title: How to simulate fixed plane using SimScape Multibody Contact Forces Library?
body: <p>I am trying to simulate the contact forces between a fixed plane and a sphere in MATLAB Simulink using the Multibody Contact Forces Library <a href="https://www.mathworks.com/matlabcentral/fileexchange/47417-simscape-multibody-contact-forces-library" rel="nofollow noreferrer">https://www.mathworks.com/matlabcentral/fileexchange/47417-simscape-multibody-contact-forces-library</a> as shown in this MATLAB webinar <a href="https://www.youtube.com/watch?v=VZIG0HlBHC4" rel="nofollow noreferrer">https://www.youtube.com/watch?v=VZIG0HlBHC4</a> at 9:58. However, when I recreate the model and run the simulation myself, I get the following error.</p>
  
  <pre><code>External Force and Torque External_Force_and_Torque_PlaB has its follower port rigidly connected to the world frame; it has no effect. You can configure this diagnostic in the Simscape Multibody Configuration Parameters dialog.
  </code></pre>
  
  <p>I've tried adding another constraint/joint between the World Frame and the planar solid to resolve the issue, but I keep getting the same error? How can I fix this error?</p>