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hello:
when i run the CMC tool,the follow errors always occur:
CMC.computeControls: t = 0.03
CMC::computeControls WARNING- small force range for semimem_r (0 to 0)

SimTK Exception thrown at interiorpointoptimizer.cpp:264:
Optimizer failed: Ipopt: Infeasible problem detected (status 2)
OPTIMIZATION FAILED...


CMC.computeControls: ERROR- Optimizer could not find a solution.
Unable to find a feasible solution at time = 0.03.
Model cannot generate the forces necessary to achieve the target acceleration.
Possible issues: 1. not all model degrees-of-freedom are actuated,
2. there are tracking tasks for locked coordinates, and/or
3. there are unnecessary control constraints on reserve/residual actuators.
The rra residual is in the range of threshold values.I use the 2392model file(task,actuator,controlconstraints)and try to increase the excitation of reserve and residual actuators,but still fail .
thanks a lot

Hi-

The CMC algorithm cannot find a solution at t=0.03. Basically, there isn't enough force to achieve the target accelerations (what CMC is trying to track). There are a number of reasons why this could be;

1. not all model degrees-of-freedom are actuated,
2. there are tracking tasks for locked coordinates, and/or
3. there are unnecessary control constraints on reserve/residual actuators.

You should check all of the above is taken into account.

-J

Thank you for your reply
I don't seem to have made the above mistakes
I used the file in the example, each degree of freedom has a residual actuator, and the range in the control constraints file is set to be large, but it still fails. I think if the muscle force doesn't produce enough acceleration, isn't there a residual actuator?Why does it fail directly?Anything else to be noticed?

Best wishes