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前置安装：VMware虚拟机，ubuntu版本：20.04，ROS版本：noetic

前置软件：VScode、Terminator等

编程语言：Python

一、创建机器人模型

        ROS官方教程中的通过直接编写urdf文件的方式过于繁琐，且其推荐的xacro语言也同样无法解决需要人为计算的弊病。

1、个人推荐较为直观的从三维建模软件（此处为SOLIDWORKS）建模软件直接导出urdf文件。相关的教程可在CSDN找到，此处不再赘述。

Solidworks模型导出urdf – 知乎

        需要作如下几点说明：        

        1）导出的urdf文件可通过宿主机与虚拟机建立共享文件夹传输，简单快捷

https://jingyan.baidu.com/article/f79b7cb38e5391d144023ead.html

        2）sw建模时尽量将命名作规范

        3）注意各坐标系的相对位置关系，尽可能按一定规律如将Z轴作为旋转轴等，这里以ROS官方教程中的机器人为例：

2、得到机器人模型文件后在ubuntu VScode中打开（按教程修改package.xml等）

其中urdf文件夹下的为导出的urdf文件

meshes文件夹下的为stl格式的三维模型，可以在扩展中扩展stl viewer之类的插件查看三维模型

launch文件夹中包含了两个launch文件，分别是在rviz中显示和在gazebo中显示

1）display.launch

<launch>
  <arg
    name="model" />
  <!-- 加载机器人模型 -->
  <param
    name="robot_description"
    textfile="$(find slam_car_urdf)/urdf/slam_car_urdf.urdf" />
  <!-- 启动机器人状态发布节点（缺少会在rviz中报错：no transform from  ....） -->
  <node
    name="joint_state_publisher_gui"
    pkg="joint_state_publisher_gui"
    type="joint_state_publisher_gui" />
  <node
    name="robot_state_publisher"
    pkg="robot_state_publisher"
    type="robot_state_publisher" />
  <!-- 启动rviz -->
  <node
    name="rviz"
    pkg="rviz"
    type="rviz"
    args="-d $(find slam_car_urdf)/urdf.rviz" />
</launch>

2）gazebo.launch

<launch>
  <!-- 启动gazebo创建新空间 -->
  <include
    file="$(find gazebo_ros)/launch/empty_world.launch" />
  <!-- 某种坐标转换发布节点 -->
  <node
    name="tf_footprint_base"
    pkg="tf"
    type="static_transform_publisher"
    args="0 0 0 0 0 0 base_link base_footprint 40" />
  <!-- 加载urdf机器人模型信息 -->
  <node
    name="spawn_model"
    pkg="gazebo_ros"
    type="spawn_model"
    args="-file $(find slam_car_urdf)/urdf/slam_car_urdf.urdf -urdf -model slam_car_urdf"
    output="screen" />
  <!-- 不知道干嘛用的校准节点 -->
  <node
    name="fake_joint_calibration"
    pkg="rostopic"
    type="rostopic"
    args="pub /calibrated std_msgs/Bool true" />
</launch>

3)

<?xml version="1.0" encoding="utf-8"?>
<!-- This URDF was automatically created by SolidWorks to URDF Exporter! Originally created by Stephen Brawner (brawner@gmail.com) 
     Commit Version: 1.6.0-4-g7f85cfe  Build Version: 1.6.7995.38578
     For more information, please see http://wiki.ros.org/sw_urdf_exporter -->
<robot
  name="slam_car_urdf">
  <link
    name="base_link">
    <inertial>
      <origin
        xyz="-1.79451050096713E-17 0 0.0225"
        rpy="0 0 0" />
      <mass
        value="2.51327412287183" />
      <inertia
        ixx="0.00762359817271123"
        ixy="1.07186196898297E-50"
        ixz="-2.72707632382106E-18"
        iyy="0.00762359817271123"
        iyz="-1.94272883206886E-35"
        izz="0.0125663706143592" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/base_link.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/base_link.STL" />
      </geometry>
    </collision>
  </link>
  <link
    name="right">
    <inertial>
      <origin
        xyz="-3.60878140608269E-19 6.93889390390723E-18 -0.00749999999999999"
        rpy="0 0 0" />
      <mass
        value="0.0577267650097125" />
      <inertia
        ixx="1.87611986281566E-05"
        ixy="-4.27201574096171E-38"
        ixz="-1.80534032376123E-23"
        iyy="1.87611986281566E-05"
        iyz="6.67041240997494E-22"
        izz="3.53576435684489E-05" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/right.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/right.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="r"
    type="continuous">
    <origin
      xyz="0 -0.115 0"
      rpy="1.5707963267949 0 0" />
    <parent
      link="base_link" />
    <child
      link="right" />
    <axis
      xyz="0 0 1" />
  </joint>
  <link
    name="left">
    <inertial>
      <origin
        xyz="-2.67972330793522E-19 3.46944695195361E-18 0.00750000000000001"
        rpy="0 0 0" />
      <mass
        value="0.0577267650097125" />
      <inertia
        ixx="1.87611986281566E-05"
        ixy="-1.74700545371199E-21"
        ixz="8.10839387363186E-24"
        iyy="1.87611986281565E-05"
        iyz="6.36832889208227E-22"
        izz="3.53576435684489E-05" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/left.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/left.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="left_driven"
    type="continuous">
    <origin
      xyz="0 0.115 0"
      rpy="1.5708 0 0" />
    <parent
      link="base_link" />
    <child
      link="left" />
    <axis
      xyz="0 0 1" />
  </joint>
  <link
    name="front">
    <inertial>
      <origin
        xyz="0 -2.3404423700906E-19 0"
        rpy="0 0 0" />
      <mass
        value="0.00176714586764426" />
      <inertia
        ixx="3.97607820219958E-08"
        ixy="2.86886809144189E-24"
        ixz="-3.22897170824252E-24"
        iyy="3.97607820219958E-08"
        iyz="-4.24929064425396E-24"
        izz="3.97607820219958E-08" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/front.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/front.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="f_driven"
    type="continuous">
    <origin
      xyz="0.07 0 -0.025"
      rpy="0 0 0" />
    <parent
      link="base_link" />
    <child
      link="front" />
    <axis
      xyz="1 0 0" />
  </joint>
  <link
    name="back">
    <inertial>
      <origin
        xyz="0 1.1702211850453E-19 8.67361737988404E-19"
        rpy="0 0 0" />
      <mass
        value="0.00176714586764426" />
      <inertia
        ixx="3.97607820219958E-08"
        ixy="2.04657953337569E-24"
        ixz="-4.90432414504321E-24"
        iyy="3.97607820219958E-08"
        iyz="-3.46956680478304E-24"
        izz="3.97607820219958E-08" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/back.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/back.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="back_driven"
    type="continuous">
    <origin
      xyz="-0.07 0 -0.025"
      rpy="0 0 0" />
    <parent
      link="base_link" />
    <child
      link="back" />
    <axis
      xyz="1 0 0" />
  </joint>
  <link
    name="camera">
    <inertial>
      <origin
        xyz="0 -4.12335585688332E-18 0.0125"
        rpy="0 0 0" />
      <mass
        value="0.00625" />
      <inertia
        ixx="6.51041666666667E-07"
        ixy="-5.95728924546422E-24"
        ixz="1.64948095499974E-22"
        iyy="3.77604166666667E-07"
        iyz="4.99809992886639E-23"
        izz="3.77604166666667E-07" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/camera.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/camera.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="camera_fixed"
    type="fixed">
    <origin
      xyz="0.08 0 0.0625"
      rpy="0 0 0" />
    <parent
      link="base_link" />
    <child
      link="camera" />
    <axis
      xyz="0 0 0" />
  </joint>
  <link
    name="laser_support">
    <inertial>
      <origin
        xyz="-4.1413007865299E-17 -5.2907515930031E-19 0.075"
        rpy="0 0 0" />
      <mass
        value="0.0471238898038469" />
      <inertia
        ixx="8.9535390627309E-05"
        ixy="4.96308367531817E-23"
        ixz="4.80993864318015E-20"
        iyy="8.9535390627309E-05"
        iyz="2.8535407990337E-37"
        izz="2.35619449019235E-06" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/laser_support.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/laser_support.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="laser_sup_fixed"
    type="continuous">
    <origin
      xyz="0 0 0.0625"
      rpy="0 0 0" />
    <parent
      link="base_link" />
    <child
      link="laser_support" />
    <axis
      xyz="0 0 1" />
  </joint>
  <link
    name="laser">
    <inertial>
      <origin
        xyz="-1.34362177014971E-17 -2.03864780368065E-18 0.025"
        rpy="0 0 0" />
      <mass
        value="0.141371669411541" />
      <inertia
        ixx="6.12610567450009E-05"
        ixy="2.76303274868706E-36"
        ixz="-2.38538838926736E-21"
        iyy="6.12610567450009E-05"
        iyz="-5.37308287535703E-22"
        izz="6.36172512351933E-05" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/laser.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="1 1 1 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://slam_car_urdf/meshes/laser.STL" />
      </geometry>
    </collision>
  </link>
  <joint
    name="laser_fixed"
    type="continuous">
    <origin
      xyz="0 0 0.15"
      rpy="0 0 0" />
    <parent
      link="laser_support" />
    <child
      link="laser" />
    <axis
      xyz="0 0 1" />
  </joint>
</robot>

可以看到插件帮我们导出了模型的必要信息，节点的信息如质量mass、提供碰撞检测的依据collision 、刚体部分的惯性矩阵intertial等，关节信息如装配的相对位置关系origin、导出时配置的坐标系axis、关节类型type等等。

二、在机器人模型的基础上配置雷达并在rviz和gazebo中仿真

1、配置雷达文件

  官方文档：

<robot name="my_sensors" xmlns:xacro="http://wiki.ros.org/xacro">
<!-- 此处reference与laser link名相同 -->
  <gazebo reference="laser">
<!-- 以下为雷达参数配置-->
    <sensor type="ray" name="rplidar">
      <pose>0 0 0 0 0 0</pose>
      <visualize>true</visualize>
      <update_rate>5.5</update_rate>
      <ray>
        <scan>
          <horizontal>
            <samples>360</samples>
            <resolution>1</resolution>
            <min_angle>-3</min_angle>
            <max_angle>3</max_angle>
          </horizontal>
        </scan>
        <range>
          <min>0.10</min>
          <max>30.0</max>
          <resolution>0.01</resolution>
        </range>
        <noise>
          <type>gaussian</type>
          <mean>0.0</mean>
          <stddev>0.01</stddev>
        </noise>
      </ray>
      <plugin name="gazebo_rplidar" filename="libgazebo_ros_laser.so">
        <topicName>/scan</topicName>
        <frameName>laser</frameName>
      </plugin>
    </sensor>
  </gazebo>

</robot>

2、在gazebo中显示机器人模型并在rviz读取雷达数据

1）新建.xacro文件，将urdf文件内容复制粘贴进，在开头的robot标签中加入xmlns语句，在末尾</robot>标签前添加即可：

<xacro:include filename="camera_config.xacro">

 2)编写launch文件

<launch>
<!-- 加载机器人模型参数到参数服务器 -->
<param name="robot_description" command="$(find xacro)/xacro $(find slam_car_urdf)/urdf/slam_car.xacro"/>

<!-- 启动gazebo -->
<include file="$(find gazebo_ros)/launch/empty_world.launch"/>
<!-- 在gazebo中显示机器人模型 -->
<node pkg="gazebo_ros" type="spawn_model" name="model" args="-urdf -model mycar -param robot_description"/>
<!-- 在rviz中导入机器人参数 -->
<node name="joint_state_publisher_gui" pkg="joint_state_publisher_gui" type="joint_state_pulisher_gui"/>
<node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher"/>
<node="rviz" pkg="rviz" type="rviz" args="-d $(find slam_car_urdf)/urdf.rviz"/>
</launch>

3)命令行roslaunch运行此launch文件（之前没编译过记得catkin_make）

在gazebo中添加障碍物并配置rviz