ros之launch文件

<launch>
  <arg name="model" default="model_name" doc="this is a model name"/>
  <arg name="param_path" default="$(find package_name)/data/" doc="this is a param path" />
  <group ns="group_name">
  <node pkg="package_name1" name="node_name1" type="node_type1" output="screen" >
    <param name="model" value="$(arg model)"/>
    <param name="param_path" value="$(arg param_path)/xx.xml" />
    <remap from="old_topic" to="new_topic"/>
  </node> 
  </group>

  <node pkg="package_name2" name="node_name2" type="node_type2" output="screen" >
    <param name="string" type="str" value="ABC" />
    <param name="int" type="int" value="6" />
    <rosparam param="min_in">[1, 1, 1]</rosparam>
    <rosparam param="paras">
      "a": 1
      "b": 2
    </rosparam>
  </node>

  <node pkg="rviz" name="rviz" type="rviz"  args="-d $(find package_name)/rviz/package_name.rviz">
  </node>
</launch>

• 對node設置組名

<group ns="group_name">
</group>

• 對topic重映射

<remap from="old_topic" to="new_topic"/>

• 設置參數

<param name="string_name" type="str" value="ABC" />
<param name="int_name" type="int" value="6" />
<param name="param_path" value="$(arg param_path)/xx.xml" />

type="str|int|double|bool|yaml"(optional)
注意：不支持float類型
注意：是str， 不是string

ros::NodeHandle priv_nh("~");
std::string string_name;
priv_nh.param<std::string>("string_name", string_name, "string_defalut");
priv_nh.param<int>("int_name", int, "0");

• 使用rosparam

<rosparam param="range">[1, 1, 1]</rosparam>

   <rosparam param="paras">
      "a": 1
      "b": 2
    </rosparam>

使用rosparam向node傳輸參數

std::vector<double> v_range(3, 0);
priv_nh.getParam("range", v_range);

std::map<std::string, double> m_paras;
priv_nh.getParam("paras", m_paras);

• 在launch文件中啟動其他launch文件

<launch>
  <include file="$(find packagexx)/launch/111.launch" />
</launch>

• 在launch文件中錄制rosbag包

<launch>
  <node name="record" pkg="rosbag" type="record" output="screen" args="-o  $(find record_bag)/../../bag /topic_1 /topic_2 /topic_3"/>
</launch>

參考

How to create a launch file? - ROS Answers: Open Source Q&A Forum
roslaunch/XML - ROS Wiki