We add the laser scanner on the top of Gazebo to perform high-end operations, such as autonomous navigation or map creation using this robot. Here, we should add the following extra code section to diff_wheeled_robot.xacro to add the laser scanner to the robot:
<link name="hokuyo_link"> <visual> <origin xyz="0 0 0" rpy="0 0 0" /> <geometry> <box size="${hokuyo_size} ${hokuyo_size} ${hokuyo_size}"/> </geometry> <material name="Blue" /> </visual> </link> <joint name="hokuyo_joint" type="fixed"> <origin xyz="${base_radius - hokuyo_size/2} 0 ${base_height+hokuyo_size/4}" rpy="0 0 0" /> <parent link="base_link"/> <child link="hokuyo_link" /> </joint> <gazebo reference="hokuyo_link"> <material>Gazebo/Blue</material> ...