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Binding a force plate to a rigid body

For portable force plates, frequent movement during actual use complicates the spatial position measurement process. The display position of the force plate in the software cannot accurately reflect its real spatial position, affecting the accuracy of the 3D view and the overall usability of the system. In this usage scenario, the function of binding the force plate to a rigid body can be utilized to automatically update the spatial position and posture of the force plate.

Using the Bertec force plate as an example, here is the user guide for the function of binding the force plate to a rigid body:

  1. First, align the position of the force plate with the global coordinate system. When using multiple force plates, they should be placed sequentially, and the initial position and directional parameters in space should be measured and recorded.
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  1. Check if the test parameters are correct： 1.Stick marker points on the four corners of the force plate and observe whether the four marker points in the 3D view align with the corners. This ensures that the initial position of the force plate is correct. If they are not aligned, please modify the position parameters of the force plate in the configuration until the initial position is correct.
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2.After setting the directional parameters in space, apply force to the force plate and observe the position of the force lever in the 3D view. If the position of the force is displayed incorrectly, please readjust the directional parameters. 3. In real-time mode, create a rigid body from the four marker points attached to the corners of the force plate. If it is inconvenient for the subsequent use of the force plate to attach the four marker points to the corners, you can also use a rigid body, such as an L-shaped rod. Place the L-shaped rod at one corner of the force plate to create the rigid body (it is recommended to use fixed points, as this will enhance the accuracy of updating the position and orientation of the force plate in the future).

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  1. Open the force plate configuration window, select the added force plate, choose the name of the rigid body created in Step Four from the binding rigid body list, and click the update position button. The rigid body will be successfully bound to the force plate.
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  1. Click the "Clear" option in the binding rigid body list to remove the currently bound rigid body from the force plate.
  2. After moving the position of the force plate, click the "Update Position" button to complete the update of the position and orientation of the force plate, without the need to manually adjust the position and orientation parameters.
  3. In scenarios with multiple force plates, this function requires binding each force plate separately in the force plate configuration window. After completing the binding, click the "Update Position" button to finish updating the position and orientation of the force plates.
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  1. If a rigid body is created using fixed points for binding, do not move the position of the marker points on the force plate. If the position of the marker points changes, please recreate the rigid body and bind it to the force plate before updating the position and orientation.
  2. If a rigid body is created using a non-fixed method for binding, bind the force plate and click the "Update Position" button to complete the process. Use markers to record the current position of the rigid body. Before the next position update for the force plate, ensure that the rigid body is placed in the correct position. If there is an error between the position of the rigid body and the initial binding position of the force plate, it may lead to decreased accuracy after the position and orientation update. In such cases, it is recommended to recreate the rigid body and bind it again before updating the position.