URDF的關節定義:

<joint name="my_joint" type="floating">
    <origin xyz="0 0 1" rpy="0 0 3.1416"/>
    <parent link="link1"/>
    <child link="link2"/>

    <calibration rising="0.0"/>
    <dynamics damping="0.0" friction="0.0"/>
    <limit effort="30" velocity="1.0" lower="-2.2" upper="0.7" />
    <safety_controller k_velocity="10" k_position="15" soft_lower_limit="-2.0" soft_upper_limit="0.5" />
 </joint>

關節裏面首先定了父link跟子link, 以及關節的轉動軸.

接著是傳感器的定義:

攝像頭:

 <sensor name="my_camera_sensor" update_rate="20">
   <parent link="optical_frame_link_name"/>
   <origin xyz="0 0 0" rpy="0 0 0"/>
   <camera>
     <image width="640" height="480" hfov="1.5708" format="RGB8" near="0.01" far="50.0"/>
   </camera>
 </sensor>

激光傳感器:

 <sensor name="my_ray_sensor" update_rate="20">
   <parent link="optical_frame_link_name"/>
   <origin xyz="0 0 0" rpy="0 0 0"/>
   <ray>
     <horizontal samples="100" resolution="1" min_angle="-1.5708" max_angle="1.5708"/>
     <vertical samples="1" resolution="1" min_angle="0" max_angle="0"/>
   </ray>
 </sensor>

ROS之urdf 2