基于87C196KC单片机实现ABS轮速信号采集处理

本文介绍了87C196KC单片机高速输入部件HSI的中断功能以及在ABS轮速信号采集中的应用。设计了轮速信号采集系统的软硬件．提出一种基于频率法和周期法的ABS轮速采集算法，并分析了该算法的实时性。通过单片机在线仿真实验。结果证明了硬件设计和软件算法的正确性。     

车辆ABS数据采集系统设计

本文介绍ABS系统控制原理、基本组成,并通过设计数据采集系统采集ABS实时信号,来判断ABS效能的好坏。     

nRF24L01在ABS试验平台上的应用

介绍了无线通信模块NRF24L01的结构和特点,设计无线通信的ABS参数测量系统,系统通过对ABS试验平台轮速进行采集,将轮速转化成频率信号,利用周期测量法测出频率,经无线通信模块NRF24L0将数据发送出去。在终端通信模块与主接收模块之间采用TDMA通信方式进行数据交互,主接收模块接收到数据传送到上位机上显示。     

ABS轮速信号室内再现方法的研究

为满足ABS台架试验的需要．提出了采用伺服电机控制齿圈的运动以再现轮速信号的方法。采用实车ABS系统的齿圈和轮速传感器，将需要再现的实际轮速信号编程下载到运动控制器中，再控制伺服驱动器驱动电机带动齿圈转动，获得所需轮速信号。台架试验表明，所设计试验装置生成的轮速信号曲线与设定的ABS控制过程中轮速曲线符合得较好，满足ABS疲劳寿命台架试验和ABS控制器功能测试等对轮速信号的需要。     

基于MC9S12DP256B的客车ABS控制器设计

介绍了ABS控制器的硬件电路部分,给出了ABS控制算法。控制器算法采用逻辑门限值控制算法,轮速信号的处理采用修正的脉冲计数法,提高了计算精度。算法中引入五个中断,第一个中断用来采集轮速信号,后四个中断用来自实现四个轮子的ABS控制。以半实物仿真的形式对设计的控制器进行了验证,并给出了仿真结果,取得了较好的控制效果。     

一种新的ABS轮速处理方法研究

进入单片机的ABS原始轮速信号,不仅可能混入畸变信号,而且叠加了高频信号。利用此原始轮速信号来控制ABS,可能导致ABS电磁阀误动作。本文综合运用周期法和频率法,先用软件剔除信号中的畸变信号,之后采用滤波加拟合的方法计算轮速及其角加速度,并以此作为控制依据。ABS实车道路实验结果表明,上述方法计算得到的车轮角加速度波动较小,能够作为控制输入并满足控制的实时性要求。     

基于OSEKturbo操作系统的ABS控制系统

汽车防抱死制动系统简称ABS,ABS的工作原理是通过装在车上的传感器,感知制动轮每一瞬间的运动状态和行驶中轮胎与路面的摩擦。因为ABS对实时性的要求非常高,故主要讨论汽车ABS控制系统的原理与实现。系统采用了16位单片机MC9S12DP256,并移植了OSEKturbo OS,来满足ABS对实时性的要求。     

基于微处理器的ABS轮速信号采集处理系统的实现

采用8位及16位微处理器已经在很多场合下不能满足我们的性能需求，尤其汽车的制动系统的实时性要求．使得采用能够充分并且合理利用CPU的高性能32位微处理器成为设计汽车电控单元的趋势，设计了轮速信号采集系统的软硬件，提出了一种ABS轮速采集的算法，并分析了该算法的实时性;通过仿真实验。证明了硬件设计和软件算法的正确性以及系统的稳定性和实时性。     

32通道无线表面肌电和加速度信号采集系统设计

为满足对肌电信号采集系统无创、便携、更大传输数据量的需求。本文实现了基于蓝牙无线传输协议的32通道肌电和加速度信号采集系统。系统发送端由4组8通道信号采集发送模块组成,完成对表面肌电信号和加速度信号的采集、处理及发送;接收端采用FPGA管理4组蓝牙接收端进行一对一数据接收,同时完成对数据进行统一打包处理并发送到PC机进行数据存储、数据处理及信号波形显示。经测试,本系统一次充电可持续工作6小时,无线通信距离12m,信号噪声比高于70dB。测试结果表明,本系统可应用于手势识别、健康监护等领域。     

U-Boot在MicroBlaze处理器上的移植方法

在通信干扰系统中,为了分析干扰效果,通常需要对被干扰的信号进行采集和分析。由于文中所涉及的采集系统使用了Linux操作系统,因此需要用Bootloader（引导加载程序）将操作系统加载到采集系统的程序存储器,使系统投入运行。文中主要研究了该信号采集系统的Bootloader（U-Boot）的移植过程,针对采集系统所使用的硬件修改了U-Boot代码的文件,给出了U-Boot在移植过程中的详细步骤和修改要点,并对U-Boot启动后的采集系统进行了验证。结果表明,文中所移植的U-Boot程序可以正确引导Linux操作系统,并且能够提供操作系统所需参数,解决了该数据采集系统的操作系统无法加载的问题。文中的工作不仅为FPGA器件在嵌入式系统中的应用提供了一个较好的解决方案,同时文中所述的移植过程为相关的嵌入式系统设计人员提供了一定的参考。     

基于linux嵌入式系统的研究

从linux操作系统,嵌入式系统,采用linux作为嵌入式系统的原因,linux嵌入式系统的组成,linux嵌入式系统开发平台和开发环境五个方面对linux嵌入式系统进行了较深入研究.在此基础上,根据863计划,以及当前国家对自主操作系统的大力支持,指出了开发linux嵌入式系统的必要性.     

Evaluation of antilock braking system with an integrated model of full vehicle system dynamics

Antilock braking system (ABS), traction control system, etc. are used in modern automobiles for enhanced safety and reliability. Autonomous ABS system can take over the traction control of the vehicle either completely or partially. An antilock braking system using an on–off control strategy to maintain the wheel slip within a predefined range is studied here. The controller design needs integration with the vehicle dynamics model. A single wheel or a bicycle vehicle model considers only constant normal loading on the wheels. On the other hand, a four wheel vehicle model that accounts for dynamic normal loading on the wheels and generates correct lateral forces is suitable for reliable brake system design. This paper describes an integrated vehicle braking system dynamics and control modeling procedure for a four wheel vehicle. The vehicle system comprises several energy domains. The interdisciplinary modeling technique called bond graph is used to integrate models in different energy domains and control systems. The bond graph model of the integrated vehicle dynamic system is developed in a modular and hierarchical modeling environment and is simulated to evaluate the performance of the ABS system under various operating conditions.     

Evaluation of antilock braking system with an integrated model of full vehicle system dynamics

Antilock braking system (ABS), traction control system, etc. are used in modern automobiles for enhanced safety and reliability. Autonomous ABS system can take over the traction control of the vehicle either completely or partially. An antilock braking system using an on–off control strategy to maintain the wheel slip within a predefined range is studied here. The controller design needs integration with the vehicle dynamics model. A single wheel or a bicycle vehicle model considers only constant normal loading on the wheels. On the other hand, a four wheel vehicle model that accounts for dynamic normal loading on the wheels and generates correct lateral forces is suitable for reliable brake system design. This paper describes an integrated vehicle braking system dynamics and control modeling procedure for a four wheel vehicle. The vehicle system comprises several energy domains. The interdisciplinary modeling technique called bond graph is used to integrate models in different energy domains and control systems. The bond graph model of the integrated vehicle dynamic system is developed in a modular and hierarchical modeling environment and is simulated to evaluate the performance of the ABS system under various operating conditions.     

基于PXA270的嵌入式Linux系统移植构建

介绍了嵌入式系统体系结构、Linux系统移植原理及嵌入式Linux系统的构成。以In-tel PXA270处理器为例,阐述了嵌入式Linux系统移植构建的主要过程,包括开发环境的建立、Bootloader的定制与移植、Linux内核的裁剪与移植、根文件系统的制作与移植及系统调试等方面。     

Linux 系统在S3C2440 上移植的分析与实现

在分析Linux系统结构的基础上,描述了将完整的Linux系统向S3C2440平台上移植的关键步骤和过程,并详细介绍了如何建立属于自己的交叉编译环境和制作一个纯yaffs2文件系统的方法.经过对Bootloader、内核以及根文件系统的编译和烧写,实验结果表明,本文采取的方法,成功地实现了一个Linux系统向S3C2440平台上的移植.     

基于模糊控制的汽车防抱制动系统仿真

汽车防抱制动系统(ABS)通过在制动过程中自动控制车轮的制动力矩从而防止了车轮抱死。这对于提高汽车制动时的方向稳定性和转向操纵性，改善汽车的制动效能，保证驾驶员和乘客的安全是十分重要的。文中通过对某轻型客车的防抱制动过程进行动力学分析，建立了该轻型客车ABS模糊控制系统的数学模型，并且在Matlab／simullnk仿真软件下进行了计算机仿真。仿真结果表明，模糊控制的防抱制动系统能取得较好的控制效果，具有一定的自适应能力。     

Designing a genetic neural fuzzy antilock-brake-system controller

A typical antilock brake system (ABS) senses when the wheel lockup is to occur, releases the brakes momentarily, and then reapplies the brakes when the wheel spins up again. In this paper, a genetic neural fuzzy ABS controller is proposed that consists of a nonderivative neural optimizer and fuzzy-logic components (FLCs). The nonderivative optimizer finds the optimal wheel slips that maximize the road adhesion coefficient. The optimal wheel slips are for the front and rear wheels. The inputs to the FLC are the optimal wheel slips obtained by the nonderivative optimizer. The fuzzy components then compute brake torques that force the actual wheel slips to track the optimal wheel slips; these torques minimize the vehicle stopping distance. The FLCs are tuned using a genetic algorithm. The performance of the proposed controller is compared with the case when maximal brake torques are applied causing a wheel lockup, and with the case when wheel slips are kept constant while the road surface changes     

A novel method for non-linear control of wheel slip in anti-lock braking systems

Anti-lock braking system (ABS) provides active safety for vehicles during braking by regulation of the wheel slip at its optimum value. Due to the non-linear characteristics and model uncertainties in vehicle dynamics, a non-linear controller with increased robustness should be designed for ABS. In this paper, to achieve this aim, an optimization-based braking torque control law is developed for ABS using the prediction of the wheel slip response from a continuous non-linear vehicle dynamics model. To increase the robustness of the controller, the integral feedback technique is appended to the design method. The derived control law and its special cases are evaluated and discussed. At the end, the performance of the proposed controller is compared with that of a sliding mode controller, reported in the literature, through simulations of braking on dry and slippery roads. The simulation results indicate that, the wheel slip tracking error is remarkably decreased by the proposed controller. Moreover, the achieved control input is entirely smooth and suitable for implementation.