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changing fiber force length curve setting

Posted: Tue Feb 17, 2015 1:49 pm
by mohamadmah111
Hello.I was trying to change some of fiber force length curve settings such as curviness in millard model,but it is impossible.Can anybody help me how to do this? Thanks a lot

Re: changing fiber force length curve setting

Posted: Mon Feb 23, 2015 2:39 pm
by jimmy
Hi Mohamad,

How were you trying to change the curves? the Millard Model has those properties exposed and it can be changed in the xml or by using the API.

Cheers,
-James

Re: changing fiber force length curve setting

Posted: Tue Feb 24, 2015 3:17 am
by mohamadmah111
Hello James.
I was trying to change the properties in the program.It was impossible.Then i saw your comment.I tried to change .XML file setting.When i changed the setting now it is impossible to open the model file.
The error is :
Exception caught in RightMuscle::buildMuscle()
SimTK Exception thrown at FiberForceLengthCurve.cpp:155:
Error detected by Simbody method FiberForceLengthCurve::ensureCurveUpToDate(): RightMuscle_FiberForceLengthCurve: Optional parameters stiffnessAtLowForce,

Thank you

Re: changing fiber force length curve setting

Posted: Thu Feb 26, 2015 3:29 pm
by aseth
Post the parameters and the values you are trying to apply.

Re: changing fiber force length curve setting

Posted: Fri Feb 27, 2015 8:30 am
by mohamadmah111
For example:

Stiffness at low force:2
Stiffness at one norm force:0.5
curviness:0.8
Thank You

Re: changing fiber force length curve setting

Posted: Sun Mar 29, 2015 11:02 am
by mohamadmah111
Hello Dear seth
I asked a question in opensim forum and you asked to give you the parameters.But since then you didn't reply me back.I wanted asked if you could solve my problem and help me.

Best Regards

Re: changing fiber force length curve setting

Posted: Tue Mar 31, 2015 2:32 pm
by jimmy
Below is the code snippet where the error is generated. Note:
stiffnessAtOneNormForce, and curviness must either all be set or all be empty.

Code: Select all

else {
        // Ensure that the reference curve is being used to populate either all
        // optional properties or none of them; otherwise, there would be an
        // inconsistency in the computed curve and it wouldn't reflect the
        // reference curve.

        SimTK_ERRCHK1_ALWAYS(false,
            "FiberForceLengthCurve::ensureCurveUpToDate()",
            "%s: Optional parameters stiffnessAtLowForce, "
            "stiffnessAtOneNormForce, and curviness must either all be set or "
            "all be empty.", getName().c_str());
Link to the source code;
https://github.com/opensim-org/opensim- ... hCurve.cpp