Motion Capture Demo

++Overview

• Motion Analysis hardware
• optical motion capture
• 10 Hawk cameras
• EVarts 5.04 software

++Uses of Character Animation, pipeline overview

• file formats
• Autodesk MotionBuilder 7.5
• marker sets
• TGEA

++Motion Capture Production (EVarts 5.04)

• Load a previous marker set (project (.prj) file)
  • Marker set will be visible in post-process tab
  • The number of markers will directly reflect the number of tracks in your track(.trc) file
  • this will translate to points on the skeleton rig
  • depending what your final destination for your Motion capture is, this may be dictate from the model being animated (if it is already created or not)
  • in either case, the data can be massaged later in the pipeline (better to have more)
• Calibration L-seed - switch to calibration tab
  • Turn on the cameras, put the L-device on the floor, connect to cameras
  • "Run" the cameras for a couple seconds
• Mask out
  • switch to 2d mode, for each camera mask out any extraneous areas using middle mouse button (wheel)
  • basically, you should only see the four L dots from each camera angle. mask out anything else by click and dragging rectangles
  • for each camera, use tools ==> camera settings, to adjust the threshold to approximately 300
  • "run" the cameras for a couple seconds
  • review masking for each camera, making sure there are no extraneous red/black marks
  • for each camera, click on Preview calibrations, ok to overwrite and "Collect and calibrate" button
• wand calibration
  • (remove the l-seed)
  • run the cameras by hitting the run button
  • click on the ok to overwrite under the "calibration with wand" section
  • click "Collect and Calibrate"
  • swinging the 500mm wand around the capture volume, specifically around the perimeter. Do this for at least two minutes; then hit run/pause to stop. It will take the machine several second to calculate the data. You will get a box that shows the # of frames captures, etc. They should all be fairly similar in the 5000 range but variation will occur. Just note that they all all similar in scale this shows that the cameras are working properly. (4000-10000), click OK and then you get a "wand processing status table generated. Click accept if you are ready to accept. Save as system calibration
• floor calibration
  • place 9 morkers, eight in corners, sides, 1 in the middle of the capture volume
  • hit OK to Overwrite and then Collect and calibrate
• ROM and Data output setup
  • in the motion capture tab, (output tab): activate Raw Video output (.vc*, tracked ASCII (.trc), and traked binary (.trb)
  • suit UP!
  • make sure the cameras are running,
  • hit RECORD
  • walk into the capture volume and do a T-pose for at least several seconds

capture

• • this records a .trb file that is then manually brought into post process (or hit "Load Last capture")
• EVarts 5.04 Post production

++Autodesk MotionBuilder 7.5

• inputting TRC data
• cleaning up TRC data
• animation
• Output formats