无人驾驶入门--Autoware使用手册
无人驾驶汽车系统入门 - Autoware_UsersManual_v1.1Autoware-用于城市自主驾驶的集成开源软件,支持以下功能:3D本地化3D映射路径规划路径跟随加速/制动/转向控制数据记录汽车/行人/物体检测交通信号检测交通灯识别车道检测对象跟踪传感器校准传感器融合面向云的地图连接自动化智能手机导航软件仿真虚拟现实Autoware受BSD许可证保护。请自行负责使用。为了安全使用,我们为不拥有真正自主车辆的人提供基于ROSBAG的仿真方法。如果您使用Autoware与真正的自主车辆,请在现场测试之前制定安全措施和风险评估。工尹-刁一定義亡机飞求世。Chapter1。 About This documentThis chapter describes the purpose of this document.Autoware Users ManualAutoware Developers manualChapter2。 RoS and AutowareBefore operating Autoware, RoS and Autoware are described in this chapter.Robot middleware- rosecently, the wide range potential of robotics has been focused by not only roboticsexperts but also non-robotics experts to join robot development It is believed thatthis trend leads robotics to advancement and developments to other domainsHowever, robot development is getting harder because the advancement and the complexityof robot functions have been increased Unlike Pcs and smartphones robotic developmenthas considered various hardware, OS, programming languages. Hence, the differences havemainly been obstructed for robotic developers as well as robotics experts to join robotdevelopmentTo solve the problem, the demand of making common platforms has been increased, andsome platforms have been published Within a common platform, developers can combinevarious software published by other developers, and speed up development by reusing themTherefore, it is expected that developers can more focus on fields of interestROS (Robot Operating System) is a framework for robotic software development. It wasdeveloped by Willow Garage in U.S. OSFR (Open Source Robotics Foundation) has currentlymaintained it. The open sourced ros has mainly been used by communities in U.S. andEurope as well as communities in JapanNote that ros has "os" in its name however, it is not "os" like Windows or linux. It is amiddleware that runs on uniX based OSROS FeaturesOriginal build system(Catkin)mage processing library(OpenCvv Data logging tool (ROSBAG)v Visualization tools for data and software state(rvizCoordinate transformation library (TFQt based gul development tool (RQTA""file is used to start multiple nodes atAutowareutoware is open source software based on ros. autoware is pushed on github forautonomous driving research and development. Most of autonomous drivingsystem consist of recognition, judgment, and operation. Autoware providesnecessary functions, such as 3-D map generation, localization, object recognition, andvehicle control, for autonomous drivingROS PCAutoware〔Ros)RecognitionJudgmentoperationObject DetectionLane KeepingAcceleratorLocalizationIntersectionBrakeSteeringAutowareRiderAutoware routePath PlanningVehicleVehicle control(CAN)CFigure 1 Autoware overviewwhile support systems such as driving assistance and safetydiagnosis support, use multi-core CPU3-D Map Generation and SharingLocalization(NDT: Normal Distributions Transform)object DetectionPath GenerationAutonomous Drivingtarget speed. In addition, the route includes landmarks, "way point, setintervals. The autonomous driving system operates path following by following the wayUser InterfaceA user interface called " Runtime Manager ofpath following. Furthermore, a tablet user interface, "Autoware Rider, of Autoware enablesROS PCAutoware(ROS)Runtime ManagerVIZAutoware ridertabletDisplay on vehicleOculusFigure 2 User interfacePlatform structure for autowareApplicationAutowareMiddlewareROSHost OsLinux( UbuntuCPUGPUCameraGNSSLIDARFigure 3 Platform structure for Autoware
- 2021-05-07下载
- 积分:1
大气湍流模型_.pdf
激光(Laser:Light Amplification by Stimulated Emission of Radiation)是光受激辐射放大的简称。原子受光子照射时不仅发生受激辐射同时还发生受激吸收。这两种过程是矛盾的。通常情况下吸收过程是主要的,受激辐射过程是次要的. 如果能够通过某种方法破坏粒子数的热平衡分布,受激辐射能量将大于吸收能量,受激过程将胜于吸收过程。这里E[v2]是单位为(m/s)2的速度平方平均值,离开地面高度h的单位为km,h的范围5~20km。近期实验证实了这个模型的近似合理性,并指出在儿百米以卜的近地面范围内,在白天Cn(h)≈C2()h43,在仅晚C2(h)≈C2()h23,另外Hal!发现8在草地覆盖面上空,Cn(h)≈C2()h3, Davidson发现海面上空C(h)≈C2()h23,1m≤h≤10m。一般m言,在近地面处C2的典型值从102m23(对于强湍流)到108m23(对于弱湍流)的范围内折射率功率谱密度折射率的随机起伏n1(r)主要是由温度空间分布中的随机微观结构而引起的,这种微观结构的起源则在于地球表面不同区域被太阳不同加热而引起的极大尺度的温度非均匀性,这种大尺度的温度非均匀性进而又引起大尺度的折射率非均匀性,它们最后被湍流风和对流冲碎,使非均匀性的尺度变得越来越小。湍流的大小范围通常从几毫米到几米,分别用内长度l和外长度L表示通常把大气折射率的非均匀性称为湍流“旋涡”,可以把他们想像成一些空气包,每个空气包鄞有一个特征的折射率。均匀湍流的功率谱密度Φ,(K)可以看成是尺度为L=2x/k,L=2x/和L,=2x/k的旋涡的相对丰度的一种量度。在各向同性湍流的情况下,Φ(K)仪是波数k的函数,k通过L=2x/k与旋涡大小L相联系。在 Kolmogorov关于湍流理论的终典工作的基础,普遍认为功率谱密度Φn(K)包括三个不同的区。对于很小的k=2n/L0(很大规模的尺寸)的区域叫输入区,在这个区域内谱的形状取决于特定的湍流是如何发生的,而且它通常是各向异性的。在这个区域被理论不能预言Φ(K)的数学形式。但当k大于某一临界波数λ时,Φ(K)的形状由制约着大湍流旋涡破碎为小旋涡的物理定律来决定。当k大于k0时,k0≈2x/,就进入了谱的惯性子区间。这里的Φn的形式可以由已确立的制约湍流的物理定律描述。由Kσ oImogoro湍流理论,Φ,为D(K)=0033C2k-1/32.5)当k达到了另一个临界值k的形式再次改变,这个区域叫耗散区,在这个区域里能量的耗散超过了动能。因此能量很小。所以,当k>k时,Φ很快下降。这里kn≈2π/l。 Tatarski川如下模型来概括k>k时Φn的快速下降:29C1994-2010ChinaAcademicJournalElcctronicPublishinghOusc.Allrightsrescrved.http://www.cnki.ncton(k)=0.033C, exp(k/km)(2.6)若选取kn=5.92/l,并且k>kn,上式是一个合理的近似。由式(25)和(2.6)所表示的谱在原点均偶不可积的极点,为了克服这种模型的缺点,常采用一种称为Ⅴ on karman谱的形式。这时谱近似地表示为0.033CΦ(k)≈(k2+k2)16 exp(- /km)Andrews提出了一个的近似谱8Φ(0.033 CR exp(-k2/k2)7/61+aQ2((k2+k2)16(28)k1k1其屮,a1=1.802,a2=0.254,k,-3.3/。注意,在a1=a2=0和作k=kn代换后Andrews模式简化为 Von karman谱;当k=l=0时,上式退化为(25)式。激光在大气中的传输方程假定大气的磁导率为常数,介电常量是随空间变化的。对于单色电磁波在地球大气中的传播,这时 Maxwell方程取以下形式l9V·H=0V×E=jboH(2.9)EOoEV·(EE)=0式(2.9)中,E是电场;H是磁场;a是角频率;而V矢量的分量为(O/ax,0/Cy,O/az)。把V×运算应用于式(29)的第二个方程,并将第二方程代入第三个方程,并考虑第四个方程,我们得到V·E+AHEE+V(E·Vlns)=0(2.10)这里代表以e为底的对数。波传播的局域速度即某点上的速度是(e)12,它也等于ch,式中,c是自由空间中的光速,而n是同一点上的局部折射率,因此u8=n/(2.11)由于和c是常数,有VIne=2vIn n(2.12)将式(2.11)和(2.12)代入式(210),得到C1994-2010ChinaAcademicJournalElcctronicPublishinghOusc.Allrightsrescrved.http://www.cnki.nct
- 2020-12-04下载
- 积分:1