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 62 毫秒
1.
为实现智能车自动寻迹,研制一种基于汽车模型为硬件平台的智能车系统.传统PI控制的参数固定,难满足模型沿指定路径行驶的智能化要求;而模糊自适应PI控制具有控制精度高,控制灵活且适应性强的优点,可以精确、稳定的控制车速.路径信息采集模块将摄像头采集的道路信息传送至微处理器,微处理器输出合适控制量对舵机进行方向控制,同时综合编码器将测得的速度反馈给微处理器,采用模糊PI控制对智能车直流电机进行速度控制,该方案可以使智能车快速稳定的沿指定路径行驶.  相似文献   

2.
赵容晨  赵津 《贵州科学》2013,31(1):60-64,88
以飞思卡尔模型C车为车载平台,基于Adriano开发环境,采用红外线传感器进行路径检测,设计了一种寻线智能车.该智能车主要包括微控制器(MCU)模块、电机及驱动模块、舵机模块、路径识别模块.通过系统软、硬件的调试,小车能够稳定的沿引导轨迹运行,行驶效果良好,验证了系统设计可行性.  相似文献   

3.
针对真实道路上开展智能汽车研究存在的风险和困难,提出了一种基于缩微城市道路环境的智能车交互行为研究平台. 该平台首先实现了具备视觉认知功能的缩微智能车,采用了一种基于特征和模型融合的嵌入式平台实时车道线和障碍物检测算法,通过本车可行驶区域的形式化描述,实现道路环境的感知,最后经过模糊决策控制方法控制缩微智能车产生拟人驾驶行为. 实验结果表明,文中提出的研究平台能够有效模拟智能车车间交互行为,环境感知算法和决策控制方法能够满足实时性和精度要求.  相似文献   

4.
基于MC9S128的摄像头导航智能车的设计与实现   总被引:1,自引:0,他引:1  
介绍了一种基于摄像头导航的智能车系统设计方法.该系统根据全国大学生飞思卡尔杯智能汽车大赛的设计要求,使用飞思卡尔16位单片机MC9S 128为核心控制单元,设计了传感器、电源、电机驱动、车速检测等硬件电路;利用PID和模糊控制相结合的方式,使智能车能够自动采集、分析引导线信息,控制舵机转向,实现智能车的自动寻迹.  相似文献   

5.
基于CMOS摄像头的智能车控制系统设计及实现   总被引:1,自引:0,他引:1  
针对智能车因单条引导线信息量少而引起的误识别问题, 设计一种能自动识别和跟踪双边引导线的智能车系统。智能车以Freescale公司MC9S12XSl28作为核心控制器, 利用COMS(Complementary Metal Oxide Semiconductor)摄像头OV7620作为路径信息采集装置, 对采集图像进行二值化处理、 去噪操作和边缘检测后提取路径信息、 进而准确地判别跑道的形状, 为舵机和电机提供控制依据, 以使小车平稳快速地行驶。同时, 提出将行驶状态与赛道信息综合考虑的措施, 并通过PID(Proportional Integral Differential)控制策略以及实验测试, 实现了对各种典型跑道的优化处理, 使高速行进中的智能车具有良好的转向调节能力和加减速响应能力。智能车可以在以白色为底面颜色, 两边有黑色引导线的跑道上运行, 克服了因单条引导线信息量少而引起的误识别问题。  相似文献   

6.
路径识别和转向系统根据MCU处理CMOS采集的路面信息的结果,通过脉宽调制模块(PWM)控制舵机转向,进而实现智能车的路径自动识别或引导线识别功能,按照设定的路线进行自动循迹和转弯控制。通过硬件二值化或者软件的局部自适应阈值二值化,对采集的路面信息图像进行分割,数据计算处理,提取出路面中心位置,且计算出对于路面中心位置的偏离程度,确保了智能车路径识别传感信号的准确、稳定与快速。随着乘用车自动化、智能化程度的加深,该技术有很大应用空间。  相似文献   

7.
许伟  沈捷  顾雪梅  胡彬 《科技信息》2011,(12):25-26
以地面引导线中的交变磁场信号(导航信号)为研究对象,选择电感作为主要部件,结合滤波放大电路构成导航信号的基本检测单元。为检测车体与引导线的距离偏差,布置两个基本检测单元以车体中线为对称轴,呈一字型分布于智能车前端左右两侧,将车体与引导线的距离偏差转化为左右检测单元之间的电压偏差,为智能车跟踪控制奠定基础。实践证明,该传感器模块为智能车准确跟踪引导线提供了有力保障。  相似文献   

8.
介绍了一种基于线阵CCD两轮自平衡的智能车循迹系统。基于第八届飞思卡尔智能车大赛准则,该系统以飞思卡尔16位单片机MC9S12XS128作为核心控制器,以CCD作为路径识别装置检测路径信息,通过陀螺仪与加速度计测量智能车姿态,单片机获得传感器采集的路面信息及智能车姿态信息,经过分析后控制智能车的舵机转向,同时对直流电机进行调速,从而实现智能车自平衡和速度调节。在控制算法上采用模糊设定速度和PID调整速度相结合的算法,使智能车能够在自平衡状态下快速平稳的行驶。  相似文献   

9.
介绍了一种基于Freescale公司的16位HCS12单片机的一种智能车控制系统,它采用黑白CMOS摄像头作为路径识别装置,通过图像识别提取路径信息.利用单片机产生PWM波,控制小车速度和转向,利用自制的速度传感器来获取小车当前速度,实现速度的闭环控制,增加小车的稳定性,较之常规的光电传感器识别路径方案,利用摄像头传感器可以获取更多的路径信息.测试结果表明,智能车能按任意给定的黑色引导线更能以较快的速度平稳地运行.  相似文献   

10.
智能车是可以自动识别道路并以最短时间行驶全程的一种无人驾驶汽车.路径识别跟踪技术和快速、稳定的控制策略是智能车发展的重要标志.给出以OV7620作为智能车的主传感器,以红外对管作为辅助传感器对赛道的信息进行采集.OV7620把赛道的亮暗程度转化成像素的灰度值,采用边沿跟踪检测图像处理算法.采用PID与bang-bang算法相结合的算法对智能车进行速度控制.实验表明智能车可以实现任意路径识别与智能快速行驶.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  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