SimTK: OpenSim: [#1191] Static optimization "states" not saving activation or fiber length

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Date:
2010-05-24 17:35

Priority:
3

State:
Open

Submitted by:
Bryant Sih (bryantsih)

Assigned to:
Ayman Habib (aymanh)

Summary:
Static optimization "states" not saving activation or fiber length

Detailed description
If I understand correctly, after running SO, the motions -> states output should be both the coordinate states (pos, vel) and actuator states (for Thelen2203Muscle: activation & fiber_length). For me, only coordinate states are output correctly. The actuator states are all set to zero. SO appears to be working because the SO output file "_activation.sto" contains the correct activation level. I've attached a simple one-muscle model (hang.osim) where the muscle suspends a block against gravity without moving (hang.mot). Running SO results in the actuator states set to zero as described (at least for me).
If I understand correctly, after running SO, the motions -> states output should be both the coordinate states (pos, vel) and actuator states (for Thelen2203Muscle: activation & fiber_length). For me, only coordinate states are output correctly. The actuator states are all set to zero. SO appears to be working because the SO output file "_activation.sto" contains the correct activation level. I've attached a simple one-muscle model (hang.osim) where the muscle suspends a block against gravity without moving (hang.mot). Running SO results in the actuator states set to zero as described (at least for me).

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Size	Name	Date	By	Download
18 KiB	Hang.zip	2010-05-24 17:35	bryantsih	Hang.zip

Field	Old Value	Date	By
category_id	100	2012-03-28 19:35	jenhicks
assigned_to	none	2012-03-28 19:35	jenhicks
summary	Static optimization "states" not saving activation or fiber length	2012-03-28 19:35	jenhicks
File Added	256: Hang.zip	2010-05-24 17:35	bryantsih

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