Working With Range of Motion (ROM) Files Tutorial

By Jimmy Almeida and Kevin Wang


This tutorial expands on the information covered in the transferring optical data to joints videos. The tutorial also covers Rigid Bodies and contact planes.

(This needs to be done for every range of motion file or ROM file.  Usually there are 2 ROM files per day.  This will allow you to create a file to check all cleaned raw data.)

1. Open Motion Builder (MB) and Import the *_ROM.c3d file.

2. You may have to rotate it so that it is facing positive Z.

3. Choose the proper animation in the Transport Controls Pane.  Change the Take001 to *_ROM

4. Double click on the Optical Pane and create Rigid Bodies (RB) under the Rigid Bodies tab. Follow the structure below.  RB are depicted by the red markers.

5. Check the RB’s for jitteriness in the optical data.  Click on one of the red markers.  Open the Optical Pane and click on the settings tab.  Check the “show rigid body quality” box.  A grayscale line appears along the bottom of the pane.   If something is black, it should be looked at and tweaked in MB or in VICON.  Do this for each red marker.

6. In the Asset Browser under Character, click and drag an Actor into the scene.  A gray figure appears.  This will drive your optical data.

7. Align the optical data as best as possible by going into the front view (Ctrl+F) and moving the data so that it is centered on the Actor.  When you are done, go back to the Perspective View (Ctrl+E)

8. Spacebar+Right Click (SBRC) the Hips.  Scale the actor to the proper proportion of the optical data.  The markers should fit pretty close to the way they did on the talent.  If you need to scale, use it sparingly.  Things don’t have to fit perfectly, but they should line up properly.  In other words, the data in the knee doesn’t need to touch the actor, but it should line up with it so that the creases are together.

9. If the marker data is further out that the actors proportions, you can non-uniformly scale a particular area, but this should be limited.