error during inverse dynamics analysis

Hi, my name is Teppei from Japan.
I started using AnyBody last summer, I’m still beginner.
This is my first Thread so maybe there’s many mistake in my English.
But plese give me everyone’s help.

My AnyBody’s version is 4.2, I need help to solve my problem.

I wan’t to solve the following error message.


  1. InverseDynamics (Operation: Main.Study.InverseDynamics):
    0.0) PreOperation (Operation: Main.Study.InverseDynamics.PreOperation):
    0.0) InitialConditions (Operation: Main.Study.InitialConditions):
    0.0) …Design variables have been updated.
    0.1) …Load time positions have been re-established.
    0.2) …Kinematic analysis completed. The kinematic constraints have been resolved.
    0.3) …Initial conditions are fully updated.
  2. Inverse dynamic analysis…
    ERROR(OBJ.MCH.MUS4) : //K…2/h…2/2…x/・.)/・.ス/A…y/A…1/2…9/A…n/E…s/F…e/FreePosture.Main.any : Study.InverseDynamics : Muscle recruitment solver : solver aborted due to singular KKT matrix

“What I did”
Insert ACL to freePosture.any model (file:20110119) by consulting LowerExtremityModel.any (file:LEM20101220)

“What I want to do”
Inverse Dynamics

I attach my model’s files (maybe, because this is my first time to post)

Plese help me to solve this problem.

thank you.

Hi Teppei,
welcome to the forum.
This error typically indicates that some degrees of freedom are not carried. The reason could be missing muscles for a certain motion, missing reactions in a joint or to ground. What is your strategy for the knee joint. I just had a brief look, but it seems you are missing some reactions in the joint. (The normal knee joint carries 5 DoF).
Best regards,
Sebastian

P.S.
Please consider writing in the Professional Forum as AnyBody people usually not respond in the self-supported forum.