Scaling of shoulder width

Main Forum
1

Hej

We are modelling a motion which involves a lot of motion in the shoulder region. We are using the MoCap model and uses a full-body set of markers. We have understood that the scaling of the shoulder width is made from size of the pelvis width. We have have women from 1.50-1.70 participating in the study and the present scaling makes the shoulders too wide. Where in the code structure can we find the value for changing the relation between pelvis and shoulder width?

Kind regards,
Marie

2

Dear Marie,

If you see the ‘AMMR\Body\AAUHuman\Scaling\ScalingLengthMassFat.any’ file which is used in the MoCapModel, you can find the following section:

    AnyFolder Trunk = {
      AnyVar LengthScale = (..AnthroSegmentLengths.TrunkHeight / ..StandardParameters.Trunk.Height);
      AnyVar ms = ..MassScaling.Trunk.MassScale;
      AnyVar ls = LengthScale;
      AnyFunTransform3DLin ScaleFunction = {
        ScaleMat = {{(.ms/.ls)^0.5, 0, 0},{0, .ls, 0},{0, 0, (.ms/.ls)^0.5}};
        Offset = {0,0,0};
      };
    };

Bascially the ls(LengthScale) is used for the scaling of one dimension in the trunk segment.
And ms(mass scale) will be also used with ls for the scaling of other dimensions.

If you are not happy with our trunk scaling method, then you can try to customize this section as you want.

Best regards,
Moonki