How to read C3D file

Main Forum
1

Hi AnyBody support,

I want to use C3D files of running that were captured with OptiTrack and analyzed with venus(software of Japanese company).
I used “GaitFullBody” and I practiced “MotionAndParameterOptimization”,
but error " Parameter has an invalid value for this interpolation; extrapolations are not allowed." was indicated.

I upload the file for “TUT”.
AMS is ver5.1 and AMMR is ver 1.4.
Please tell me the misstake.

I beg your kindness.
Akira

2

Hi Akira,

  1. First, your first and last offset frame numbers are bigger than the total number of frames in the c3d file. This does not make sense!

  2. And the initial values of some markers are totally wrong. This may disturb the solving of kinematics.

Here attached please find my modified version of your model.

Best regards,
Moonki

3

Hi Moonki,
Thank you for your message.

You said initial values of some markers are wrong.
So I checked values by C3DEditor.
For example, I checked first frame values of RTHI(=Point30),
but these values were different that you modified values.
I don’t know why you could find this initial values of some markers.

I beg your kindness.
Akira

4

Hi Akira,

In the ‘ModelSetup.any’ file in your model you can change the locations of the markers attached on the human model.

Those values are relative locations with respect to the local coordinate system of human segments. So those values should be different from the global locations of the markers in the C3D file.

So I had to adjust the locations of those markers manually by looking them on the screen.

Best regards,
Moonki

5

Hi Moonki,
Thank you for your message.
I refer to your modified model and modified the location of markers.
But error “ERROR(OBJ.FILE1) : C:/U…s/d…5/D…p/T…y/A…n/E…s/G…2/JointsAndDriversOptimized.any : JntDriverTrunk.FileName : Problem with file : C:\Users\dyna105\Desktop\TUT_AnyBody\Application\Examples\GaitFullBody_TUT_With_Force_arimatu_005_2\arimatsu_0050_s-output-euler-trunk.txt :
The data file does not exist.Model loading skipped” was indicated.
What should I do outside of change the initial values of marker in ModelSetUp.any?
I upload the file for “GaitFullBody_TUT”.
AMS is ver5.1 and AMMR is ver 1.4.
Please tell me the mistake.
I beg your kindness,
Akira

6

Hi Akira,

You should run MotionAndParameterOptimizationModel process again first.

Then you could generate that missing file.

After that please try to run InverseDynamicModel process.

Best regards,
Moonki

7

Hi Moonki,

Thank you for your message.

I could run InverseDynamicModel process by grace of your help.

I beg your kindness,
Akira