ROS使用gmapping以及hector进行slam建图

1>启动已有的机器人仿真环境。

roslaunch mbot_gazebo view_mbot_with_laser_gazebo_suyunzzz_world.launch

该launch文件如下

<launch>

    <!-- 设置launch文件的参数 -->
    <arg name="world_name" value="$(find mbot_gazebo)/worlds/suyunzzz_world.world"/>
    <arg name="paused" default="false"/>
    <arg name="use_sim_time" default="true"/>
    <arg name="gui" default="true"/>
    <arg name="headless" default="false"/>
    <arg name="debug" default="false"/>

    <!-- 运行gazebo仿真环境 -->
    <include file="$(find gazebo_ros)/launch/empty_world.launch">
        <arg name="world_name" value="$(arg world_name)" />
        <arg name="debug" value="$(arg debug)" />
        <arg name="gui" value="$(arg gui)" />
        <arg name="paused" value="$(arg paused)"/>
        <arg name="use_sim_time" value="$(arg use_sim_time)"/>
        <arg name="headless" value="$(arg headless)"/>
    </include>

    <!-- 加载机器人模型描述参数 -->
    <param name="robot_description" command="$(find xacro)/xacro --inorder '$(find mbot_description2)/urdf/xacro/gazebo/mbot_with_laser_gazebo.xacro'" /> 

    <!-- 运行joint_state_publisher节点，发布机器人的关节状态  -->
    <node name="joint_state_publisher" pkg="joint_state_publisher" type="joint_state_publisher" ></node> 

    <!-- 运行robot_state_publisher节点，发布tf  -->
    <node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher"  output="screen" >
        <param name="publish_frequency" type="double" value="50.0" />
    </node>

    <!-- 在gazebo中加载机器人模型-->
    <node name="urdf_spawner" pkg="gazebo_ros" type="spawn_model" respawn="false" output="screen"
          args="-urdf -model mrobot -param robot_description"/> 

</launch>

相对于机器人建模的那个文件更换了一个地图，该地图是自己绘制保存下来的。

2>启动建图节点(gmapping、hector)以及rviz

roslaunch wheel_chair_navigation gmapping_demo.launch
(roslaunch wheel_chair_navigation hector_demo.launch)

以gmapping为例，launch文件如下所示

<launch>

    <include file="$(find wheel_chair_navigation)/launch/gmapping.launch"/>

    <!-- 启动rviz -->
    <node pkg="rviz" type="rviz" name="rviz" args="-d $(find wheel_chair_navigation)/rviz/gmapping.rviz"/>

</launch>

其中，gmappiing.launch如下：

<launch>
    <arg name="scan_topic" default="scan" />

    <node pkg="gmapping" type="slam_gmapping" name="slam_gmapping" output="screen" clear_params="true">
        <param name="odom_frame" value="odom"/>
        <param name="map_update_interval" value="5.0"