If the controller configuration is ready, we can build a launch file that starts all the controllers along with the Gazebo simulation. Navigate to the seven_dof_arm_gazebo/launch directory and open the seven_dof_arm_gazebo_control.launch file:
<launch> <!-- Launch Gazebo --> <include file="$(find seven_dof_arm_gazebo)/launch/seven_dof_arm_world.launch" /> <!-- Load joint controller configurations from YAML file to parameter server --> <rosparam file="$(find seven_dof_arm_gazebo)/config/seven_dof_arm_gazebo_control.yaml" command="load"/> <!-- load the controllers --> <node name="controller_spawner" pkg="controller_manager" type="spawner" respawn="false" output="screen" ns="/seven_dof_arm" args="joint_state_controller ...