OpenSim::Delp1990Muscle Class Reference

A class implementing a SIMM muscle. More...

#include <Delp1990Muscle.h>

Inheritance diagram for OpenSim::Delp1990Muscle:

List of all members.

Public Member Functions
	Delp1990Muscle ()
	Default constructor.
	Delp1990Muscle (const Delp1990Muscle &aMuscle)
	Copy constructor.
virtual	~Delp1990Muscle ()
	Destructor.
virtual Object *	copy () const
	Copy this muscle point and return a pointer to the copy.
Delp1990Muscle &	operator= (const Delp1990Muscle &aMuscle)
	Assignment operator.
virtual void	initStateCache (SimTK::State &s, SimTK::SubsystemIndex subsystemIndex, Model &model)
	allocate and initialize the SimTK state for this acuator.
virtual void	equilibrate (SimTK::State &state) const
void	copyData (const Delp1990Muscle &aMuscle)
	Copy data members from one Delp1990Muscle to another.
virtual void	copyPropertyValues (Actuator &aActuator)
	Copy the property values from another actuator, which may not be a Delp1990Muscle.
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	getMaxContractionVelocity () const
virtual double	getTimeScale () const
virtual double	getMass () const
virtual bool	setTimeScale (double aTimeScale)
	Set the scale factor for normalizing time.
virtual bool	setActivation1 (double aActivation1)
	Set the time constant of ramping up of muscle force.
virtual bool	setActivation2 (double aActivation2)
	Set the time constant of ramping up and 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	setMaxContractionVelocity (double aMaxContractionVelocity)
	Set the maximum contraction velocity of the fibers, in optimal fiber lengths per second.
virtual bool	setMass (double aMass)
	Set the mass of the muscle.
virtual double	getPennationAngle (const SimTK::State &) const
	Get the current pennation angle of the muscle fiber(s).
virtual double	getNormalizedFiberLength (const SimTK::State &) const
	Get the normalized length of the muscle fiber(s).
virtual double	getPassiveFiberForce (const SimTK::State &) const
	Get the passive force generated by the muscle fibers.
double	getStress (const SimTK::State &s) const
	Compute stress.
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 double	getFiberVelocity (const SimTK::State &s) const
virtual void	setFiberVelocity (SimTK::State &s, double fiberVelocity) const
virtual double	getFiberVelocityDeriv (const SimTK::State &s) const
virtual void	setFiberVelocityDeriv (const SimTK::State &s, double fiberVelocityDeriv) 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.
virtual double	computeIsometricForce (SimTK::State &s, double activation) const
	computeIsometricForce: this function finds the force in a muscle, 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	setup (Model &aModel)
	Perform some set up functions that happen after the object has been deserialized or copied.
virtual Function *	getActiveForceLengthCurve () const
	Get the active force-length curve.
virtual bool	setActiveForceLengthCurve (Function *aActiveForceLengthCurve)
	Set the active force-length curve.
virtual Function *	getPassiveForceLengthCurve () const
	Get the passive force-length curve.
virtual bool	setPassiveForceLengthCurve (Function *aPassiveForceLengthCurve)
	Set the passive force-length curve.
virtual Function *	getTendonForceLengthCurve () const
	Get the tendon force-length curve.
virtual bool	setTendonForceLengthCurve (Function *aTendonForceLengthCurve)
	Set the tendon force-length curve.
virtual Function *	getForceVelocityCurve () const
	Get the force-velocity curve.
virtual bool	setForceVelocityCurve (Function *aForceVelocityCurve)
	Set the force-velocity curve.
	OPENSIM_DECLARE_DERIVED (Delp1990Muscle, Actuator)
Protected Attributes
PropertyDbl	_timeScaleProp
	Scale factor for normalizing time.
double &	_timeScale
PropertyDbl	_activation1Prop
	Parameter used in time constant of ramping up of muscle force.
double &	_activation1
PropertyDbl	_activation2Prop
	Parameter used in time constant of ramping up and ramping down of muscle force.
double &	_activation2
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	_maxContractionVelocityProp
	Maximum contraction velocity of the fibers, in optimal fiberlengths per second.
double &	_maxContractionVelocity
PropertyDbl	_massProp
	Mass between the tendon and muscle fibers.
double &	_mass
PropertyObjPtr< Function >	_tendonForceLengthCurveProp
Function *&	_tendonForceLengthCurve
PropertyObjPtr< Function >	_activeForceLengthCurveProp
Function *&	_activeForceLengthCurve
PropertyObjPtr< Function >	_passiveForceLengthCurveProp
Function *&	_passiveForceLengthCurve
PropertyObjPtr< Function >	_forceVelocityCurveProp
Function *&	_forceVelocityCurve
SimTK::CacheEntryIndex	_tendonForceIndex
SimTK::CacheEntryIndex	_activeForceIndex
SimTK::CacheEntryIndex	_passiveForceIndex

---

Detailed Description

A class implementing a SIMM muscle.

This implementation is based on muscle model 2 from the Dynamics Pipeline, but is modified slightly so that when fiber_velocity = 0.0, this model calculates lengths and forces that match SIMM's isometric calculations.

Author:

Peter Loan

Version:

1.0

---

Constructor & Destructor Documentation

Delp1990Muscle::Delp1990Muscle

(

)

Default constructor.

Delp1990Muscle::Delp1990Muscle

(

const Delp1990Muscle &

aMuscle

)

Copy constructor.

Parameters:

aMuscle

Delp1990Muscle to be copied.

Delp1990Muscle::~Delp1990Muscle

(

)

[virtual]

Destructor.

---

Member Function Documentation

double Delp1990Muscle::computeActuation

(

const SimTK::State &

s

)

const [virtual]

Compute the actuation for the muscle.

This function assumes that computeDerivatives has already been called.

Reimplemented from OpenSim::Muscle.

void Delp1990Muscle::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 Delp1990Muscle::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 Delp1990Muscle::computeIsometricForce	(	SimTK::State &	s,
		double	aActivation
	)			const [virtual]

computeIsometricForce: this function finds the force in a muscle, 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, fiber length, active force, and passive force.

Parameters:

aActivation

Activation of the muscle.

Returns:

The isometric force in the muscle.

Implements OpenSim::Muscle.

void Delp1990Muscle::computeStateDerivatives

(

const SimTK::State &

s

)

[virtual]

Compute the derivatives of the muscle states.

Parameters:

rDYDT

the state derivatives are returned here.

Reimplemented from OpenSim::Actuator.

Object * Delp1990Muscle::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 Delp1990Muscle.

Implements OpenSim::Muscle.

void Delp1990Muscle::copyData

(

const Delp1990Muscle &

aMuscle

)

Copy data members from one Delp1990Muscle to another.

Parameters:

aMuscle

Delp1990Muscle to be copied.

Reimplemented from OpenSim::Muscle.

void Delp1990Muscle::copyPropertyValues

(

Actuator &

aActuator

)

[virtual]

Copy the property values from another actuator, which may not be a Delp1990Muscle.

Parameters:

aActuator

Actuator to copy property values from.

void Delp1990Muscle::equilibrate

(

SimTK::State &

state

)

const [virtual]

Reimplemented from OpenSim::Muscle.

virtual double OpenSim::Delp1990Muscle::getActivation

(

const SimTK::State &

s

)

const [inline, virtual]

Implements OpenSim::Muscle.

virtual double OpenSim::Delp1990Muscle::getActivationDeriv

(

const SimTK::State &

s

)

const [inline, virtual]

double Delp1990Muscle::getActiveForce

(

const SimTK::State &

s

)

const [virtual]

Function * Delp1990Muscle::getActiveForceLengthCurve

(

)

const [virtual]

Get the active force-length curve.

Returns:

Pointer to the active force-length curve (Function).

virtual double OpenSim::Delp1990Muscle::getFiberLength

(

const SimTK::State &

s

)

const [inline, virtual]

Implements OpenSim::Muscle.

virtual double OpenSim::Delp1990Muscle::getFiberLengthDeriv

(

const SimTK::State &

s

)

const [inline, virtual]

virtual double OpenSim::Delp1990Muscle::getFiberVelocity

(

const SimTK::State &

s

)

const [inline, virtual]

virtual double OpenSim::Delp1990Muscle::getFiberVelocityDeriv

(

const SimTK::State &

s

)

const [inline, virtual]

Function * Delp1990Muscle::getForceVelocityCurve

(

)

const [virtual]

Get the force-velocity curve.

Returns:

Pointer to the force-velocity curve (Function).

virtual double OpenSim::Delp1990Muscle::getMass

(

)

const [inline, virtual]

virtual double OpenSim::Delp1990Muscle::getMaxContractionVelocity

(

)

const [inline, virtual]

virtual double OpenSim::Delp1990Muscle::getMaxIsometricForce

(

)

const [inline, virtual]

getMaxIsometricForce needs to be overridden by derived classes to be usable

Reimplemented from OpenSim::Muscle.

double Delp1990Muscle::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::Delp1990Muscle::getOptimalFiberLength

(

)

const [inline, virtual]

double Delp1990Muscle::getPassiveFiberForce

(

const SimTK::State &

s

)

const [virtual]

Get the passive force generated by the muscle fibers.

Parameters:

Current

active force of the muscle fiber(s).

Implements OpenSim::Muscle.

double Delp1990Muscle::getPassiveForce

(

const SimTK::State &

s

)

const [virtual]

Function * Delp1990Muscle::getPassiveForceLengthCurve

(

)

const [virtual]

Get the passive force-length curve.

Returns:

Pointer to the passive force-length curve (Function).

double Delp1990Muscle::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::Delp1990Muscle::getPennationAngleAtOptimalFiberLength

(

)

const [inline, virtual]

Implements OpenSim::Muscle.

double Delp1990Muscle::getStress

(

const SimTK::State &

s

)

const [virtual]

Compute stress.

Reimplemented from OpenSim::Actuator.

double Delp1990Muscle::getTendonForce

(

const SimTK::State &

s

)

const [virtual]

Function * Delp1990Muscle::getTendonForceLengthCurve

(

)

const [virtual]

Get the tendon force-length curve.

Returns:

Pointer to the tendon force-length curve (Function).

virtual double OpenSim::Delp1990Muscle::getTendonSlackLength

(

)

const [inline, virtual]

virtual double OpenSim::Delp1990Muscle::getTimeScale

(

)

const [inline, virtual]

void Delp1990Muscle::initStateCache	(	SimTK::State &	s,
		SimTK::SubsystemIndex	subsystemIndex,
		Model &	model
	)			[virtual]

allocate and initialize the SimTK state for this acuator.

Reimplemented from OpenSim::Muscle.

OpenSim::Delp1990Muscle::OPENSIM_DECLARE_DERIVED	(	Delp1990Muscle	,
		Actuator
	)

Reimplemented from OpenSim::CustomActuator.

Delp1990Muscle & Delp1990Muscle::operator=

(

const Delp1990Muscle &

aMuscle

)

Assignment operator.

Returns:

Reference to this object.

Reimplemented from OpenSim::Muscle.

void Delp1990Muscle::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 Delp1990Muscle::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::Delp1990Muscle::setActivation	(	SimTK::State &	s,
		double	activation
	)			const [inline, virtual]

Implements OpenSim::Muscle.

bool Delp1990Muscle::setActivation1

(

double

aActivation1

)

[virtual]

Set the time constant of ramping up of muscle force.

Parameters:

aActivation1

The time constant of ramping up of muscle force.

Returns:

Whether the time constant was successfully changed.

bool Delp1990Muscle::setActivation2

(

double

aActivation2

)

[virtual]

Set the time constant of ramping up and ramping down of muscle force.

Parameters:

aActivation1

The time constant of ramping up and ramping down of muscle force.

Returns:

Whether the time constant was successfully changed.

virtual void OpenSim::Delp1990Muscle::setActivationDeriv	(	const SimTK::State &	s,
		double	activationDeriv
	)			const [inline, virtual]

void Delp1990Muscle::setActiveForce	(	const SimTK::State &	s,
		double	aForce
	)			const [virtual]

bool Delp1990Muscle::setActiveForceLengthCurve

(

Function *

aActiveForceLengthCurve

)

[virtual]

Set the active force-length curve.

Parameters:

aActiveForceLengthCurve

Pointer to an active force-length curve (Function).

Returns:

Whether active force-length curve was successfully changed.

virtual void OpenSim::Delp1990Muscle::setFiberLength	(	SimTK::State &	s,
		double	fiberLength
	)			const [inline, virtual]

Implements OpenSim::Muscle.

virtual void OpenSim::Delp1990Muscle::setFiberLengthDeriv	(	const SimTK::State &	s,
		double	fiberLengthDeriv
	)			const [inline, virtual]

virtual void OpenSim::Delp1990Muscle::setFiberVelocity	(	SimTK::State &	s,
		double	fiberVelocity
	)			const [inline, virtual]

virtual void OpenSim::Delp1990Muscle::setFiberVelocityDeriv	(	const SimTK::State &	s,
		double	fiberVelocityDeriv
	)			const [inline, virtual]

bool Delp1990Muscle::setForceVelocityCurve

(

Function *

aForceVelocityCurve

)

[virtual]

Set the force-velocity curve.

Parameters:

aForceVelocityCurve

Pointer to a force-velocity curve (Function).

Returns:

Whether force-velocity curve was successfully changed.

bool Delp1990Muscle::setMass

(

double

aMass

)

[virtual]

Set the mass of the muscle.

Parameters:

aMass

The mass of the muscle.

Returns:

Whether the mass was successfully changed.

bool Delp1990Muscle::setMaxContractionVelocity

(

double

aMaxContractionVelocity

)

[virtual]

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

Parameters:

aMaxContractionVelocity

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

Returns:

Whether the maximum contraction velocity was successfully changed.

bool Delp1990Muscle::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 Delp1990Muscle::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 Delp1990Muscle::setPassiveForce	(	const SimTK::State &	s,
		double	aForce
	)			const [virtual]

bool Delp1990Muscle::setPassiveForceLengthCurve

(

Function *

aPassiveForceLengthCurve

)

[virtual]

Set the passive force-length curve.

Parameters:

aPassiveForceLengthCurve

Pointer to a passive force-length curve (Function).

Returns:

Whether passive force-length curve was successfully changed.

bool Delp1990Muscle::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 Delp1990Muscle::setTendonForce	(	const SimTK::State &	s,
		double	aForce
	)			const [virtual]

bool Delp1990Muscle::setTendonForceLengthCurve

(

Function *

aTendonForceLengthCurve

)

[virtual]

Set the tendon force-length curve.

Parameters:

aTendonForceLengthCurve

Pointer to a tendon force-length curve (Function).

Returns:

Whether tendon force-length curve was successfully changed.

bool Delp1990Muscle::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.

bool Delp1990Muscle::setTimeScale

(

double

aTimeScale

)

[virtual]

Set the scale factor for normalizing time.

Parameters:

aTimeScale

The scale factor for normalizing time.

Returns:

Whether the scale factor was successfully changed.

void Delp1990Muscle::setup

(

Model &

aModel

)

[virtual]

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

Parameters:

aModel

model containing this Delp1990Muscle.

Reimplemented from OpenSim::Muscle.

---

Member Data Documentation

double& OpenSim::Delp1990Muscle::_activation1 [protected]

PropertyDbl OpenSim::Delp1990Muscle::_activation1Prop [protected]

Parameter used in time constant of ramping up of muscle force.

double& OpenSim::Delp1990Muscle::_activation2 [protected]

PropertyDbl OpenSim::Delp1990Muscle::_activation2Prop [protected]

Parameter used in time constant of ramping up and ramping down of muscle force.

SimTK::CacheEntryIndex OpenSim::Delp1990Muscle::_activeForceIndex [protected]

Function*& OpenSim::Delp1990Muscle::_activeForceLengthCurve [protected]

PropertyObjPtr<Function> OpenSim::Delp1990Muscle::_activeForceLengthCurveProp [protected]

Function*& OpenSim::Delp1990Muscle::_forceVelocityCurve [protected]

PropertyObjPtr<Function> OpenSim::Delp1990Muscle::_forceVelocityCurveProp [protected]

double& OpenSim::Delp1990Muscle::_mass [protected]

PropertyDbl OpenSim::Delp1990Muscle::_massProp [protected]

Mass between the tendon and muscle fibers.

double& OpenSim::Delp1990Muscle::_maxContractionVelocity [protected]

PropertyDbl OpenSim::Delp1990Muscle::_maxContractionVelocityProp [protected]

Maximum contraction velocity of the fibers, in optimal fiberlengths per second.

double& OpenSim::Delp1990Muscle::_maxIsometricForce [protected]

PropertyDbl OpenSim::Delp1990Muscle::_maxIsometricForceProp [protected]

Maximum isometric force that the fibers can generate.

double& OpenSim::Delp1990Muscle::_optimalFiberLength [protected]

PropertyDbl OpenSim::Delp1990Muscle::_optimalFiberLengthProp [protected]

Optimal length of the muscle fibers.

SimTK::CacheEntryIndex OpenSim::Delp1990Muscle::_passiveForceIndex [protected]

Function*& OpenSim::Delp1990Muscle::_passiveForceLengthCurve [protected]

PropertyObjPtr<Function> OpenSim::Delp1990Muscle::_passiveForceLengthCurveProp [protected]

double& OpenSim::Delp1990Muscle::_pennationAngle [protected]

PropertyDbl OpenSim::Delp1990Muscle::_pennationAngleProp [protected]

Angle between tendon and fibers at optimal fiber length.

SimTK::CacheEntryIndex OpenSim::Delp1990Muscle::_tendonForceIndex [protected]

Function*& OpenSim::Delp1990Muscle::_tendonForceLengthCurve [protected]

PropertyObjPtr<Function> OpenSim::Delp1990Muscle::_tendonForceLengthCurveProp [protected]

double& OpenSim::Delp1990Muscle::_tendonSlackLength [protected]

PropertyDbl OpenSim::Delp1990Muscle::_tendonSlackLengthProp [protected]

Resting length of the tendon.

double& OpenSim::Delp1990Muscle::_timeScale [protected]

PropertyDbl OpenSim::Delp1990Muscle::_timeScaleProp [protected]

Scale factor for normalizing time.

---

The documentation for this class was generated from the following files:

• OpenSim/Actuators/Delp1990Muscle.h
• OpenSim/Actuators/Delp1990Muscle.cpp