The segment to center of forceplatfrom distance is the maximum distance to look when assigning segments to forceplatforms used in the motion files. The value indicates the distance from the COP of the force platform the foot's center of mass.

Visual3D's default value is 0.2 m, but this can be tweaked depending on the scale of the data, the task being performed by the subject, or depending on how segments are defined in order to properly assign a segment to a force value. If 0.2 m is working for your data, then there is no reason to change it from this default value. This is created automatically by Visual3D, and can be modified to change the value for a specific model.

The COP Distance is a threshold distance that must be satisfied in order to identify a force assignment. If the distance is too small, and the COP error is a little too high, a recognizable assignment might not be made. The default value of 0.2m has proven to be an acceptable value, so users should refrain from modifying this value unless they have a very good reason.

To change the Visual3D's default value:

1. Select Modify FP Center of Pressure distance to segment… from the Force drop down menu
2. Change the value in the Set the distance of FP Center of Force Pressure to nearest segment dialog box

To change the value for an individual subject:

1. Go to the Models tab
   1. Click the Subject Data/Metrics button
   2. Change the Segment_to_COFP_Distance value

Once the value has been changed, make sure to Build Model and then Recalc to update the force assignments.