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Hi all,

Can someone explain the function 'Excluded Forces' in Inversy Dynamics Setup?
I have test four options: 1) All; 2) Muscles; 3) Other Forces (expressionbasedbushings in my model); 4) none
The moments for option 1 and 2 are a little different, the difference is moment caused by bushings.
The moments for option 3 and 4 seem unrealistic, they are so large (10^4 level).

Does anyone know why?

Thanks,
Chaofei

Hi Chaofei,

During ID you may want to evaluate the generalized forces required to track the experimental data. Since muscle are also passive elements, they will apply some level of force on the skeletal system despite not being activated. Typically, only muscles are excluded, but the tool permits you to exclude other forces too.

Regards

Hi Dimitar,

Thanks! Nice to hear from you again.

I wonder why it cause unrealistic moment (very large) when excludes other forces or none?

If I run ID via GUI, whatever it excludes (all, muscles, other forces), the results are the same. it seems the default option for GUI is exclude muscles, and you can't change that.
And if I run ID via Matlab API, the moment will change with force_exclude options as I describe in the question.

Chaofei