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Millard2012AccelerationMuscle.cpp
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Millard2012AccelerationMuscle.cpp
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/* -------------------------------------------------------------------------- *
* OpenSim: Millard2012AccelerationMuscle.cpp *
* -------------------------------------------------------------------------- *
* The OpenSim API is a toolkit for musculoskeletal modeling and simulation. *
* See http://opensim.stanford.edu and the NOTICE file for more information. *
* OpenSim is developed at Stanford University and supported by the US *
* National Institutes of Health (U54 GM072970, R24 HD065690) and by DARPA *
* through the Warrior Web program. *
* *
* Copyright (c) 2005-2012 Stanford University and the Authors *
* Author(s): Matthew Millard *
* *
* Licensed under the Apache License, Version 2.0 (the "License"); you may *
* not use this file except in compliance with the License. You may obtain a *
* copy of the License at http://www.apache.org/licenses/LICENSE-2.0. *
* *
* Unless required by applicable law or agreed to in writing, software *
* distributed under the License is distributed on an "AS IS" BASIS, *
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
* See the License for the specific language governing permissions and *
* limitations under the License. *
* -------------------------------------------------------------------------- */
//=============================================================================
// INCLUDES
//=============================================================================
#include "Millard2012AccelerationMuscle.h"
#include <OpenSim/Common/SimmMacros.h>
#include <OpenSim/Common/DebugUtilities.h>
#include <OpenSim/Simulation/Model/Model.h>
#include <Simbody.h>
#include <iostream>
//=============================================================================
// STATICS
//=============================================================================
using namespace std;
using namespace OpenSim;
using namespace SimTK;
///@cond
const string Millard2012AccelerationMuscle::
STATE_ACTIVATION_NAME = "activation";
const string Millard2012AccelerationMuscle::
STATE_FIBER_LENGTH_NAME = "fiber_length";
const string Millard2012AccelerationMuscle::
STATE_FIBER_VELOCITY_NAME = "fiber_velocity";
///@endcond
const static int MLIfse = 0;
const static int MLIfk = 1;
const static int MLIfcphi = 2;
const static int MLIfkPE = 3;
const static int MLIfcphiPE = 4;
const static int MVIdlceAT = 0;
const static int MDIFiberAcceleration = 0;
//=============================================================================
// PROPERTY MANAGEMENT
//=============================================================================
void Millard2012AccelerationMuscle::setNull()
{
setAuthors("Matthew Millard");
}
void Millard2012AccelerationMuscle::constructProperties()
{
constructProperty_default_activation(0.0); //getMinActivation()
constructProperty_default_fiber_length(getOptimalFiberLength());
constructProperty_default_fiber_velocity(0.0);
MuscleFirstOrderActivationDynamicModel defaultActMdl =
MuscleFirstOrderActivationDynamicModel();
double tauAct = defaultActMdl.get_activation_time_constant();
double tauDact= defaultActMdl.get_deactivation_time_constant();
//Ensure the minimum allowed activation is 0.
constructProperty_MuscleFirstOrderActivationDynamicModel(
MuscleFirstOrderActivationDynamicModel(tauAct,tauDact,0,getName()));
ActiveForceLengthCurve defaultFal = ActiveForceLengthCurve();
double lceMin = defaultFal.getMinActiveFiberLength();
double lceTrans= defaultFal.getTransitionFiberLength();
double lceMax = defaultFal.getMaxActiveFiberLength();
double slope = defaultFal.getShallowAscendingSlope();
double minFal = 0; //
//Ensure the Active Force Length Curve can go to 0
constructProperty_ActiveForceLengthCurve(
ActiveForceLengthCurve(lceMin,lceTrans,lceMax,slope,minFal));
ForceVelocityCurve defaultFv = ForceVelocityCurve();
double concSlopeAtVmax = 0;
double concSlopeNearVmax = defaultFv.getConcentricSlopeNearVmax();
double isoSlope = defaultFv.getIsometricSlope();
double eccSlopeNearVmax = defaultFv.getEccentricSlopeNearVmax();
double eccSlopeAtVmax = 0;
double maxFv = defaultFv.getMaxEccentricVelocityForceMultiplier();
double concCurviness= defaultFv.getConcentricCurviness();
double eccCurviness = defaultFv.getEccentricCurviness();
//Ensure the force velocity curve has asymptotes
constructProperty_ForceVelocityCurve(
ForceVelocityCurve( concSlopeAtVmax,
concSlopeNearVmax,
isoSlope,
eccSlopeAtVmax,
eccSlopeNearVmax,
maxFv,
concCurviness,
eccCurviness) );
constructProperty_FiberForceLengthCurve(
FiberForceLengthCurve());
constructProperty_TendonForceLengthCurve(
TendonForceLengthCurve());
constructProperty_FiberCompressiveForceLengthCurve(
FiberCompressiveForceLengthCurve());
constructProperty_FiberCompressiveForceCosPennationCurve(
FiberCompressiveForceCosPennationCurve());
//Nonlinear damping coefficients
constructProperty_tendon_force_length_damping(1e-1);
constructProperty_fiber_compressive_force_length_damping(1.0);
constructProperty_fiber_force_length_damping(1e-2);
constructProperty_fiber_compressive_force_cos_pennation_damping(1.0);
//Linear fiber damping as in Schutte's model
constructProperty_fiber_damping(1e-2);
//Mass property
constructProperty_mass(0.1);
}
void Millard2012AccelerationMuscle::buildMuscle()
{
double optFibLen = getOptimalFiberLength();
double optPenAng = getPennationAngleAtOptimalFiberLength();
std::string caller = getName();
caller.append(".buildMuscle()");
m_penMdl = MuscleFixedWidthPennationModel( optFibLen,
optPenAng,
SimTK::Pi/2.0);
std::string aName = getName();
std::string tmp = aName;
tmp.append("_MuscleFirstOrderActivationDynamicModel");
MuscleFirstOrderActivationDynamicModel& actMdl = upd_MuscleFirstOrderActivationDynamicModel();
actMdl.setName(tmp);
tmp = aName;
tmp.append("_ActiveForceLengthCurve");
ActiveForceLengthCurve& falCurve = upd_ActiveForceLengthCurve();
falCurve.setName(tmp);
tmp = aName;
tmp.append("_ForceVelocityCurve");
ForceVelocityCurve& fvCurve = upd_ForceVelocityCurve();
fvCurve.setName(tmp);
tmp = aName;
tmp.append("_FiberForceLengthCurve");
FiberForceLengthCurve& fpeCurve = upd_FiberForceLengthCurve();
fpeCurve.setName(tmp);
tmp = aName;
tmp.append("_TendonForceLengthCurve");
TendonForceLengthCurve& fseCurve = upd_TendonForceLengthCurve();
fseCurve.setName(tmp);
tmp = aName;
tmp.append("_FiberCompressiveForceLengthCurve");
FiberCompressiveForceLengthCurve& fkCurve
= upd_FiberCompressiveForceLengthCurve();
fkCurve.setName(tmp);
tmp = aName;
tmp.append("_FiberCompressiveForceCosPennationCurve");
FiberCompressiveForceCosPennationCurve& fcphi =
upd_FiberCompressiveForceCosPennationCurve();
fcphi.setName(tmp);
//Ensure all sub objects are up to date with properties;
actMdl.finalizeFromProperties(); //TODO: Remove this once the activation
//model has been made into a property.
// TODO: Remove this once MuscleFixedWidthPennationModel has been made into
// a property.
m_penMdl.finalizeFromProperties();
falCurve.ensureCurveUpToDate();
fvCurve.ensureCurveUpToDate();
fpeCurve.ensureCurveUpToDate();
fseCurve.ensureCurveUpToDate();
fkCurve.ensureCurveUpToDate();
fcphi.ensureCurveUpToDate();
setObjectIsUpToDateWithProperties();
}
void Millard2012AccelerationMuscle::extendFinalizeFromProperties()
{
Super::extendFinalizeFromProperties();
buildMuscle();
}
//=============================================================================
// CONSTRUCTOR(S) AND DESTRUCTOR
//=============================================================================
Millard2012AccelerationMuscle::Millard2012AccelerationMuscle()
{
setNull();
constructInfrastructure();
// TODO: Remove this once MuscleFirstOrderActivationDynamicModel and
// MuscleFixedWidthPennationModel have been made into properties.
finalizeFromProperties();
}
Millard2012AccelerationMuscle::
Millard2012AccelerationMuscle(const std::string &aName, double aMaxIsometricForce,
double aOptimalFiberLength,double aTendonSlackLength,
double aPennationAngle)
{
setNull();
constructInfrastructure();
setName(aName);
setMaxIsometricForce(aMaxIsometricForce);
setOptimalFiberLength(aOptimalFiberLength);
setTendonSlackLength(aTendonSlackLength);
setPennationAngleAtOptimalFiberLength(aPennationAngle);
// TODO: Remove this once MuscleFirstOrderActivationDynamicModel and
// MuscleFixedWidthPennationModel have been made into properties.
finalizeFromProperties();
}
//=============================================================================
// Model Component Interface
//=============================================================================
void Millard2012AccelerationMuscle::
extendAddToSystem(SimTK::MultibodySystem& system) const
{
Super::extendAddToSystem(system);
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
addStateVariable(STATE_ACTIVATION_NAME);
addStateVariable(STATE_FIBER_LENGTH_NAME);
addStateVariable(STATE_FIBER_VELOCITY_NAME);
}
void Millard2012AccelerationMuscle::extendInitStateFromProperties(SimTK::State& s) const
{
Super::extendInitStateFromProperties(s);
setActivation(s, getDefaultActivation());
setFiberLength(s, getDefaultFiberLength());
setFiberVelocity(s,getDefaultFiberVelocity());
}
void Millard2012AccelerationMuscle::
extendSetPropertiesFromState(const SimTK::State& s)
{
Super::extendSetPropertiesFromState(s);
setDefaultActivation(getStateVariableValue(s,STATE_ACTIVATION_NAME));
setDefaultFiberLength(getStateVariableValue(s,STATE_FIBER_LENGTH_NAME));
setDefaultFiberVelocity(getStateVariableValue(s,STATE_FIBER_VELOCITY_NAME));
}
void Millard2012AccelerationMuscle::
computeStateVariableDerivatives(const SimTK::State& s) const
{
double adot=0, ldot=0, vdot=0;
if(!isDisabled(s)){
adot = getActivationRate(s);
ldot = getFiberVelocity(s);
vdot = getFiberAcceleration(s);
}
setStateVariableDerivativeValue(s, STATE_ACTIVATION_NAME, adot);
setStateVariableDerivativeValue(s, STATE_FIBER_LENGTH_NAME, ldot);
setStateVariableDerivativeValue(s, STATE_FIBER_VELOCITY_NAME, vdot);
}
//=============================================================================
// STATE RELATED GET FUNCTIONS
//=============================================================================
double Millard2012AccelerationMuscle::getDefaultActivation() const
{
return get_default_activation();
}
double Millard2012AccelerationMuscle::getDefaultFiberLength() const
{
return get_default_fiber_length();
}
double Millard2012AccelerationMuscle::getDefaultFiberVelocity() const
{
return get_default_fiber_velocity();
}
double Millard2012AccelerationMuscle::
getActivationRate(const SimTK::State& s) const
{
return calcActivationRate(s);
}
double Millard2012AccelerationMuscle::
getFiberVelocity(const SimTK::State& s) const
{
FiberVelocityInfo fvi = getFiberVelocityInfo(s);
return fvi.fiberVelocity;
}
double Millard2012AccelerationMuscle::
getFiberAcceleration(const SimTK::State& s) const
{
MuscleDynamicsInfo fdi = getMuscleDynamicsInfo(s);
return fdi.userDefinedDynamicsExtras[MDIFiberAcceleration];
}
//=============================================================================
// STATE RELATED SET FUNCTIONS
//=============================================================================
void Millard2012AccelerationMuscle::setDefaultActivation(double activation)
{
set_default_activation(activation);
}
void Millard2012AccelerationMuscle::setDefaultFiberLength(double fiberLength)
{
set_default_fiber_length(fiberLength);
}
void Millard2012AccelerationMuscle::
setDefaultFiberVelocity(double fiberVelocity)
{
set_default_fiber_velocity(fiberVelocity);
}
void Millard2012AccelerationMuscle::
setActivation(SimTK::State& s, double activation) const
{
setStateVariableValue(s, STATE_ACTIVATION_NAME, activation);
markCacheVariableInvalid(s,"dynamicsInfo");
}
void Millard2012AccelerationMuscle::
setFiberLength(SimTK::State& s, double fiberLength) const
{
setStateVariableValue(s, STATE_FIBER_LENGTH_NAME, fiberLength);
markCacheVariableInvalid(s,"lengthInfo");
markCacheVariableInvalid(s,"velInfo");
markCacheVariableInvalid(s,"dynamicsInfo");
}
void Millard2012AccelerationMuscle::
setFiberVelocity(SimTK::State& s, double fiberVelocity) const
{
setStateVariableValue(s, STATE_FIBER_VELOCITY_NAME, fiberVelocity);
markCacheVariableInvalid(s,"velInfo");
markCacheVariableInvalid(s,"dynamicsInfo");
}
//=============================================================================
// GET
//=============================================================================
double Millard2012AccelerationMuscle::
getFiberCompressiveForceLengthMultiplier(SimTK::State& s) const
{
const MuscleLengthInfo& mli = getMuscleLengthInfo(s);
return mli.userDefinedLengthExtras[MLIfk];
}
double Millard2012AccelerationMuscle::
getFiberCompressiveForceCosPennationMultiplier(SimTK::State& s) const
{
const MuscleLengthInfo& mli = getMuscleLengthInfo(s);
return mli.userDefinedLengthExtras[MLIfcphi];
}
double Millard2012AccelerationMuscle::
getTendonForceMultiplier(SimTK::State& s) const
{
const MuscleLengthInfo& mli = getMuscleLengthInfo(s);
return mli.userDefinedLengthExtras[MLIfse];
}
const MuscleFirstOrderActivationDynamicModel& Millard2012AccelerationMuscle::
getActivationModel() const
{
return get_MuscleFirstOrderActivationDynamicModel();
}
const MuscleFixedWidthPennationModel& Millard2012AccelerationMuscle::
getPennationModel() const
{
return m_penMdl;
}
const ActiveForceLengthCurve& Millard2012AccelerationMuscle::
getActiveForceLengthCurve() const
{
return get_ActiveForceLengthCurve();
}
const ForceVelocityCurve& Millard2012AccelerationMuscle::
getForceVelocityCurve() const
{
return get_ForceVelocityCurve();
}
const FiberForceLengthCurve& Millard2012AccelerationMuscle::
getFiberForceLengthCurve() const
{
return get_FiberForceLengthCurve();
}
const TendonForceLengthCurve& Millard2012AccelerationMuscle::
getTendonForceLengthCurve() const
{
return get_TendonForceLengthCurve();
}
const FiberCompressiveForceLengthCurve& Millard2012AccelerationMuscle::
getFiberCompressiveForceLengthCurve() const
{
return get_FiberCompressiveForceLengthCurve();
}
const FiberCompressiveForceCosPennationCurve& Millard2012AccelerationMuscle::
getFiberCompressiveForceCosPennationCurve() const
{
return get_FiberCompressiveForceCosPennationCurve();
}
double Millard2012AccelerationMuscle::
getFiberStiffnessAlongTendon(const SimTK::State& s) const
{
const MuscleDynamicsInfo& mdi = getMuscleDynamicsInfo(s);
return mdi.fiberStiffnessAlongTendon;
}
double Millard2012AccelerationMuscle::getMass() const
{
return get_mass();
}
//=============================================================================
// SET
//=============================================================================
void Millard2012AccelerationMuscle::setActivationModel(
MuscleFirstOrderActivationDynamicModel& aActivationMdl)
{
set_MuscleFirstOrderActivationDynamicModel(aActivationMdl);
}
void Millard2012AccelerationMuscle::setActiveForceLengthCurve(
ActiveForceLengthCurve& aActiveForceLengthCurve)
{
set_ActiveForceLengthCurve(aActiveForceLengthCurve);
}
void Millard2012AccelerationMuscle::setForceVelocityCurve(
ForceVelocityCurve& aForceVelocityCurve)
{
set_ForceVelocityCurve(aForceVelocityCurve);
}
void Millard2012AccelerationMuscle::setFiberForceLengthCurve(
FiberForceLengthCurve& aFiberForceLengthCurve)
{
set_FiberForceLengthCurve(aFiberForceLengthCurve);
}
void Millard2012AccelerationMuscle::setTendonForceLengthCurve(
TendonForceLengthCurve& aTendonForceLengthCurve)
{
set_TendonForceLengthCurve(aTendonForceLengthCurve);
}
void Millard2012AccelerationMuscle::setFiberCompressiveForceLengthCurve(
FiberCompressiveForceLengthCurve& aFiberCompressiveForceLengthCurve)
{
set_FiberCompressiveForceLengthCurve(
aFiberCompressiveForceLengthCurve);
}
void Millard2012AccelerationMuscle::setFiberCompressiveForceCosPennationCurve(
FiberCompressiveForceCosPennationCurve&
aFiberCompressiveForceCosPennationCurve)
{
set_FiberCompressiveForceCosPennationCurve(
aFiberCompressiveForceCosPennationCurve);
}
void Millard2012AccelerationMuscle::setMass(double mass)
{
SimTK_ERRCHK1_ALWAYS(mass >= 1e-3,
"Millard2012AccelerationMuscle::setMass",
"%s: The mass is set too small!",getName().c_str());
set_mass(mass);
}
//==============================================================================
// Protected Useful Functions
//==============================================================================
void Millard2012AccelerationMuscle::
postScale(const SimTK::State& s, const ScaleSet& aScaleSet)
{
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
GeometryPath& path = upd_GeometryPath();
path.postScale(s, aScaleSet);
if (path.getPreScaleLength(s) > 0.0)
{
double scaleFactor = getLength(s) / path.getPreScaleLength(s);
upd_optimal_fiber_length() *= scaleFactor;
upd_tendon_slack_length() *= scaleFactor;
path.setPreScaleLength(s, 0.0) ;
}
}
//==============================================================================
// XXXXXXXXXXXXXXXXXXXX START OF TO BE DEPRECATED XXXXXXXXXXXXXXXXXXXXXXXXXXX
//==============================================================================
double Millard2012AccelerationMuscle::
calcInextensibleTendonActiveFiberForce(SimTK::State& s,
double aActivation) const
{
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
string caller = getName();
caller.append( "Millard2012AccelerationMuscle::"
"calcInextensibleTendonActiveFiberForce");
double inextensibleTendonActiveFiberForce = 0;
double muscleLength = getLength(s);
double muscleVelocity = getLengtheningSpeed(s);
double tendonSlackLength = getTendonSlackLength();
double tendonVelocity = 0.0; //Inextensible tendon;
double fiberLength = m_penMdl.calcFiberLength(muscleLength,
tendonSlackLength);
if(fiberLength > m_penMdl.getMinimumFiberLength()){
double phi = m_penMdl.calcPennationAngle(fiberLength);
double fiberVelocity = m_penMdl.calcFiberVelocity(cos(phi),
muscleVelocity,tendonVelocity);
inextensibleTendonActiveFiberForce =
calcActiveFiberForceAlongTendon( aActivation,
fiberLength,
fiberVelocity);
}
return inextensibleTendonActiveFiberForce;
}
double Millard2012AccelerationMuscle::
calcActiveFiberForceAlongTendon(double activation,
double fiberLength,
double fiberVelocity) const
{
string caller = getName();
caller.append( "::MillardAccelerationMuscle::"
"calcActiveFiberForceAlongTendon");
double activeFiberForce = 0;
double clampedFiberLength = m_penMdl.clampFiberLength(fiberLength);
//If the fiber is in a legal range, compute the force its generating
if(fiberLength > m_penMdl.getMinimumFiberLength()){
//Clamp activation to a legal range
MuscleFirstOrderActivationDynamicModel actMdl
= get_MuscleFirstOrderActivationDynamicModel();
double clampedActivation = actMdl.clampActivation(activation);
//Normalize fiber length and velocity
double normFiberLength = clampedFiberLength/getOptimalFiberLength();
double normFiberVelocity = fiberVelocity /
(getOptimalFiberLength() * getMaxContractionVelocity());
//Get the necessary curves
const ActiveForceLengthCurve& falCurve
= getProperty_ActiveForceLengthCurve().getValue();
const ForceVelocityCurve& fvCurve
= getProperty_ForceVelocityCurve().getValue();
//Evaluate the force active length and force velocity multipliers
double fal = falCurve.calcValue(normFiberLength);
double fv = fvCurve.calcValue(normFiberVelocity);
double fiso = getMaxIsometricForce();
//Evaluate the pennation angle
double phi = m_penMdl.calcPennationAngle(fiberLength);
//Compute the active fiber force
activeFiberForce = fiso * clampedActivation * fal * fv * cos(phi);
}
//Compute the active fiber force
return activeFiberForce;
}
//==============================================================================
// XXXXXXXXXXXXXXXXXXXX END OF TO BE DEPRECATED XXXXXXXXXXXXXXXXXXXXXXXXXXX
//==============================================================================
//==============================================================================
// Muscle.h Interface
//==============================================================================
double Millard2012AccelerationMuscle::
computeActuation(const SimTK::State& s) const
{
//ensureMuscleUpToDate();
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
const MuscleDynamicsInfo& mdi = getMuscleDynamicsInfo(s);
setActuation(s, mdi.tendonForce);
return( mdi.tendonForce );
}
void Millard2012AccelerationMuscle::
computeInitialFiberEquilibrium(SimTK::State& s) const
{
try{
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
//Initial fiber length, fiber velocity, activation from input State s
_model->getMultibodySystem().realize(s, SimTK::Stage::Velocity);
//Compute an initial muscle state that develops the desired force and
//shares the muscle stretch between the muscle fiber and the tendon
//according to their relative stiffness.
double activation = getActivation(s);
//Tolerance, in Newtons, of the desired equilibrium
double tol = 1e-8*getMaxIsometricForce(); //Should this be user settable?
if(tol < SimTK::SignificantReal*10){
tol = SimTK::SignificantReal*10;
}
int maxIter = 500; //Should this be user settable?
double newtonStepFraction = 0.75;
SimTK::Vector soln = initMuscleState( s,
activation,
tol,
maxIter,
newtonStepFraction);
int flag_status = (int)soln[0];
double solnErr = soln[1];
int iterations = (int)soln[2];
double fiberLength = soln[3];
double fiberVelocity = soln[4];
double passiveForce = soln[5];
double tendonForce = soln[6];
switch(flag_status){
case 0: //converged, all is normal
{
setActuation(s, tendonForce);
setFiberLength(s,fiberLength);
setFiberVelocity(s,fiberVelocity);
}break;
case 1: //lower fiber length bound hit
{
setActuation(s, tendonForce);
setFiberLength(s,fiberLength);
setFiberVelocity(s,fiberVelocity);
std::string muscleName = getName();
printf( "\n\nMillard2012AccelerationMuscle Initialization Message:"
" %s is at its minimum length of %f",
muscleName.c_str(), m_penMdl.getMinimumFiberLength());
}break;
case 2: //Maximum number of iterations exceeded.
{
setActuation(s, 0.0);
setFiberLength(s, get_optimal_fiber_length());
setFiberVelocity(s,0.0);
std::string muscleName = getName();
std::string fcnName = "\n\nWARNING: Millard2012AccelerationMuscle::"
"computeInitialFiberEquilibrium(SimTK::State& s)";
char msgBuffer[1000];
int n = sprintf(msgBuffer,
"WARNING: No suitable initial conditions found for\n"
" %s: \n"
" by %s \n"
"Continuing with an initial fiber force, "
"length and velocity of 0, %f and 0\n"
" Here is a report from the routine:\n \n"
" Solution Error : %f > tol (%f) \n"
" Newton Iterations : %d of max. iterations (%d)\n"
" Check that the initial activation is valid,"
" and that the whole \n"
" length doesn't produce a pennation"
" angle of 90 degrees, nor a fiber\n"
" length less than 0:\n"
" Activation : %f \n"
" Whole muscle length : %f \n\n",
muscleName.c_str(),
fcnName.c_str(),
get_optimal_fiber_length(),
abs(solnErr),
tol,
iterations,
maxIter,
activation,
fiberLength);
cerr << msgBuffer << endl;
}break;
default:
std::string muscleName = getName();
printf(
"\n\nWARNING: Millard2012EquilibriumMuscle Initialization:"
" %s invalid error flag, setting tendon force to 0.0, "
"the fiber length to the optimal fiber length, "
"and a fiber velocity equal to 0.0 ",
muscleName.c_str());
setActuation(s, 0.0);
setFiberLength(s, get_optimal_fiber_length());
setFiberVelocity(s,0.0);
}
}catch (const std::exception& e) {
//If the initialization routine fails in some unexpected way, tell
//the user and continue with some valid initial conditions
cerr << "\n\nWARNING: Millard2012AccelerationMuscle initialization"
" exception caught:" << endl;
cerr << e.what() << endl;
cerr << " Continuing with initial tendon force of 0 " << endl;
cerr << " and a fiber length equal to the optimal fiber length,"
<< endl;
cerr << " and a fiber length velocity equal to 0 ..."
<< endl;
setActuation(s, 0);
setFiberLength(s,getOptimalFiberLength());
setFiberVelocity(s,0.0);
}
}
void Millard2012AccelerationMuscle::
calcMuscleLengthInfo(const SimTK::State& s, MuscleLengthInfo& mli) const
{
//ensureMuscleUpToDate();
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
double simTime = s.getTime(); //for debugging purposes
try{
//Get whole muscle properties
double maxIsoForce = getMaxIsometricForce();
double optFiberLength = getOptimalFiberLength();
double mclLength = getLength(s);
double tendonSlackLen = getTendonSlackLength();
std::string caller = getName();
caller.append(".calcMuscleLengthInfo");
//Get muscle model specific properties
const TendonForceLengthCurve& fseCurve = get_TendonForceLengthCurve();
const FiberForceLengthCurve& fpeCurve = get_FiberForceLengthCurve();
const ActiveForceLengthCurve& falCurve = get_ActiveForceLengthCurve();
const FiberCompressiveForceLengthCurve& fkCurve
= get_FiberCompressiveForceLengthCurve();
const FiberCompressiveForceCosPennationCurve& fcphiCurve
= get_FiberCompressiveForceCosPennationCurve();
//Populate the output struct
mli.fiberLength = getStateVariableValue(s, STATE_FIBER_LENGTH_NAME);
mli.normFiberLength = mli.fiberLength/optFiberLength;
mli.pennationAngle = m_penMdl.calcPennationAngle(mli.fiberLength);
mli.cosPennationAngle = cos(mli.pennationAngle);
mli.sinPennationAngle = sin(mli.pennationAngle);
mli.fiberLengthAlongTendon = mli.fiberLength*mli.cosPennationAngle;
mli.tendonLength = m_penMdl.calcTendonLength(mli.cosPennationAngle,
mli.fiberLength,mclLength);
mli.normTendonLength = mli.tendonLength / tendonSlackLen;
mli.tendonStrain = mli.normTendonLength - 1.0;
mli.fiberPassiveForceLengthMultiplier=
fpeCurve.calcValue(mli.normFiberLength);
mli.fiberActiveForceLengthMultiplier =
falCurve.calcValue(mli.normFiberLength);
double tendonForceLengthMultiplier=fseCurve.calcValue(mli.normTendonLength);
//Put in the additional length related terms that are specific to this
//particular muscle model.
mli.userDefinedLengthExtras.resize(5);
mli.userDefinedLengthExtras[MLIfse] = tendonForceLengthMultiplier;
mli.userDefinedLengthExtras[MLIfk] = fkCurve.calcValue(
mli.normFiberLength);
mli.userDefinedLengthExtras[MLIfcphi] = fcphiCurve.calcValue(
mli.cosPennationAngle);
}catch(const std::exception &x){
std::string msg = "Exception caught in Millard2012AccelerationMuscle::"
"calcMuscleLengthInfo\n"
"of " + getName() + "\n"
+ x.what();
throw OpenSim::Exception(msg);
}
}
void Millard2012AccelerationMuscle::calcMusclePotentialEnergyInfo(const SimTK::State& s,
MusclePotentialEnergyInfo& mpei) const
{
try {
//Get whole muscle properties
double maxIsoForce = getMaxIsometricForce();
double optFiberLength = getOptimalFiberLength();
double mclLength = getLength(s);
double tendonSlackLen = getTendonSlackLength();
// Get the quantities that we've already computed.
const MuscleLengthInfo &mli = getMuscleLengthInfo(s);
//Get muscle model specific properties
const TendonForceLengthCurve& fseCurve = get_TendonForceLengthCurve();
const FiberForceLengthCurve& fpeCurve = get_FiberForceLengthCurve();
const ActiveForceLengthCurve& falCurve = get_ActiveForceLengthCurve();
const FiberCompressiveForceLengthCurve& fkCurve
= get_FiberCompressiveForceLengthCurve();
const FiberCompressiveForceCosPennationCurve& fcphiCurve
= get_FiberCompressiveForceCosPennationCurve();
//Note the curves return normalized area. Each area must be un-normalized
mpei.fiberPotentialEnergy = fpeCurve.calcIntegral(mli.normFiberLength)
*(optFiberLength*maxIsoForce);
mpei.tendonPotentialEnergy= fseCurve.calcIntegral(mli.normTendonLength)
*(tendonSlackLen*maxIsoForce);
double compForceLengthPE= fkCurve.calcIntegral(mli.normFiberLength)
*(optFiberLength*maxIsoForce);
//Only the force dimension is normalized
double compForceCosPennationPE =
fcphiCurve.calcIntegral(mli.cosPennationAngle)*(maxIsoForce);
mpei.musclePotentialEnergy= mpei.fiberPotentialEnergy
+ mpei.tendonPotentialEnergy
+ compForceLengthPE
+ compForceCosPennationPE;
}
catch(const std::exception &x){
std::string msg = "Exception caught in Thelen2003Muscle::"
"calcMusclePotentialEnergyInfo\n"
"of " + getName() + "\n"
+ x.what();
throw OpenSim::Exception(msg);
}
}
void Millard2012AccelerationMuscle::
calcFiberVelocityInfo(const SimTK::State& s, FiberVelocityInfo& fvi) const
{
//ensureMuscleUpToDate();
SimTK_ASSERT(isObjectUpToDateWithProperties()==true,
"Millard2012AccelerationMuscle: Muscle is not"
" to date with properties");
double simTime = s.getTime(); //for debugging purposes
try{
//Get the quantities that we've already computed
const MuscleLengthInfo &mli = getMuscleLengthInfo(s);
//Get the static properties of this muscle
double mclLength = getLength(s);
double mclVelocity = getLengtheningSpeed(s);
double tendonSlackLen = getTendonSlackLength();
double optFiberLen = getOptimalFiberLength();
//Prep strings that will be useful to make sensible exception messages
std::string muscleName = getName();
std::string fcnName = ".calcFiberVelocityInfo";
std::string caller = muscleName;
caller.append(fcnName);
//=========================================================================
// Compute fv by inverting the force-velocity relationship in the
// equilibrium equations
//=========================================================================
//1. Get MuscleLengthInfo & available State information
double dlce = getStateVariableValue(s, STATE_FIBER_VELOCITY_NAME);
double dlceN1 = dlce/(getMaxContractionVelocity()*optFiberLen);
double lce = mli.fiberLength;
double phi = mli.pennationAngle;
double cosphi = mli.cosPennationAngle;
double sinphi = mli.sinPennationAngle;
double fal = mli.fiberActiveForceLengthMultiplier;