Gimbal URDF used in DJI M100 Gazebo Simulation.

gimbal.urdf.xacro

<?xml version="1.0"?>

<robot xmlns:xacro="http://www.ros.org/wiki/xacro">
    <xacro:macro name="dji_m100_gimbal">
        <joint name="virtual_gimbal_joint" type="fixed">
            <origin xyz="-0.1 0 -0.04" rpy="0 0 0"/>
            <parent link="base_link"/>
            <child link="virtual_gimbal_link"/>
        </joint>
        <gazebo reference="virtual_gimbal_joint">
            <preserveFixedJoint>true</preserveFixedJoint>
        </gazebo>
        <link name="virtual_gimbal_link">
            <inertial>
                <mass value="0.0001" />
                <origin xyz="0 0 0" rpy="0 0 0" />
                <inertia ixx="0.0001" ixy="0" ixz="0" iyy="0.0001" iyz="0" izz="0.0001" />
            </inertial>
            <visual>
                <geometry>
                <box size="0.0001 0.0001 0.0001" />
                </geometry>
            </visual>
            <collision>
                <origin xyz="0 0 0" rpy="0 0 0" />
                <geometry>
                <mesh filename="package://dji_m100_description/meshes/dji_m100/gimbal.stl"/>
                </geometry>
            </collision>
        </link>
        <joint name="gimbal_roll_joint" type="continuous">
            <parent link="virtual_gimbal_link" />
            <child link="gimbal_roll_link" />
            <axis xyz="1 0 0" />
            <dynamics damping="0.0" friction="0.0" />
        </joint>
        <link name="gimbal_roll_link">
            <inertial>
                <mass value="0.0001" />
                <origin xyz="0 0 0" rpy="0 0 0" />
                <inertia ixx="0.0001" ixy="0" ixz="0" iyy="0.0001" iyz="0" izz="0.0001" />
            </inertial>
            <visual>
                <geometry>
                <box size="0.0001 0.0001 0.0001" />
                </geometry>
            </visual>
        </link>
        
        <joint name="gimbal_pitch_joint" type="continuous">
            <parent link="gimbal_roll_link" />
            <child link="gimbal_pitch_link" />
            <axis xyz="0 1 0" />
            <dynamics damping="0.0" friction="0.0" />
        </joint>
        <link name="gimbal_pitch_link">
            <inertial>
                <mass value="0.0001" />
                <origin xyz="0 0 0" rpy="0 0 0" />
                <inertia ixx="0.0001" ixy="0" ixz="0" iyy="0.0001" iyz="0" izz="0.0001" />
            </inertial>
            <visual>
                <geometry>
                <box size="0.001 0.0001 0.0001" />
                </geometry>
            </visual>
        </link>
        <joint name="gimbal_yaw_joint" type="continuous">
            <parent link="gimbal_pitch_link" />
            <child link="gimbal_yaw_link" />
            <axis xyz="0 0 1" />
            <dynamics damping="0.0" friction="0.0" />
        </joint>
        <link name="gimbal_yaw_link">
            <inertial>
                <mass value="0.0001" />
                <origin xyz="0 0 0" rpy="0 0 ${-M_PI}" />
                <inertia ixx="0.0001" ixy="0" ixz="0" iyy="0.0001" iyz="0" izz="0.0001" />
            </inertial>
            <visual>
                <origin xyz="0 0 0" rpy="0 0 ${-M_PI}" />
                <geometry>
                <mesh filename="package://dji_m100_description/meshes/dji_m100/gimbal.dae"/>
                </geometry>
            </visual>
            <collision>
                <origin xyz="0 0 0" rpy="0 0 ${-M_PI}" />
                <geometry>
                <mesh filename="package://dji_m100_description/meshes/dji_m100/gimbal.stl"/>
                </geometry>
            </collision>
        </link>
        <joint name="camera_joint" type="continuous">
            <parent link="gimbal_yaw_link" />
            <child link="camera_link" />
            <axis xyz="0 0 1" />
            <dynamics damping="0.0" friction="0.0" />
        </joint>
        <link name="camera_link">
        </link>

        <joint name="camera_optical_joint" type="fixed">
            <origin xyz="0 0 0" rpy="${-M_PI/2} 0.0 ${-M_PI/2}" />
            <parent link="camera_link" />
            <child link="camera_optical_frame"/>
        </joint>
        <gazebo reference="camera_optical_joint">
            <preserveFixedJoint>true</preserveFixedJoint>
        </gazebo>
        <link name="camera_optical_frame">
        </link>
        
        <gazebo reference="gimbal_yaw_link">
            <sensor type="camera" name="camera_camera_sensor">
                <update_rate>10</update_rate>
                <camera>
                <!-- <pose>0.027 0 -0.027 0 1.57 0</pose> -->
                <!-- <pose>0.027 0 -0.027 0 1.57 0</pose> -->
                <pose>0.107 0 -0.127 0 0 0</pose>
                <horizontal_fov>${94 * M_PI/180.0}</horizontal_fov>
                <image>
                    <format>R8G8B8</format>
                    <width>640</width>
                    <height>480</height>
                </image>
                <clip>
                    <near>0.01</near>
                    <far>100</far>
                </clip>
                </camera>

                <plugin name="camera_controller" filename="libgazebo_ros_camera.so">
                <cameraName>camera</cameraName>
                <alwaysOn>true</alwaysOn>
                <updateRate>10</updateRate>
                
                <imageTopicName>dji_sdk/image_raw</imageTopicName>
                <cameraInfoTopicName>dji_sdk/camera_info</cameraInfoTopicName>
                <frameName>camera_optical_frame</frameName>
                </plugin>
            </sensor>
        </gazebo>
    </xacro:macro>
</robot>