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Dear All,

I ran CMC analysis on a full body model, specifically:
1. To simplify the anslysis and make clear and investigate whether failure of CMC analysis is related to factors other than muscles, all muscles of the model are deleted.
2. Reserve torques are defined for all coordinates

The reuslts show that
1. For some analysis in which only one coordinate has locomotion, the CMC (muscles are not deleted) ran sucessfully; yet, For some analysis in which all coordinates (33) has locomotion, the CMC ananlysis failed even if muscles are deleted.
2. Also, it was found that the failure time percentage is related to setting of amplitude of reserve torque.

May you help to suggest what might be the causes of failure? and how to fix?

Best regards,
Yuan

Hi, if muscles are deleted, you need strong actuators (high optimal force). Otherwise, the required forces/moments can not be produced at joints. If the muscles exist, CMC may fail again because the muscles+actuator couple is not strong enough. You can fix it by increasing the optimal force of the reserve actuator a little bit (CMCTroubleshooting); increasing the max isometric force of muscles would help as well.