Taekwondo

Main Forum
1

Hey Moonki,
as I said I gonna upload a Taekwondo move. (a very simple kick which is called YOP). As you will see up to now I did not use all marker (captured by our system) for driving the model. What do you say? I wanna look at the joint loading of the different spine segments. Joint moments look very small to me compared to literature and previous studies at our institute. Feel free to “play” a little bit with the model. I would be very happy for some suggestions from your side.

Regards,
Jo

P.S. I am using AMMR 1.5.1, and in the folder it is the gaitfullbody model.

2

Hi Johannes,

I’ve tried to test and adjust marker setup for your model.
Please see the attachment.

Could you tell us which values your are investigating in detail?

And if you have any reference for spine joint moments, could you provide us some information?

Best regards,
Moonki

3

Thank you Moonki,
could you tell what you changed? wasn’t that much, was it? In the next days i gonna send you another movement incl reference loadings we would expect in special joints (L5/sacr for example). I sent you a movement we don’t have any references for. My expectations are based on a dropjump (simple movement), my fault…

Best regards,
jo

4

Hi Johannes,

I just tried to use the frame offset values to cut some frames from beginning.

And I increase the weight factors of the markers on pelvis segment.

You can just upload your model here in this forum.
You don’t need to send them to me. :slight_smile:

Best regards,
Moonki

5

Hello Moonki,
please find attached a Model including a dropjump. I have some problems with the footmarker but do not know why. Maybe you can have a short look at it. Never the less invers dynamics worked and I got some joint reaction forces and moments. I found joint forces and moments between L5-s1 respectively pelvis and scrum which are very low (especially the moments).

Force(L5-s1) (dist-prox) = 4300 N
Force(L5-s1) (med-lat) = 43 N
Force(L5-s1) (ant-post) = 920 N

Moment (s1-p)(flex-ex) = 1,2 Nm
Moment(s1-p) (axial) = -0,8 Nm
Moment(s1-p) (lateral) = 50 Nm

In another study (a few years ago) we found compressionforces in L5/S1 of about 15xbodyweight which would be over 10.000 N…

How can i get the moments between L5_S1 and respectively all other lumbal joints! Can’t be to difficult I just can’t figuere it out by my self…

GaitFullBody is the models name

6

sorry, forgot the file, here it is,

best regards
jo

7

finally it worked

8

Hi Johannes,

Attached please find my modified version of your model.
But there is not much change here. I only tried to adjust the marker definitions. So maybe you can’t fine any different between this and your version.

  1. Also I could find the the L5-S1 reaction force(prox-dist) values are slightly less than 5000N. But you think that it is too lower than your reference. Can you let us know which kind of published reference you are using right now?

  2. I think you have to define your own AnyForceMomentMeasure or AnyForceMomentMeasure2 class instance to get the moment between L5 and S1. You can refer to ‘\AMMR\Body\AAUHuman\LegTD\LegMoments.any’ file to see how you can use those classes.

Best regards,
Moonki

9

Hey Moonki,
thanks for having a look at my model. I gonna modify it as you said to get moments between all lumbar spine segments. For the next weeks I will be out of the office, but I after that I will let you know how it worked out.

Until now i did not use the shoulder rythm, because even with over head movement it looked better without. when would you recon it would be useful to use?

Best regards,
Jo

10

Hi Johannes,

  1. I can’t tell exactly when the shoulder rhythm should be used or not. It depends on your motion capture info.

  2. You don’t need to report us how it will work. No news is good news. :slight_smile:

Best regards,
Moonki

11

Hi Moonki,
at the Moment I’m working on the the moment classes you have mentionend above.

But while creating an simple output file I came to a problem. My own class ‘MomentsOutsputs’ won’t work and I can’t figure out why. It says BodyModel can’t be found but why?

Would be very nice if you could have a quick look at it.

Best regards
Jo

12

JOhannes,

try this:

AnyFolder MomentsOutputs = {

AnyOutputFile OutputFile10 = {
FileName = Main.ModelSetup.C3DFileData.NameOfFile+"-mom.txt";
SepSign = " ";

AnyFloat L5SacrumLateralMoment = Main.Studies.HumanModel.BodyModel.SelectedOutput.Trunk.JointMomentMeasure.L5SacrumLateralMoment;

};
};