Shape factor for Force-Length relationships
Posted: Thu Sep 29, 2011 4:41 am
Hi!
I am trying to reproduce calculations of active and passive forces and force-length-velocity surface using the fiber length. Most of fibers during different movements have fiber length below the 'optimal_fiber_length' (for example, lower body model, Gait2354). If we use 'function representing passive force-length behavior of muscle fibers' from *.osim file, then we are not supposed to have passive force. But OpenSim Plotter shows that the passive force exists even for fiber length below optimal. Considering my experimental experience, this is reasonable.
I could not figure out how to use the shape factors for active and passive force-length relationships, and force-velocity shape factor. Perhaps, the shape factors may lead some light on my problem:
how to calculate the forces using fiber length?
Hoping to get a help,
Natalia
I am trying to reproduce calculations of active and passive forces and force-length-velocity surface using the fiber length. Most of fibers during different movements have fiber length below the 'optimal_fiber_length' (for example, lower body model, Gait2354). If we use 'function representing passive force-length behavior of muscle fibers' from *.osim file, then we are not supposed to have passive force. But OpenSim Plotter shows that the passive force exists even for fiber length below optimal. Considering my experimental experience, this is reasonable.
I could not figure out how to use the shape factors for active and passive force-length relationships, and force-velocity shape factor. Perhaps, the shape factors may lead some light on my problem:
how to calculate the forces using fiber length?
Hoping to get a help,
Natalia