CMC error

Provide easy-to-use, extensible software for modeling, simulating, controlling, and analyzing the neuromusculoskeletal system.
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Moe Curtin
Posts: 43
Joined: Fri Oct 02, 2009 5:40 am

CMC error

Post by Moe Curtin » Wed Dec 09, 2009 10:48 am

I have just started using the CMC tool on a model and as it runs, in the message window I am getting "RKF.step: NAN in state 1 at time 0" repeatedly. The CMC execution doesn't finish, but I don't get an error message either. Would there be something obvious wrong with my model or motion file that somebody here might know about that would cause this to happen?

Thanks!

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Ayman Habib
Posts: 2235
Joined: Fri Apr 01, 2005 12:24 pm

RE: CMC error

Post by Ayman Habib » Wed Dec 09, 2009 11:53 am

Moe,

The message about "RKF.step: NAN in state X" could be benign since it could be issued while the integrator is taking trial steps (so that it backs off) not during successful integration steps.
The fact that CMC doesn't finish is troublesome though, and could be due to many reasons.
Did you try running for a shorter duration? Does it finish initialization?

Best,
-Ayman

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Moe Curtin
Posts: 43
Joined: Fri Oct 02, 2009 5:40 am

RE: CMC error

Post by Moe Curtin » Thu Dec 10, 2009 4:56 am

Hi Ayman,

It does finish computing initial states. It then says:

"Using CMC to track the specified kinematics
Integrating from 0.03 to 1"

But only executes for 0.03 and then prints results. If I start at another time e.g. 0.5, it will only go as far as 0.53 etc. Also, the time range in the motion bar at the top of the screen which originally read from 0 to 1 now reads from 0.03 to 0.03.

I am using the neck model incase anyone else has had similar issues.

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