Creating URDF is a time-consuming task; in this section, we will learn how to create a URDF package for a robot and insert 3D CAD models as a robot link in URDF. The first step is to create a robot description package; in this case, chapter_9_codes/chefbot_code/chefbot_description is our robot model ROS package. This package contains all the URDF files and 3D mesh files required for a robot. The chefbot_description/meshes folder has some 3D models that we designed earlier. These 3D models can be inserted into the URDF file. You can check the existing URDF file from chefbot_description/urdf. Here is a snippet that inserts a 3D model into URDF, which can act as a robot link. The code snippet can be found in urdf/chefbot_base.urdf.xacro.

       <joint name="base_joint" type="fixed"> 
          <origin xyz="0 0 0.0102" rpy="0 0 0" /> 
          <parent link="base_footprint"/> 
          <child link="base_link" /> 
       </joint> 
        <link name="base_link"> 
          <visual> 
            <geometry> 
 
              <!-- new mesh --> 
              <mesh 
     filename="package://chefbot_description/meshes/base_plate.dae" /> 
            </geometry> 

Here, you can see we are inserting the base_plate.dae mesh into the URDF file.