Functional overview

[tomvanwouwe1992]

INPUT

• OpenSim model
• List of inverse kinematics (.sto files)
• List of muscle fiber length data (.sto files)
• Optional: List of EMG (.sto files)

SETTINGS

• Parameters to estimate: only tendon stiffness -- only slack length & optimal fiber length -- all previous
• For which muscles to couple activations
• Type of coupling (waveform or maximal difference)
• Bounds on parameters (tendon stiffness and/or optimal fiber length)

CONSTRAINTS

• Track ID torques
• Bounds on parameters (provided)
• Coupling between muscles activations (waveform or maximal difference)
• Coupling between bounds optimal fiber length and bounds slack length (Antoine?)

COST FUNCTION

• Reserve actuators (normalized; /dof)
• EMG tracking ((act_exp - act_sim); /nMuscles_EMG)
• US tracking (normalise (lm_exp-lm_sim)/(lm_opt_generic); /nMuscles_tracked)
• Effort (activations; /nMuscles)
• Regularization

[MaartenAfschrift]

A few comments: 1) Weights objective function as input argument ? 2) List of ID is needed as input as well (I would remove the option to give external loads as input) 3) Settings: bounds on activations/excitations as well (this might be useful for the passive trials)

Implementation: 4) Use lmtilde as a state in the case ultrasound data is provided, otherwise use Ftilde as a state.

Questions: 5) implicit or explicit activations dynamics ?