How Do I Convert a SolidWorks File to URDF?

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In this tutorial, we will explore how to convert a SolidWorks file to URDF. URDF stands for Unified Robot Description Format, which is an XML file format used to describe robots in the Robot Operating System (ROS) ecosystem. Converting a SolidWorks file to URDF is an essential step in integrating your robot model into ROS for simulation or control.

Step 1: Exporting the SolidWorks Model
To begin, you need to export your SolidWorks model as a COLLADA (.dae) file. COLLADA is a widely supported 3D interchange format that can be used to transfer models between different software applications.

Here’s how you can do it:

  1. Open your SolidWorks model.
  2. Select ‘File’ > ‘Save As’ and choose the COLLADA format (.dae).
  3. Specify the name and location for the exported file, and click ‘Save’.
  4. In the Export Options dialog, select the desired options for exporting geometry, appearances, and units.
  5. Click ‘OK’ to export your model as a COLLADA file.

Step 2: Using ROS Packages
Next, you need to have ROS installed on your system along with some additional packages that facilitate the conversion process. Make sure you have the following packages installed:

  • xacro: This package provides tools for processing macro files, which are commonly used in URDF creation.
  • collada_urdf: This package enables conversion from COLLADA files to URDF files.

If you don’t have these packages installed, open your terminal and run the following commands:

$ sudo apt-get install ros-melodic-xacro
$ sudo apt-get install ros-melodic-collada-urdf

Step 3: Converting the COLLADA File to URDF
Once you have the required packages installed, you can proceed with the conversion process. Open your terminal and follow these steps:

  1. Navigate to the directory where your COLLADA file is located.
  2. Run the following command to convert the COLLADA file to URDF:
$ rosrun collada_urdf collada_to_urdf my_model.dae my_model.urdf

Replace ‘my_model.dae’ with the actual name of your COLLADA file and ‘my_model.urdf’ with the desired name for your URDF file.

Step 4: Inspecting and Modifying the URDF File
After successful conversion, you can open the generated URDF file using a text editor. The URDF file contains all the necessary information about your robot model, such as links, joints, visual and collision properties.

Here are some key elements you might want to inspect or modify:

  • Links: Each link represents a physical component of your robot. Inspect the visual and collision properties defined for each link.
  • Joints: Joints define how different links are connected and allow movement between them. Make sure they are correctly specified.
  • Visuals and Collisions: Inspect and modify visual and collision properties such as geometry, material, origin, etc., as per your requirements.

Step 5: Using the URDF Model in ROS
Now that you have successfully converted your SolidWorks model to URDF, you can use it within ROS for various purposes like simulation or control. To use the URDF model, you need to create a ROS package and include the URDF file in it.

Here’s a brief overview of how to use your URDF model in ROS:

  1. Create a new ROS package using the following command:
$ catkin_create_pkg my_robot_description
  • Create a ‘urdf’ directory within your package and move the generated URDF file into it.
  • Create a launch file to load and visualize your robot model using RViz or any other visualization tool.
  • Build and source your workspace using the following commands:
    • $ catkin_make
$ source devel/setup.bash

    Congratulations! You have successfully converted your SolidWorks file to URDF and can now use it within ROS for further development, simulation, or control.

    I hope this tutorial was helpful in guiding you through the process of converting a SolidWorks file to URDF. Remember, proper conversion and inspection of your model are crucial for accurate representation in ROS. Happy robot modeling!