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(As of Motive 1.9.0 we only support systems with AMTI Gen 5 amplifiers)
To install plug each force plate into a separate Gen 5 amplifier, plug a USB 2.0 type B to A cable from each amplifier to your computer, then set up the camera system as normal (see Hardware Setup page).
For better sync using an Ethernet based prime series camera system, connect an eSync2 to your camera system, then connect the eSync2 and your Gen 5 amplifer(s). To connect the two use one of the “50 Ohm BNC Male to 75 Ohm RCA Jack Adapters” included with the eSync as well as an RCA male to male cable in one of the four output ports of the eSync to the sync port of the Gen 5 amplifier.
For better sync using a USB 2.0 based flex series camera system you can do one of two things. Connect a “50 Ohm BNC Male to 75 Ohm RCA Jack Adapters” into the output port on your OptiHub(s) and connect each OptiHub to a corresponding force plate using a male to male RCA cable. (Note: you need an OptiHub for each force plate this way.) Alternately you may use a BNC splitter to use one OptiHub as a master sync for your force plates. (Note: you may need to use an active BNC splitter because you lose some power each time you passively split the signal.) Without the presence of an eSync your motion capture and force plate data may be as much as 1-2 frames off.
Installation Note: If you install AMTI, then Motive everything should work fine. However, if you install Motive, the AMTI you may run into Visual Studio Redistributed 2010 issues.
1. Start Motive. If you set up the hardware and software correctly, then when you open motive you will see force plates with the numbers 1, 2, etc.. depending on how many force plates you have connected. If you did not set up the hardware and software correctly Motive will notify you if it detects a force plate, and an incorrect or nonexistent calibration file.
2. Calibrate cameras. Calibrate the volume as normal to get the orientation of cameras (see the Quick Start Guide or Calibration page for more information). The position of the force plate is relative to the center of the volume. So if you re-calibrate or reset the ground plane you will need to also realign the position of your force plates for best results.
3. Setup CS-400. Pull the force plate alignment tabs out and put the force plate levelings jigs on the bottom of your CS-400 calibration square. The leveling jigs align force plate to the surface of your force plate. The alignment tabs allow you to put the CS-400 flush against the sides of your force plate giving the most accurate alignment.
4. Place CS-400 on force plate. Place the Calibration wand with the corner of the force plate to the right of where the cable input is located. The direction matters, because it give you the proper orientation and some force plates are rectangular.
5. Set force plate position in Motive. Select the CS-400 markers in Motive then right click the force plate you want to assign to that position, and click Set position. To figure out which force plate the calibration square is on you can step on the force plate. A force vector will appear on the force plate you stepped on.
6. Zero force plates. After you have set all of your force plate’s with steps 4 and 5, remove the CS-400 from your force plates. Right click one of your force plates and click "Zero (all)". This will set the current force on the plate data to 0. This helps account for small constant amount that the force plate will be off by. Remember that it zeros all of the force plates at once. So make sure there are no objects on the force plates.
To view live force plate data open the project pane (or cameras pane) and timeline pane, then open the editor in the timeline pane. Select your force plate in the project pane (or cameras pane). Then select one of Fx, Fy, Fz, Mx, My, or Mz to view the live force plate data. This is a good way to confirm that your force plates are working.
1) Open the cameras Pane and the Synchronization Pane.
2) If you are using the eSync and a prime (ethernet system): In the synchronization pane select “Custom Synchronization” set sync input > Source = Internal clock. Set sync input > Clock Freq = 2000. Set Sync input > Input divider = 20. Set Sync output 1-4 > Type =Record Start/Stop Pulse. Then click apply. Then in the Cameras Pane select the force plates group. In Properties at the bottom select sync source = Free Run. It should look something like the following (change this to 1000 and 10):
Supported frame rates: 2000, 1800, 1500, 1200, 1000, 900, 800, 600, 500, 450, 400, 360, 300…etc These values can be found in the AMTI System Configuration Program.
If you are using a Flex (USB 2.0 system): In the synchronization pane select “Custom Synchronization” set External Sync Output > Type = Recording Level. It should look something like the following:
Note: the sync for the OptiHub may not be as true of a sync as the eSync.
The OptiHub only has one output BNC sync port. So you can only reliably do one force plate, but it may be possible to use a BNC splitter to increase this number. (It depend of the sensitivity of the force plate's receiver.)
If you are not using the eSync, but are using a prime system: Ignore the Synchronization pane. Just make sure that in the cameras pane that the force plate FPS is a multiple of the tracking FPS, ex 100fps and 1000fps. The issue with this method is that because there is no master synchronization device there might be drift in the data and the data will not trigger at the same time. This can be an issue for longer takes and if you want your system to be timed perfectly. Motive should alert you if your cameras and force plates do not have rates that work.
This is what it will look like if you don’t have the force plate sample rate as an integer multiple of the frame rate,
Record some force plate data!!!