模糊逻辑控制系统研究

汽车倒车防撞系统在车辆倒车时利用模糊逻辑控制方式,通过安装在车身上的5个超声波探头测量汽车两侧及车尾与障碍物的距离,当车上装的探头与障碍物的距离大于设定的极限值发出声音报警,提醒驾驶员而实现安全倒车。本文介绍了超声波测距工作原理;并对汽车倒车系统进行仿真实验,通过仿真、实验验证了本系统的可行性和有效性。     

单片机控制的超声波测距仪汽车倒车系统的设计

本文设计一种基于单片机STC89C52的超声波测距仪汽车倒车系统,介绍了超声波测距的基本原理,阐述了倒车雷达系统的结构组成、硬件电路设计,并在数据处理部分采用温度补偿消除温度对声速的影响,提高了测距精度.倒车距离采用LCD进行实时显示,并通过语音报警电路对不同距离段做出不同的语音提示.实验表明该倒车雷达系统在30～ 5...     

基于超声波测距的汽车倒车报警器设计

详细介绍了一种超声波测距系统及根据该系统设计、研制的汽车倒车防撞测距报警器。它能在汽车倒车时自动检测并显示车尾与最近障碍物之间的距离。当到达安全极限距离时，它能发出声光报警，提醒司机刹车。另外，在倒车过程中它还能发出“倒车，请注意”的报警声提醒行人注意。     

汽车倒车防撞雷达系统原理及优化的探讨

文章概述了利用单片机控制的超声波测距应用于汽车倒车防撞雷达系统的基本原理,例如当汽车倒车时,启动单片机及外部传感器实现距离测量,单片机对超声波的发射与接收通过计时进行控制,当所测得的距离小于预设的安全距离时,启动声光报警,有效避开可能对倒车造成危害的障碍物和行人。同时文章对该系统存在的弊端及其优化思路进行详细阐述。     

基于Android的可视倒车系统设计

设计的可视倒车系统是在Android操作系统平台下,以三星公司的S3C6410作为处理器,利用OV9650摄像头对汽车尾部的实时路况信息进行采集,通过LCD显示屏直观的呈现出来,以语音报警系统和超声波测距作为辅助,完成整个可视倒车系统的软硬件设计,达到清晰显示倒车路况的同时,实现比较精确的测距和障碍物距离语音报警,克服倒车盲区。     

专车专用 完美匹配——丰田卡罗拉AVIC升级测试

银声在全视泊车基础上整合旗下资源,推出AVIC平台以来,迅速将AVIC系统推向市场,并再些基础上进一步整合和丰富了专车专用机的内涵。自2008年银声进一步挖掘和提升其全视泊车技术以来,其配备倒车辅助线功能的VD08也随之进入AVIC平台,目前市场上这类产品还属凤毛麟角,银声VD08智能倒车方向辅助系统加入了智能倒车辅助线,在启动后视场情况下,辅助线会随方向盘转动而预示和模拟倒车轨迹,加之车后两侧雷达可以分别计算距离障碍物距离,显示到主机屏幕上,这都让AVIC平台的倒车后视功能得到空前加强。     

汽车可视倒车雷达预警系统的设计与实现

针对汽车倒车时的后视不良引起的倒车事故,介绍了一种可视倒车雷达预警系统装置的设计方案;该系统在汽车挂倒挡时开始工作,通过超声波传感器发送超声波检测障碍物信息,经微处理器处理成测距信息,同时系统启动后视摄像系统,将汽车后视摄像信息与障碍物距离信息通过视频字符叠加处理后,发送到TFT_LCD屏驱动模块显示;当距离小到一定范围时,自动启动真人语音报警;该系统安装简单、抗震能力强、后视图像直观真实、测距准确且工作稳定可靠。     

Elmos推出带LIN的智能超声波倒车辅助系统芯片

艾尔默斯公司（Elraos）推出最新可用于驱动超声波传感器的E524．14数字智能超声波倒车辅助系统芯片。该芯片主要适用于汽车领域和工业领域,如汽车超声波倒车辅助系统、自动开启后备箱系统、BSD盲点侦测系统,在工业领域中的测距离、测液位及停车场测车位等应用。     

基于STM32和超声波测距的倒车雷达预警系统设计

针对目前大多数经济实用型汽车、货车等车辆没有装备倒车雷达的现状,设计出一种成本低、结构简单、可靠性高的倒车雷达预警系统.硬件设计主要包括超声波测距电路、单片机控制电路、LCD显示电路、报警电路等;软件设计主要包括超声波测距原理介绍和系统软件工作流程等.汽车倒车时,该系统能够检测出汽车后面障碍物的距离,并且在LCD上实时显示汽车与障碍物之间的距离;当障碍物与车之间的距离超出预先设定的报警距离时,该系统会发出声光报警,提高安全性.实验结果表明:该系统在20 ～500 cm范围内可实现准确测距,最大平均误差不超过3％,能够在预设的报警距离处及时报警,达到预期目的,具有经济实用、操作简单、性能好等优点.     

C-MBUS总线在倒车雷达系统中的应用

为减少汽车倒车时的碰撞事故,采用C-MBUS总线技术和超声波测距技术相结合的方法,设计了倒车雷达系统.该系统利用LCD显示车辆与障碍物的距离和大致方位,并根据实际结果,采用不同的语音进行提示,对不同频率的声音进行报警.该系统具有结构简单、精度高、成本低廉和可靠性强等优点,能够满足倒车时障碍物检测的需求.     

防控车辆追尾智能技术

针对驾驶员控制安全车距所存在的致命弱点,提出并建立一种车辆智能测算前后相邻车辆间距的智能装置与方法,实时控制车辆前后合理车距,因此能够有效避免车辆追尾或被追尾事故的发生。该项技术装置模块化,算法识别周期短,经实用证实系统具有较高运行可靠性。     

An intelligent driver location system for smart parking

It is often frustrating for drivers to find parking spaces, and parking itself is costly in almost every major city in the world. Here we propose a crowdsourcing solution by exploiting sensors in smart-phones to collect real-time parking availability information. We design a phone-based system to track a driver’s trajectory to detect when they are about to leave their parking spot. We focus on the efficiency and accuracy of using a phone to monitor the driver’s walking trajectory, applying a waist-mounted PDR method that can measure the driver’s moving distance with a high accuracy. In addition, we design a map matching algorithm to calibrate the direction errors when the driver is in an indoor environment, using widely-available building floor plans. The results of our experiment show that we can achieve about 98% accuracy in estimating the user’s walking distance, with an overall location error of about 0.48 m.     

Comparative evaluation of performance measures for human driving skills

In this paper, we evaluate the adequacy of several performance measures for the evaluation of driving skills between different drivers. This work was motivated by the need for a training system that captures the driving skills of an expert driver and transfers the skills to novice drivers using a haptic-enabled driving simulator. The performance measures examined include traditional task performance measures, e.g., the mean position error, and a stochastic distance between a pair of hidden Markov models (HMMs), each of which is trained for an individual driver. The emphasis of the latter is on the differences between the stochastic somatosensory processes of human driving skills. For the evaluation, we developed a driving simulator and carried out an experiment that collected the driving data of an expert driver whose data were used as a reference for comparison and of many other subjects. The performance measures were computed from the experimental data, and they were compared to each other. We also collected the subjective judgement scores of the driver’s skills made by a highly-experienced external evaluator, and these subjective scores were compared with the objective performance measures. Analysis results showed that the HMM-based distance metric had a moderately high correlation between the subjective scores and it was also consistent with the other task performance measures, indicating the adequacy of the HMM-based metric as an objective performance measure for driving skill learning. The findings of this work can contribute to developing a driving simulator for training with an objective assessment function of driving skills.     

Effects of arousing attention on distracted driver’s following behaviour under uncertainty

This paper proposes issuing alerts to arouse driver attention when the traffic situation ahead is uncertain. Here, “uncertain” means that there exist cues suggesting something is happening in traffic ahead, but it is unclear to the driver and the driver assistance system whether an emergency situation will really occur in the near future, because traffic ahead cannot be seen directly. In such a situation, the driver has to pay attention ahead to prepare a quick response in case an emergency occurs. An experiment with a high-fidelity driving simulator was conducted to investigate the effectiveness of an attention arousing system when the driver was distracted. The results showed that the attention arousing system contributed to increasing time headway (THW) to the lead vehicle, where THW is the headway distance divided by the host vehicle speed and is often used to evaluate the rear-end collision risk. Such safety compensating behaviour was observed not only under distracted conditions, but also under non-distracted conditions. However, the compensating behaviour was not excessive under non-distracted conditions. The attention arousing was effective to maintain safety when the lead vehicle decelerated rapidly. The reaction time was long when the drivers were performing a distracting task. However, because the drivers had increased THW beforehand when conducting the distracting secondary task, the delay in reaction did not worsen the situation.     

视觉测量中多光学靶点亮度自适应控制

提出了一种面向大视场高精度视觉测量的多红外目标靶点（红外LED）亮度自适应控制方法。以微控制器PIC16F873A和LED驱动芯片MAX6964作为核心器件,设计了可满足大空间范围内靶点亮度控制需求的多目标靶点控制驱动器。为了使LED在近距测量时的调节精度和远近距离测量时的发光亮度都能满足要求,根据MAX6964输出特点设计了PWM信号输出电路,并采用推挽电路驱动LED。实验证明,目标靶点在CCD相机上成像光斑稳定一致。     

基于机器视觉的轻量级驾驶辅助系统

为了解决计算机视觉应用中数据量大、算法复杂的问题,根据道路结构特征和车辆行为特征,采用单个摄像头作为传感器,实现了一种轻量级的安全辅助驾驶系统。首先采用改进的边缘提取算法和车道线检测算法对摄像机内外参数进行离线标定;接着根据标定结果在二维平面图像上采用标识出实际空间距离的多窗口划分方法,并按不同的车间距将不同窗口划分为不同安全系数的区域,以赋予道路视觉检测的几何先验知识;当区域中出现障碍物时发出相应警示信息进行安全驾驶辅助,能为智能辅助驾驶提供轻量级的视觉检测平台。以便携式计算机和固定在车内的摄像头作为实验装置,在城市道路上进行车载实验。系统在车载实验中能够快速地提取车辆两侧的车道线,并利用离线标定的结果快速生成不同安全系数的警示区域,其中车辆在车道内正常行驶时的误检率和漏检率很小,可以忽略不计。与传统的驾驶辅助系统相比,本系统计算量大大降低,检测流程得到简化,可实现轻量级的车道和车辆检测,为系统在嵌入式系统上的实现奠定基础。     

车辆远程监控系统的设计与实现

文章提出了一种具有实时安全预警功能的车辆远程监控系统,包括车载数据采集端、手机客户端以及监控中心.汽车车载数据采集终端可实时采集到车辆的位置信息、速度和加速度信息并通过3G无线通信网络将这些数据发送到监控中心数据服务器.监控中心接收到所有车辆传来的数据,并将信息发送到用户车的手机客户端上,手机客户端通过本车的数据和周边车辆的数据计算出本车是否处于安全状态,如不安全手机客户端则会预警,提醒驾驶员采取措施避免事故的发生.     

基于双霍尔传感器的磁性小球悬浮控制系统研究

本文设计并实现了一种基于双线性霍尔传感器结构的磁性小球悬浮控制系统,在电磁驱动器底端及顶端中心位置各同向布置一个线性霍尔传感器,通过传感器信号调理电路,将两路传感器的输出信号作减法处理,消除了电磁驱动器磁场对传感器输出信号的影响。试验表明,磁性小球到电磁驱动器底端距离为16.46~42.46 mm时,调理电路输出电压值与磁性小球到电磁驱动器底端距离的负三次方成正比。基于PID控制策略,设计了一个磁性小球悬浮控制系统,选取合适的PID控制器参数,试验表明,系统的超调量和响应速度能够符合设计要求,磁性小球实现了在25 mm位置处的稳定磁悬浮,系统的位置控制精度达到±0.125 mm。     

AVR单片机的全方位雷达辅助行车系统设计

针对4探头倒车雷达常存在视觉盲区造成停车困难的问题,本文研究一种包含8探头的全方位雷达辅助行车系统.8个探头分别布置在车头和车尾,在车辆前进和倒车状态下分别启用不同位置的雷达,通过AVR单片机控制电路模块、超声波测距模块、液晶显示模块、蜂鸣器报警模块等实现多路障碍物的探测、距离显示和声音报警功能,以帮助驾驶员判断车辆距离障碍物的远近,全面了解车辆周围情况.     

用Numega DriverStudio设计Windows NT设备驱动程序

WindowsNT以其高度安全性和全新体系结构，而成为许多应用系统的首选操作系统平台，开发WindowsNT下的驱动程序已成为应用系统开发的难点之一，本文简述了驱动程序的生成、调试、安装方法，系统介绍了用Numega DriverStudio设计WindowsNT的设备驱动程序，包括多板同机、驱动程序与应用程序的I／O通信和中断事件通知，在此基础上可以编写实用的WindowsNT设备驱动程序。