed for the sensorless speed control of a permanent-magnet DC motor directly connected to the hydraulic pump of an antilock brake system. Due to the severe cost and reliability constraints of the application, the motor speed was controlled by a very simple on-off switching method, in which the only measurement required is the voltage across the control switch. The motor speed was calculated solely from the back-EMF voltage during the period of the control cycle when the switching controller is in the switch-off mode. The stability of the developed adaptiveswitching control algorithm was proven mathematically and confirmed experimentally in several vehicle tests over a wide range of target speeds and pump-load conditions. The accuracy and the response time of the controller can easily be tuned by adjusting a single tuning parameter. The switching frequency of the controller can also easily be tuned by adjusting the over-and undershoot thresholds independently from the accuracy of the speed-tracking control.  相似文献   

11.
随着高速公路的迅速发展和车速的提高以及车流密度的日益增大,为了保证行车安全,汽车制动系的工作可靠性显得日益重要。也只有制动性能良好、制动系工作可靠的汽车,才能充分发挥其动力性能。这里主要叙述中型客车制动系统的设计开发思路、主要制动参数的确认及校核、协调方法、试验的重要性。  相似文献   

12.
建立了某混合动力汽车控制器的热设计仿真分析模型,并通过温度测量试验验证了该模型的有效性。基于所建立的热设计模型,分析研究了控制器PCB板不同结构对其最大温升的影响程度。根据分析结果,推荐混合动力汽车控制器的PCB板应做成板厚为1.6 mm的4层板,覆铜面积和1oz的覆铜厚度应大于50%。  相似文献   

13.
分析发动机的起动回路,介绍几种常见的起动机ECU保护程序。通过采取这些保护措施,能有效地保护起动机,提高其使用寿命。  相似文献   

14.
邹立大 《汽车电器》2009,(12):27-31
简述加藤HD1430Ⅲ型挖掘机电控系统的概况,以图形、图表等形式详细阐述其电子控制装置(ECU)和相关部件的主要功能、工作特征、性能特点等。  相似文献   

15.
Designs and analyses of seat-suspension systems are invariably performed considering effective vertical spring rate and damping properties, while neglecting important contributions due to kinematics of the widely used cross-linkage mechanism. In this study, a kineto-dynamic model of a seat-suspension is formulated to obtain relations for effective vertical suspension stiffness and damping characteristics as functions of those of the air spring and the hydraulic damper, respectively. The proposed relations are verified through simulations of the multi-body dynamic model of the cross-linkage seat-suspension in the ADAMS platform. The validity of the kineto-dynamic model is also demonstrated through comparisons of its vibration transmission response with the experimental data. The model is used to identify optimal air spring coordinates to attain nearly constant natural frequency of the suspension, irrespective of the seated body mass and seated height. A methodology is further proposed to identify optimal damping requirements for vehicle-specific suspension designs to achieve minimal seat effective amplitude transmissibility (SEAT) and vibration dose value (VDV) considering vibration spectra of different classes of earthmoving vehicles. The shock and vibration isolation performance potentials of the optimal designs are evaluated under selected vehicle vibration superimposed with shock motions. Results show that the vehicle-specific optimal designs could provide substantial reductions in the SEAT and VDV values for the vehicle classes considered.  相似文献   

16.
The squeal noise occurring from the disc brakes of passenger cars has been analyzed by using the complex eigenvalue method numerically. The contact between a disc and two pads was analytically modeled as many linear springs and dampers in an effort to develop the improved equation of motion derived on the basis of Lagrange’s equation and the assumed mode method. The finite element modal analysis results for disc brake components constitute an eigenvalue matrix in the analytical equation of motion. The complex eigenvalue analyses based on the equations of motion are able to examine the dynamic instability of a brake system, which is an onset of squeal, by considering the disc rotational effect. Numerical analyses showed that the modes unstable in an undamped analysis became stable in a damped case, which illustrates the important effect of damping on the squeal instability in a brake squeal simulation. Then several modified brake models were suggested and investigated how effectively they suppressed the occurrence of squeal noise. The brake parts such as a pad chamfer and a disc vane were modified and the influence of pad chamfer and vane shapes on squeal occurrence was proved to be significant. The numerical results showed that proper structural modification of a disc brake system can suppress the brake squeal to some extent.  相似文献   

17.
This paper investigates the brake corner system to reduce brake torque variation in the brake judder problem. A numerical model for determining brake torque variation was constructed using the multi-body dynamics model. Using this model, the brake torque variation for a given disc thickness variation was obtained in the time domain. The multi-body dynamics model was verified by a dynamometer test via the comparison of brake torque variation and load distribution patterns of the pad. To reduce the simulation time and cost required to determine factors that influence the reduction in brake torque variation, a simple mathematical model was constructed and used to determine both the brake torque variation and influential factors. The multi-body dynamics model and dynamometer test were modified on the basis of the results of the simple mathematical model and deformed shape of the multi-body dynamics model. These influential factors were verified to reduce the brake torque variation.  相似文献   

18.
19.
5 506A型空调控制单元J293 零件号为357919506A的空调控制单元J293有30、1、2这3个大插脚和P、31、T2、T4、X、MK、T1和T这8个小插脚,比506、506B、506C等多了T、T1这2个小插脚。内部采用双面敷铜板固定着电风扇高速继电器J1、电风扇低速继电器J2和压缩机离合器继电器J3,每个继电器都由一个晶体管开关电路来控制它的线圈通路。此外还有一个集成块和几十个电子元件。  相似文献   

20.
柴油/乙醇双燃料客车发动机电控系统难题解决方案初探   总被引:1,自引:0,他引:1  
刘芳  熊锐  唐智 《城市车辆》2009,(1):43-45
本文首先对国内外柴油/乙醇双燃料发动机电控系统的研究现状进行了分析,提出了一种新颖的柴油/乙醇双燃料混合比的计算机实时控制方法,通过实时检测发动机工况,利用单片机控制柴油机循环供油量所需乙醇的喷射量,使发动机在各种工况下的空气、柴油和乙醇能够按最佳混合比进行燃烧。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号