How to use COP data

I want to change reaction points to COP by attached file.

Therefore ,I study GaitVaughan model.
But, I don’t understand Environment.any’s
“time.any”
“CenterOfPressurePlateOffset1.any”
“CenterOfPressurePlate1.any”
I want to know these file’s file.

If I change attached file’s Environment.any ,
This file’s reaction points become COP ?

Attached file’s text data is force data, c3d data is motion data.

Hi,

Let’s see the code in the ‘Environment.any’ file:

AnyKinLinear Lin1={
  AnyRefFrame &ref1=.GlobalRef;
  AnyRefFrame &ref2=.CenterOfPressure1;
};

AnyKinRotational Rot1={
  AnyRefFrame &ref1=.GlobalRef;
  AnyRefFrame &ref2=.CenterOfPressure1;
  Type=RotVector;
};

//The center of pressure has been moved sligthly sideways to obtain realistic
//abduction/adduction moment of the ankle
AnyKinEqInterPolDriver LinDrv1={
  AnyKinLinear &ref1= .Lin1;
  Type=PiecewiseLinear;
#include "time.any"
#include "CenterOfPressurePlateOffset1.any"
#include "CenterOfPressurePlate1.any"
Data =0.35*CenterOfPressurePlateOffset1'+CenterOfPressurePlate1';
  Reaction.Type={Off,Off,Off};
};

AnyKinEqSimpleDriver RotDrv1={
  AnyKinRotational &ref1= .Rot1;
  DriverPos={0,0,0};
  DriverVel={0,0,0};
  Reaction.Type={Off,Off,Off};
};

I think you have to see the definition of AnyKinEqInterPolDriver class in the reference manual. ‘Time.any’ file is required to define the time ‘T’ vector of this class. And using ‘CenterOfPressurePlateOffset1.any’ and ‘CenterOfPressurePlate1.any’ file, you can define ‘Data’ matrix which describes the value of AnyKinLinear object inside.

As you pointed out, the ‘CenterOfPressure1’ AnySeg will be as same as the COP. So all the forces will be acting on the segment.

Best regards,
Moonki

Thank you message, mkjung9980.

In sum,
Do I need to make
“time.any”
“CenterOfPressurePlateOffset1.any”
“CenterOfPressurePlate1.any” ?

And,
what’s the difference between “CenterOfPressurePlateOffset1.any”
and “CenterOfPressurePlate1.any” ?

I beg your kindness.

Hi,

It depends on what kinds of data your force plate system could generate.

If you see the ‘CenterOfPressurePlateOffset1.any’ file, then you can see that all rows are same. So we can guess that this ‘CenterOfPressurePlateOffset1.any’ file may contain the global location of the force plate.

But if you see the ‘CenterOfPressurePlate1.any’ file, the rows are different according to time. So we can guess that this file may contain the COP values with respect to the force plate coordinate system.

Of course I’m not sure. So you have to check which kinds of data you can get from your force plate system.

Best regards,
Moonki

Thank you message, mkjung9980.

My force plate can measure reaction force, moment, and COP data.
So, I challenge to use my data.
But, I received error message.
What should I do?

My AnyBody is AMMR1.5 and AMS5.2.

I beg your kindness.