Activation dynamics of Schutte muscle model

[Saurabh Kothari]

Hi All,

I was looking through the source code of following muscle models in OpenSim:

1) Delp1990Muscle_Deprecated
2) Schutte1993Muscle_Deprecated

In both the models, the activation dynamics is described as follows:
If u(t) >= a(t),
da/dt = [u(t) - a(t)] * [k1*u(t) + k2]

else
da/dt = k2 * [u(t) - a(t)]

I would like to understand how constants k1 and k2 are related to activation and deactivation time constants (Tact and Tdeact).

Thanks,
Saurabh

[Thomas Uchida]

Please see the "First-Order Activation Dynamics" page in the documentation: https://simtk-confluence.stanford.edu:8 ... n+Dynamics.