Problem in Inverse dynamics

Hi, AnyBody supporters,

I have been trying to analyze this program.

This program could analyze running motion from Inverse dynamics.

But, Output of Inverse dynamics wasn’t computed in landing period of late.

Please find any solution for this problem.

I beg your kindness.

Takanao

Hi Takanao,

I think that you used the wrong direction of gravity vector.

Because the Z-axis is normal to the ground, you should set the gravity vector for InverseDynamicsStudy as follows:
Gravity ={0, 0, -9.81};

Please try again with this.

Best regards,
Moonki

Hi, Moonki,

Thank you for your message.

I tried to change : Gravity={0.0, -9.81, 0.0} to Gravity={0.0 , 0.0, -9.81}.

But, Output of Inverse dynamics study wasn’t computed in the last landing period.

Although I could read force plate data to this program, the reaction force and moment became 0 in the last landing period.

Best regards

Takanao

Hi,

I don’t understand what you mean about the last landing period.

I would ask of you some questions.

  1. How many force plates did you use for your experiment?

  2. If you used more than 2 force plates, then I think you have to modify ‘ForcePlateType3AutoDetection_TUT.any’ file to control the location of different force plates.

  3. Also, if you used more than 2 force plates, then also you have to modify ‘EnvironmentAutoDetection.any’ file two create more force plate objects.

In the current setting of your model, there is only one force plate.

Please check again carefully and modify your models.

Best regards,
Moonki

Hi,

I’m sorry , My explanation was insufficient information.

My experiment used a force plate.

Mocap date was synchronized with force plate data.

From 0.1395(s) to 0.3395(s) , ground reaction force was reflected in output of Inverse dynamics study.

But, from o.340(s) to 0.4035(s), ground reaction force wasn’t reflected in output.

Please find any solution for this problem.

Best regards,

Takanao

Hi,

Try to modify your ‘EnvironmentAutoDetection.any’ file like this:

ForcePlateType3AutoDetection Plate1 (
PlateName = Plate1,
Folder =Main.ModelSetup.C3DFileData,
Limb1=  .HumanModelRef.Right.Leg.Seg.Foot,
Limb2=  .HumanModelRef.Left.Leg.Seg.Foot,
No=0,
VerticalDirection ="Z",
HeightTolerance=[b]0.1[/b],
VelThreshold=[b]3.5[/b],
ForcePlateDataInputFile = "kobayashi_003_calibrationdata.txt",
FootPresent=HumanModelPresent)
={
};

Best regards,
Moonki