OpenSim::Thelen2003Muscle Class Reference

A class implementing a SIMM muscle. More...

#include <Thelen2003Muscle.h>

Inheritance diagram for OpenSim::Thelen2003Muscle:
OpenSim::Muscle OpenSim::CustomActuator OpenSim::Actuator OpenSim::Force OpenSim::ModelComponent OpenSim::Object

List of all members.

Public Member Functions

 Thelen2003Muscle ()
 Default constructor.
 Thelen2003Muscle (const std::string &aName, double aMaxIsometricForce, double aOptimalFiberLength, double aTendonSlackLength, double aPennationAngle)
 Constructor.
 Thelen2003Muscle (const Thelen2003Muscle &aMuscle)
 Copy constructor.
virtual ~Thelen2003Muscle ()
 Destructor.
virtual Object * copy () const
 Copy this muscle point and return a pointer to the copy.
Thelen2003Muscle & operator= (const Thelen2003Muscle &aMuscle)
 Assignment operator.
void copyData (const Thelen2003Muscle &aMuscle)
 Copy data members from one Thelen2003Muscle to another.
virtual void copyPropertyValues (Actuator &aActuator)
 Copy the property values from another actuator, which may not be a Thelen2003Muscle.
virtual void initStateCache (SimTK::State &s, SimTK::SubsystemIndex subsystemIndex, Model &model)
 allocate and initialize the SimTK state for this acuator.
virtual double getMaxIsometricForce () const
 getMaxIsometricForce needs to be overridden by derived classes to be usable
virtual double getOptimalFiberLength () const
virtual double getTendonSlackLength () const
virtual double getPennationAngleAtOptimalFiberLength () const
virtual double getActivationTimeConstant () const
virtual double getDeactivationTimeConstant () const
virtual double getVmax () const
virtual double getVmax0 () const
virtual double getFmaxTendonStrain () const
virtual double getFmaxMuscleStrain () const
virtual double getKshapeActive () const
virtual double getKshapePassive () const
virtual double getDamping () const
virtual double getAf () const
virtual double getFlen () const
virtual bool setActivationTimeConstant (double aActivationTimeConstant)
 Set the time constant for ramping up of muscle force.
virtual bool setDeactivationTimeConstant (double aDeactivationTimeConstant)
 Set the time constant for ramping down of muscle force.
virtual bool setMaxIsometricForce (double aMaxIsometricForce)
 Set the maximum isometric force that the fibers can generate.
virtual bool setOptimalFiberLength (double aOptimalFiberLength)
 Set the optimal length of the muscle fibers.
virtual bool setTendonSlackLength (double aTendonSlackLength)
 Set the resting length of the tendon.
virtual bool setPennationAngle (double aPennationAngle)
 Set the angle between tendon and fibers at optimal fiber length.
virtual bool setVmax (double aVmax)
 Set the maximum contraction velocity of the fibers, in optimal fiber lengths per second.
virtual bool setVmax0 (double aVmax0)
 Set the maximum contraction velocity at low activation of the fibers, in optimal fiber lengths per second.
virtual bool setFmaxTendonStrain (double aFmaxTendonStrain)
 Set the tendon strain due to maximum isometric muscle force.
virtual bool setFmaxMuscleStrain (double aFmaxMuscleStrain)
 Set the passive muscle strain due to maximum isometric muscle force.
virtual bool setKshapeActive (double aKShapeActive)
 Set the shape factor for Gaussian active muscle force-length relationship.
virtual bool setKshapePassive (double aKshapePassive)
 Set the shape factor for Gaussian passive muscle force-length relationship.
virtual bool setDamping (double aDamping)
 Set the damping factor related to maximum contraction velocity.
virtual bool setAf (double aAf)
 Set the force-velocity shape factor.
virtual bool setFlen (double aFlen)
 Set the maximum normalized lengthening force.
virtual double getPennationAngle (const SimTK::State &s) const
 Get the current pennation angle of the muscle fiber(s).
virtual double getNormalizedFiberLength (const SimTK::State &s) const
 Get the normalized length of the muscle fiber(s).
virtual double getPassiveFiberForce (const SimTK::State &s) const
 Get the passive force generated by the muscle fibers.
virtual double getStress (const SimTK::State &s) const
 Get the stress in this actuator.
virtual double getActivation (const SimTK::State &s) const
virtual void setActivation (SimTK::State &s, double activation) const
virtual double getActivationDeriv (const SimTK::State &s) const
virtual void setActivationDeriv (const SimTK::State &s, double activationDeriv) const
virtual double getFiberLength (const SimTK::State &s) const
virtual void setFiberLength (SimTK::State &s, double fiberLength) const
virtual double getFiberLengthDeriv (const SimTK::State &s) const
virtual void setFiberLengthDeriv (const SimTK::State &s, double fiberLengthDeriv) const
virtual void setTendonForce (const SimTK::State &s, double aForce) const
virtual double getTendonForce (const SimTK::State &s) const
virtual void setActiveForce (const SimTK::State &s, double aForce) const
virtual double getActiveForce (const SimTK::State &s) const
virtual void setPassiveForce (const SimTK::State &s, double aForce) const
virtual double getPassiveForce (const SimTK::State &s) const
virtual void computeStateDerivatives (const SimTK::State &s)
 Compute the derivatives of the muscle states.
virtual void computeEquilibrium (SimTK::State &s) const
 Compute the equilibrium states.
virtual double computeActuation (const SimTK::State &s) const
 Compute the actuation for the muscle.
double calcTendonForce (const SimTK::State &s, double aNormTendonLength) const
 From cmg_dt.c - calc_tendon_force_dt.
double calcPassiveForce (const SimTK::State &s, double aNormFiberLength) const
 From gmc.dt.c - calc_passive_fiber_force_dt.
double calcActiveForce (const SimTK::State &s, double aNormFiberLength) const
 From gmc.dt.c - calc_active_force_dt.
double calcFiberVelocity (const SimTK::State &s, double aActivation, double aActiveForce, double aVelocityDependentForce) const
 From gmc_dt.c - calc_norm_fiber_velocity_dt.
virtual double computeIsometricForce (SimTK::State &s, double activation) const
 Find the force produced by an actuator (the musculotendon unit), assuming static equilibrium.
virtual double computeIsokineticForceAssumingInfinitelyStiffTendon (SimTK::State &s, double aActivation)
 Find the force produced by muscle under isokinetic conditions assuming an infinitely stiff tendon.
virtual void postScale (const SimTK::State &s, const ScaleSet &aScaleSet)
 Perform computations that need to happen after the muscle is scaled.
virtual void scale (const SimTK::State &s, const ScaleSet &aScaleSet)
 Scale the muscle.
virtual void equilibrate (SimTK::State &state) const
virtual void setup (Model &aModel)
 Perform some set up functions that happen after the object has been deserialized or copied.
 OPENSIM_DECLARE_DERIVED (Thelen2003Muscle, Actuator)

Protected Attributes

PropertyDbl _maxIsometricForceProp
 Maximum isometric force that the fibers can generate.
double & _maxIsometricForce
PropertyDbl _optimalFiberLengthProp
 Optimal length of the muscle fibers.
double & _optimalFiberLength
PropertyDbl _tendonSlackLengthProp
 Resting length of the tendon.
double & _tendonSlackLength
PropertyDbl _pennationAngleProp
 Angle between tendon and fibers at optimal fiber length.
double & _pennationAngle
PropertyDbl _activationTimeConstantProp
 Activation time constant.
double & _activationTimeConstant
PropertyDbl _deactivationTimeConstantProp
 Deactivation time constant.
double & _deactivationTimeConstant
PropertyDbl _vmaxProp
 Max contraction velocity full activation in fiber lengths per second.
double & _vmax
PropertyDbl _vmax0Prop
 Max contraction velocity at low activation.
double & _vmax0
PropertyDbl _fmaxTendonStrainProp
 Tendon strain due to maximum isometric muscle force.
double & _fmaxTendonStrain
PropertyDbl _fmaxMuscleStrainProp
 Passive muscle strain due to maximum isometric muscle force.
double & _fmaxMuscleStrain
PropertyDbl _kShapeActiveProp
 Shape factor for Gaussian active muscle force-length relationship.
double & _kShapeActive
PropertyDbl _kShapePassiveProp
 Exponential shape factor for passive force-length relationship.
double & _kShapePassive
PropertyDbl _dampingProp
 Passive damping included in the force-velocity relationship.
double & _damping
PropertyDbl _afProp
 Force-velocity shape factor.
double & _af
PropertyDbl _flenProp
 Maximum normalized lengthening force.
double & _flen
SimTK::CacheEntryIndex _tendonForceIndex
 indexes for Forces in various components
SimTK::CacheEntryIndex _activeForceIndex
SimTK::CacheEntryIndex _passiveForceIndex

Static Protected Attributes

static const int STATE_ACTIVATION = 0
static const int STATE_FIBER_LENGTH = 1

Detailed Description

A class implementing a SIMM muscle.

Author:
Peter Loan
Version:
1.0

Constructor & Destructor Documentation

Thelen2003Muscle::Thelen2003Muscle (  ) 

Default constructor.

Thelen2003Muscle::Thelen2003Muscle ( const std::string &  aName,
double  aMaxIsometricForce,
double  aOptimalFiberLength,
double  aTendonSlackLength,
double  aPennationAngle 
)

Constructor.

Thelen2003Muscle::Thelen2003Muscle ( const Thelen2003Muscle &  aMuscle  ) 

Copy constructor.

Parameters:
aMuscle Thelen2003Muscle to be copied.
Thelen2003Muscle::~Thelen2003Muscle (  )  [virtual]

Destructor.

Member Function Documentation

double Thelen2003Muscle::calcActiveForce ( const SimTK::State &  s,
double  aNormFiberLength 
) const

From gmc.dt.c - calc_active_force_dt.

CALC_ACTIVE_FORCE_DT: this routine calculates the active component of force in the muscle fibers. It uses the current fiber length to interpolate the active force-length curve - described by Gaussian curve as in Thelen, JBME 2003 *

Parameters:
aNormFiberLength Normalized length of the muscle fiber.
Returns:
The active force in the muscle fibers.
double Thelen2003Muscle::calcFiberVelocity ( const SimTK::State &  s,
double  aActivation,
double  aActiveForce,
double  aVelocityDependentForce 
) const

From gmc_dt.c - calc_norm_fiber_velocity_dt.

CALC_NORM_FIBER_VELOCITY_DT: written by Darryl Thelen this routine calculates the normalized fiber velocity (scaled to Vmax) by inverting the muscle force-velocity-activation relationship (Thelen, JBME 2003) This equation is parameterized using the following dynamic parameters which must be specified in the muscle file Dynamic Parameters: damping - normalized passive damping in parallel with contractile element Af - velocity shape factor from Hill's equation Flen - Maximum normalized force when muscle is lengthening

Parameters:
aActivation Activation of the muscle.
aActiveForce Active force in the muscle fibers.
aVelocityDependentForce Force value that depends on fiber velocity.
Returns:
The velocity of the muscle fibers.
double Thelen2003Muscle::calcPassiveForce ( const SimTK::State &  s,
double  aNormFiberLength 
) const

From gmc.dt.c - calc_passive_fiber_force_dt.

CALC_PASSIVE_FIBER_FORCE_DT: written by Darryl Thelen this routine calculates the passive force in the muscle fibers using an exponential-linear function instead of cubic splines. It always returns a non-zero force for all muscle lengths This equation is parameterized using the following dynamic parameters which must be specified in the muscle file Dynamic Parameters: FmaxMuscleStrain - passive muscle strain due to the application of maximum isometric muscle force KshapePassive - exponential shape factor

The normalized force due to passive stretch is given by For L < (1+maxStrain)*Lo f/f0 = exp(ks*(L-1)/maxStrain) / exp(ks)

Parameters:
aNormFiberLength Normalized length of the muscle fiber.
Returns:
The passive force in the muscle fibers.
double Thelen2003Muscle::calcTendonForce ( const SimTK::State &  s,
double  aNormTendonLength 
) const

From cmg_dt.c - calc_tendon_force_dt.

CALC_TENDON_FORCE_DT: this routine calculates the force in tendon by finding tendon strain and using it in an exponential function (JBME 2003 - Thelen) FmaxTendonStrain - Function is parameterized by the tendon strain due to maximum isometric muscle force This should be specified as a dynamic parameter in the muscle file

Parameters:
aNormTendonLength Normalized length of the tendon.
Returns:
The force in the tendon.
double Thelen2003Muscle::computeActuation ( const SimTK::State &  s  )  const [virtual]

Compute the actuation for the muscle.

This function assumes that computeDerivatives has already been called.

This function is based on muscle_deriv_func9 from derivs.c (old pipeline code)

Reimplemented from OpenSim::Muscle.

void Thelen2003Muscle::computeEquilibrium ( SimTK::State &  s  )  const [virtual]

Compute the equilibrium states.

This method computes a fiber length for the muscle that is consistent with the muscle's activation level.

Reimplemented from OpenSim::Actuator.

double Thelen2003Muscle::computeIsokineticForceAssumingInfinitelyStiffTendon ( SimTK::State &  s,
double  aActivation 
) [virtual]

Find the force produced by muscle under isokinetic conditions assuming an infinitely stiff tendon.

That is, all the shortening velocity of the actuator (the musculotendon unit) is assumed to be due to the shortening of the muscle fibers alone. This methods calls computeIsometricForce() and so alters the internal member variables of this muscle.

Note that the current implementation approximates the effect of the force-velocity curve. It does not account for the shortening velocity when it is solving for the equilibrium length of the muscle fibers. And, a generic representation of the force-velocity curve is used (as opposed to the implicit force-velocity curve assumed by this model.

Parameters:
aActivation Activation of the muscle.
Returns:
Isokinetic force generated by the actuator.

Implements OpenSim::Muscle.

double Thelen2003Muscle::computeIsometricForce ( SimTK::State &  s,
double  aActivation 
) const [virtual]

Find the force produced by an actuator (the musculotendon unit), assuming static equilibrium.

Using the total muscle-tendon length, it finds the fiber and tendon lengths so that the forces in each match. This routine takes pennation angle into account, so its definition of static equilibrium is when tendon_force = fiber_force * cos(pennation_angle). This funcion will modify the object's values for _length, _fiberLength, _activeForce, and _passiveForce.

Parameters:
aActivation Activation of the muscle.
Returns:
The isometric force in the muscle.

Implements OpenSim::Muscle.

void Thelen2003Muscle::computeStateDerivatives ( const SimTK::State &  s  )  [virtual]

Compute the derivatives of the muscle states.

Parameters:
s system state
index 

Reimplemented from OpenSim::Actuator.

Object * Thelen2003Muscle::copy (  )  const [virtual]

Copy this muscle point and return a pointer to the copy.

The copy constructor for this class is used.

Returns:
Pointer to a copy of this Thelen2003Muscle.

Implements OpenSim::Muscle.

void Thelen2003Muscle::copyData ( const Thelen2003Muscle &  aMuscle  ) 

Copy data members from one Thelen2003Muscle to another.

Parameters:
aMuscle Thelen2003Muscle to be copied.

Reimplemented from OpenSim::Muscle.

void Thelen2003Muscle::copyPropertyValues ( Actuator &  aActuator  )  [virtual]

Copy the property values from another actuator, which may not be a Thelen2003Muscle.

Parameters:
aActuator Actuator to copy property values from.
void Thelen2003Muscle::equilibrate ( SimTK::State &  state  )  const [virtual]

Reimplemented from OpenSim::Muscle.

virtual double OpenSim::Thelen2003Muscle::getActivation ( const SimTK::State &  s  )  const [inline, virtual]

Implements OpenSim::Muscle.

virtual double OpenSim::Thelen2003Muscle::getActivationDeriv ( const SimTK::State &  s  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getActivationTimeConstant (  )  const [inline, virtual]
double Thelen2003Muscle::getActiveForce ( const SimTK::State &  s  )  const [virtual]
virtual double OpenSim::Thelen2003Muscle::getAf (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getDamping (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getDeactivationTimeConstant (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getFiberLength ( const SimTK::State &  s  )  const [inline, virtual]

Implements OpenSim::Muscle.

virtual double OpenSim::Thelen2003Muscle::getFiberLengthDeriv ( const SimTK::State &  s  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getFlen (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getFmaxMuscleStrain (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getFmaxTendonStrain (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getKshapeActive (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getKshapePassive (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getMaxIsometricForce (  )  const [inline, virtual]

getMaxIsometricForce needs to be overridden by derived classes to be usable

Reimplemented from OpenSim::Muscle.

double Thelen2003Muscle::getNormalizedFiberLength ( const SimTK::State &  s  )  const [virtual]

Get the normalized length of the muscle fiber(s).

This is the current fiber length(s) divided by the optimal fiber length.

Parameters:
Current length of the muscle fiber(s).

Implements OpenSim::Muscle.

virtual double OpenSim::Thelen2003Muscle::getOptimalFiberLength (  )  const [inline, virtual]
double Thelen2003Muscle::getPassiveFiberForce ( const SimTK::State &  s  )  const [virtual]

Get the passive force generated by the muscle fibers.

Parameters:
Current passive force of the muscle fiber(s).

Implements OpenSim::Muscle.

double Thelen2003Muscle::getPassiveForce ( const SimTK::State &  s  )  const [virtual]
double Thelen2003Muscle::getPennationAngle ( const SimTK::State &  s  )  const [virtual]

Get the current pennation angle of the muscle fiber(s).

Parameters:
Pennation angle.

Implements OpenSim::Muscle.

virtual double OpenSim::Thelen2003Muscle::getPennationAngleAtOptimalFiberLength (  )  const [inline, virtual]

Implements OpenSim::Muscle.

double Thelen2003Muscle::getStress ( const SimTK::State &  s  )  const [virtual]

Get the stress in this actuator.

It is calculated as the force divided by the maximum isometric force (which is proportional to its area).

Reimplemented from OpenSim::Actuator.

double Thelen2003Muscle::getTendonForce ( const SimTK::State &  s  )  const [virtual]
virtual double OpenSim::Thelen2003Muscle::getTendonSlackLength (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getVmax (  )  const [inline, virtual]
virtual double OpenSim::Thelen2003Muscle::getVmax0 (  )  const [inline, virtual]
void Thelen2003Muscle::initStateCache ( SimTK::State &  s,
SimTK::SubsystemIndex  subsystemIndex,
Model &  model 
) [virtual]

allocate and initialize the SimTK state for this acuator.

Reimplemented from OpenSim::Muscle.

OpenSim::Thelen2003Muscle::OPENSIM_DECLARE_DERIVED ( Thelen2003Muscle  ,
Actuator   
)

Reimplemented from OpenSim::CustomActuator.

Thelen2003Muscle & Thelen2003Muscle::operator= ( const Thelen2003Muscle &  aMuscle  ) 

Assignment operator.

Returns:
Reference to this object.

Reimplemented from OpenSim::Muscle.

void Thelen2003Muscle::postScale ( const SimTK::State &  s,
const ScaleSet &  aScaleSet 
) [virtual]

Perform computations that need to happen after the muscle is scaled.

For this object, that entails comparing the musculotendon length before and after scaling, and scaling some of the force-generating properties a proportional amount.

Parameters:
aScaleSet XYZ scale factors for the bodies.

Reimplemented from OpenSim::Muscle.

void Thelen2003Muscle::scale ( const SimTK::State &  s,
const ScaleSet &  aScaleSet 
) [virtual]

Scale the muscle.

Parameters:
aScaleSet XYZ scale factors for the bodies
Returns:
Whether or not the muscle was scaled successfully

Reimplemented from OpenSim::Muscle.

virtual void OpenSim::Thelen2003Muscle::setActivation ( SimTK::State &  s,
double  activation 
) const [inline, virtual]

Implements OpenSim::Muscle.

virtual void OpenSim::Thelen2003Muscle::setActivationDeriv ( const SimTK::State &  s,
double  activationDeriv 
) const [inline, virtual]
bool Thelen2003Muscle::setActivationTimeConstant ( double  aActivationTimeConstant  )  [virtual]

Set the time constant for ramping up of muscle force.

Parameters:
aActivationTimeConstant The time constant for ramping up of muscle force.
Returns:
Whether the time constant was successfully changed.
void Thelen2003Muscle::setActiveForce ( const SimTK::State &  s,
double  aForce 
) const [virtual]
bool Thelen2003Muscle::setAf ( double  aAf  )  [virtual]

Set the force-velocity shape factor.

Parameters:
aAf The force-velocity shape factor.
Returns:
Whether the shape factor was successfully changed.
bool Thelen2003Muscle::setDamping ( double  aDamping  )  [virtual]

Set the damping factor related to maximum contraction velocity.

Parameters:
aDamping The damping factor related to maximum contraction velocity.
Returns:
Whether the damping factor was successfully changed.
bool Thelen2003Muscle::setDeactivationTimeConstant ( double  aDeactivationTimeConstant  )  [virtual]

Set the time constant for ramping down of muscle force.

Parameters:
aDeactivationTimeConstant The time constant for ramping down of muscle force.
Returns:
Whether the time constant was successfully changed.
virtual void OpenSim::Thelen2003Muscle::setFiberLength ( SimTK::State &  s,
double  fiberLength 
) const [inline, virtual]

Implements OpenSim::Muscle.

virtual void OpenSim::Thelen2003Muscle::setFiberLengthDeriv ( const SimTK::State &  s,
double  fiberLengthDeriv 
) const [inline, virtual]
bool Thelen2003Muscle::setFlen ( double  aFlen  )  [virtual]

Set the maximum normalized lengthening force.

Parameters:
aFlen The maximum normalized lengthening force.
Returns:
Whether the maximum normalized lengthening force was successfully changed.
bool Thelen2003Muscle::setFmaxMuscleStrain ( double  aFmaxMuscleStrain  )  [virtual]

Set the passive muscle strain due to maximum isometric muscle force.

Parameters:
aFmaxMuscleStrain The passive muscle strain due to maximum isometric muscle force.
Returns:
Whether the passive muscle strain was successfully changed.
bool Thelen2003Muscle::setFmaxTendonStrain ( double  aFmaxTendonStrain  )  [virtual]

Set the tendon strain due to maximum isometric muscle force.

Parameters:
aFmaxTendonStrain The tendon strain due to maximum isometric muscle force.
Returns:
Whether the tendon strain was successfully changed.
bool Thelen2003Muscle::setKshapeActive ( double  aKShapeActive  )  [virtual]

Set the shape factor for Gaussian active muscle force-length relationship.

Parameters:
aKShapeActive The shape factor for Gaussian active muscle force-length relationship.
Returns:
Whether the shape factor was successfully changed.
bool Thelen2003Muscle::setKshapePassive ( double  aKshapePassive  )  [virtual]

Set the shape factor for Gaussian passive muscle force-length relationship.

Parameters:
aKshapePassive The shape factor for Gaussian passive muscle force-length relationship.
Returns:
Whether the shape factor was successfully changed.
bool Thelen2003Muscle::setMaxIsometricForce ( double  aMaxIsometricForce  )  [virtual]

Set the maximum isometric force that the fibers can generate.

Parameters:
aMaxIsometricForce The maximum isometric force that the fibers can generate.
Returns:
Whether the maximum isometric force was successfully changed.
bool Thelen2003Muscle::setOptimalFiberLength ( double  aOptimalFiberLength  )  [virtual]

Set the optimal length of the muscle fibers.

Parameters:
aOptimalFiberLength The optimal length of the muscle fibers.
Returns:
Whether the optimal length was successfully changed.
void Thelen2003Muscle::setPassiveForce ( const SimTK::State &  s,
double  aForce 
) const [virtual]
bool Thelen2003Muscle::setPennationAngle ( double  aPennationAngle  )  [virtual]

Set the angle between tendon and fibers at optimal fiber length.

Parameters:
aPennationAngle The angle between tendon and fibers at optimal fiber length.
Returns:
Whether the angle was successfully changed.
void Thelen2003Muscle::setTendonForce ( const SimTK::State &  s,
double  aForce 
) const [virtual]
bool Thelen2003Muscle::setTendonSlackLength ( double  aTendonSlackLength  )  [virtual]

Set the resting length of the tendon.

Parameters:
aTendonSlackLength The resting length of the tendon.
Returns:
Whether the resting length was successfully changed.
void Thelen2003Muscle::setup ( Model &  aModel  )  [virtual]

Perform some set up functions that happen after the object has been deserialized or copied.

Parameters:
aModel model containing this Thelen2003Muscle.

Reimplemented from OpenSim::Muscle.

bool Thelen2003Muscle::setVmax ( double  aVmax  )  [virtual]

Set the maximum contraction velocity of the fibers, in optimal fiber lengths per second.

Parameters:
aVmax The maximum contraction velocity of the fibers, in optimal fiber lengths per second.
Returns:
Whether the maximum contraction velocity was successfully changed.
bool Thelen2003Muscle::setVmax0 ( double  aVmax0  )  [virtual]

Set the maximum contraction velocity at low activation of the fibers, in optimal fiber lengths per second.

Parameters:
aVmax The maximum contraction velocity at low activation of the fibers, in optimal fiber lengths per second.
Returns:
Whether the maximum contraction velocity was successfully changed.

Member Data Documentation

double& OpenSim::Thelen2003Muscle::_activationTimeConstant [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_activationTimeConstantProp [protected]

Activation time constant.

SimTK::CacheEntryIndex OpenSim::Thelen2003Muscle::_activeForceIndex [protected]
double& OpenSim::Thelen2003Muscle::_af [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_afProp [protected]

Force-velocity shape factor.

double& OpenSim::Thelen2003Muscle::_damping [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_dampingProp [protected]

Passive damping included in the force-velocity relationship.

double& OpenSim::Thelen2003Muscle::_deactivationTimeConstant [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_deactivationTimeConstantProp [protected]

Deactivation time constant.

double& OpenSim::Thelen2003Muscle::_flen [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_flenProp [protected]

Maximum normalized lengthening force.

double& OpenSim::Thelen2003Muscle::_fmaxMuscleStrain [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_fmaxMuscleStrainProp [protected]

Passive muscle strain due to maximum isometric muscle force.

double& OpenSim::Thelen2003Muscle::_fmaxTendonStrain [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_fmaxTendonStrainProp [protected]

Tendon strain due to maximum isometric muscle force.

double& OpenSim::Thelen2003Muscle::_kShapeActive [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_kShapeActiveProp [protected]

Shape factor for Gaussian active muscle force-length relationship.

double& OpenSim::Thelen2003Muscle::_kShapePassive [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_kShapePassiveProp [protected]

Exponential shape factor for passive force-length relationship.

double& OpenSim::Thelen2003Muscle::_maxIsometricForce [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_maxIsometricForceProp [protected]

Maximum isometric force that the fibers can generate.

double& OpenSim::Thelen2003Muscle::_optimalFiberLength [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_optimalFiberLengthProp [protected]

Optimal length of the muscle fibers.

SimTK::CacheEntryIndex OpenSim::Thelen2003Muscle::_passiveForceIndex [protected]
double& OpenSim::Thelen2003Muscle::_pennationAngle [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_pennationAngleProp [protected]

Angle between tendon and fibers at optimal fiber length.

SimTK::CacheEntryIndex OpenSim::Thelen2003Muscle::_tendonForceIndex [protected]

indexes for Forces in various components

double& OpenSim::Thelen2003Muscle::_tendonSlackLength [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_tendonSlackLengthProp [protected]

Resting length of the tendon.

double& OpenSim::Thelen2003Muscle::_vmax [protected]
double& OpenSim::Thelen2003Muscle::_vmax0 [protected]
PropertyDbl OpenSim::Thelen2003Muscle::_vmax0Prop [protected]

Max contraction velocity at low activation.

PropertyDbl OpenSim::Thelen2003Muscle::_vmaxProp [protected]

Max contraction velocity full activation in fiber lengths per second.

const int Thelen2003Muscle::STATE_ACTIVATION = 0 [static, protected]
const int Thelen2003Muscle::STATE_FIBER_LENGTH = 1 [static, protected]
The documentation for this class was generated from the following files:
Generated on Wed Dec 16 15:03:39 2009 for OpenSim by  doxygen 1.6.1