Rolling Resistance Linear Contact Model Implementation
See this page for the documentation of this contact model.
contactmodelrrlinear.h
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// contactmodelrrlinear.h
#include "contactmodel/src/contactmodelmechanical.h"
#ifdef rrlinear_LIB
# define rrlinear_EXPORT EXPORT_TAG
#elif defined(NO_MODEL_IMPORT)
# define rrlinear_EXPORT
#else
# define rrlinear_EXPORT IMPORT_TAG
#endif
namespace cmodelsxd {
using namespace itasca;
class ContactModelRRLinear : public ContactModelMechanical {
public:
// Constructor: Set default values for contact model properties.
rrlinear_EXPORT ContactModelRRLinear();
// Destructor, called when contact is deleted: free allocated memory, etc.
rrlinear_EXPORT virtual ~ContactModelRRLinear();
// Contact model name (used as keyword for commands and FISH).
virtual QString getName() const { return "rrlinear"; }
// The index provides a quick way to determine the type of contact model.
// Each type of contact model in PFC must have a unique index; this is assigned
// by PFC when the contact model is loaded. This index should be set to -1
virtual void setIndex(int i) { index_=i;}
virtual int getIndex() const {return index_;}
// Contact model version number (e.g., MyModel05_1). The version number can be
// accessed during the save-restore operation (within the archive method,
// testing {stream.getRestoreVersion() == getMinorVersion()} to allow for
// future modifications to the contact model data structure.
virtual uint getMinorVersion() const;
// Copy the state information to a newly created contact model.
// Provide access to state information, for use by copy method.
virtual void copy(const ContactModel *c);
// Provide save-restore capability for the state information.
virtual void archive(ArchiveStream &);
// Enumerator for the properties.
enum PropertyKeys {
kwKn=1
, kwKs
, kwFric
, kwLinF
, kwLinS
, kwLinMode
, kwRGap
, kwEmod
, kwKRatio
, kwDpNRatio
, kwDpSRatio
, kwDpMode
, kwDpF
, kwResFric
, kwResMoment
, kwResS
, kwResKr
, kwUserArea
};
// Contact model property names in a comma separated list. The order corresponds with
// the order of the PropertyKeys enumerator above. One can visualize any of these
// properties in PFC automatically.
virtual QString getProperties() const {
return "kn"
",ks"
",fric"
",lin_force"
",lin_slip"
",lin_mode"
",rgap"
",emod"
",kratio"
",dp_nratio"
",dp_sratio"
",dp_mode"
",dp_force"
",rr_fric"
",rr_moment"
",rr_slip"
",rr_kr"
",user_area" ;
}
// Enumerator for the energies.
enum EnergyKeys {
kwEStrain=1
, kwERRStrain
, kwESlip
, kwERRSlip
, kwEDashpot
};
// Contact model energy names in a comma separated list. The order corresponds with
// the order of the EnergyKeys enumerator above.
virtual QString getEnergies() const {
return "energy-strain"
",energy-rrstrain"
",energy-slip"
",energy-rrslip"
",energy-dashpot";
}
// Returns the value of the energy (base 1 - getEnergy(1) returns the estrain energy).
virtual double getEnergy(uint i) const;
// Returns whether or not each energy is accumulated (base 1 - getEnergyAccumulate(1)
// returns wther or not the estrain energy is accumulated which is false).
virtual bool getEnergyAccumulate(uint i) const;
// Set an energy value (base 1 - setEnergy(1) sets the estrain energy).
virtual void setEnergy(uint i,const double &d); // Base 1
// Activate the energy. This is only called if the energy tracking is enabled.
virtual void activateEnergy() { if (energies_) return; energies_ = NEWC(Energies());}
// Returns whether or not the energy tracking has been enabled for this contact.
virtual bool getEnergyActivated() const {return (energies_ != 0);}
// Enumerator for contact model related FISH callback events.
enum FishCallEvents {
fActivated=0
,fSlipChange
};
// Contact model FISH callback event names in a comma separated list. The order corresponds with
// the order of the FishCallEvents enumerator above.
virtual QString getFishCallEvents() const {
return
"contact_activated"
",slip_change";
}
// Return the specified contact model property.
virtual QVariant getProperty(uint i,const IContact *) const;
// The return value denotes whether or not the property corresponds to the global
// or local coordinate system (TRUE: global system, FALSE: local system). The
// local system is the contact-plane system (nst) defined as follows.
// If a vector V is expressed in the local system as (Vn, Vs, Vt), then V is
// expressed in the global system as {Vn*nc + Vs*sc + Vt*tc} where where nc, sc
// and tc are unit vectors in directions of the nst axes.
// This is used when rendering contact model properties that are vectors.
virtual bool getPropertyGlobal(uint i) const;
// Set the specified contact model property, ensuring that it is of the correct type
// and within the correct range --- if not, then throw an exception.
// The return value denotes whether or not the update has affected the timestep
// computation (by having modified the translational or rotational tangent stiffnesses).
// If true is returned, then the timestep will be recomputed.
virtual bool setProperty(uint i,const QVariant &v,IContact *);
// The return value denotes whether or not the property is read-only
// (TRUE: read-only, FALSE: read-write).
virtual bool getPropertyReadOnly(uint i) const;
// The return value denotes whether or not the property is inheritable
// (TRUE: inheritable, FALSE: not inheritable). Inheritance is provided by
// the endPropertyUpdated method.
virtual bool supportsInheritance(uint i) const;
// Return whether or not inheritance is enabled for the specified property.
virtual bool getInheritance(uint i) const { assert(i<32); quint32 mask = to<quint32>(1 << i); return (inheritanceField_ & mask) ? true : false; }
// Set the inheritance flag for the specified property.
virtual void setInheritance(uint i,bool b) { assert(i<32); quint32 mask = to<quint32>(1 << i); if (b) inheritanceField_ |= mask; else inheritanceField_ &= ~mask; }
// Enumerator for contact model methods.
enum MethodKeys { kwDeformability=1,kwArea};
// Contact model methoid names in a comma separated list. The order corresponds with
// the order of the MethodKeys enumerator above.
virtual QString getMethods() const { return "deformability,area";}
// Return a comma seprated list of the contact model method arguments (base 1).
virtual QString getMethodArguments(uint i) const;
// Set contact model method arguments (base 1).
// The return value denotes whether or not the update has affected the timestep
// computation (by having modified the translational or rotational tangent stiffnesses).
// If true is returned, then the timestep will be recomputed.
virtual bool setMethod(uint i,const QVector<QVariant> &vl,IContact *con=0);
// Prepare for entry into ForceDispLaw. The validate function is called when:
// (1) the contact is created, (2) a property of the contact that returns a true via
// the setProperty method has been modified and (3) when a set of cycles is executed
// via the {cycle N} command.
// Return value indicates contact activity (TRUE: active, FALSE: inactive).
virtual bool validate(ContactModelMechanicalState *state,const double ×tep);
// The endPropertyUpdated method is called whenever a surface property (with a name
// that matches an inheritable contact model property name) of one of the contacting
// pieces is modified. This allows the contact model to update its associated
// properties. The return value denotes whether or not the update has affected
// the time step computation (by having modified the translational or rotational
// tangent stiffnesses). If true is returned, then the time step will be recomputed.
virtual bool endPropertyUpdated(const QString &name,const IContactMechanical *c);
// The forceDisplacementLaw function is called during each cycle. Given the relative
// motion of the two contacting pieces (via
// state->relativeTranslationalIncrement_ (Ddn, Ddss, Ddst)
// state->relativeAngularIncrement_ (Dtt, Dtbs, Dtbt)
// Ddn : relative normal-displacement increment, Ddn > 0 is opening
// Ddss : relative shear-displacement increment (s-axis component)
// Ddst : relative shear-displacement increment (t-axis component)
// Dtt : relative twist-rotation increment
// Dtbs : relative bend-rotation increment (s-axis component)
// Dtbt : relative bend-rotation increment (t-axis component)
// The relative displacement and rotation increments:
// Dd = Ddn*nc + Ddss*sc + Ddst*tc
// Dt = Dtt*nc + Dtbs*sc + Dtbt*tc
// where nc, sc and tc are unit vectors in direc. of the nst axes, respectively.
// [see {Table 1: Contact State Variables} in PFC Model Components:
// Contacts and Contact Models: Contact Resolution]
// ) and the contact properties, this function must update the contact force and
// moment.
// The force_ is acting on piece 2, and is expressed in the local coordinate system
// (defined in getPropertyGlobal) such that the first component positive denotes
// compression. If we define the moment acting on piece 2 by Mc, and Mc is expressed
// in the local coordinate system (defined in getPropertyGlobal), then we must use the getMechanicalContact()->updateResultingTorquesLocal(...) method to
// get the total moment.
// The return value indicates the contact activity status (TRUE: active, FALSE:
// inactive) during the next cycle.
// Additional information:
// * If state->activated() is true, then the contact has just become active (it was
// inactive during the previous time step).
// * Fully elastic behavior is enforced during the SOLVE ELASTIC command by having
// the forceDispLaw handle the case of {state->canFail_ == true}.
virtual bool forceDisplacementLaw(ContactModelMechanicalState *state,const double ×tep);
// The getEffectiveXStiffness functions return the translational and rotational
// tangent stiffnesses used to compute a stable time step. When a contact is sliding,
// the translational tangent shear stiffness is zero (but this stiffness reduction
// is typically ignored when computing a stable time step). If the contact model
// includes a dashpot, then the translational stiffnesses must be increased (see
// Potyondy (2009)).
// [Potyondy, D. 'Stiffness Matrix at a Contact Between Two Clumps,' Itasca
// Consulting Group, Inc., Minneapolis, MN, Technical Memorandum ICG6863-L,
// December 7, 2009.]
virtual DVect2 getEffectiveTranslationalStiffness() const { return effectiveTranslationalStiffness_; }
virtual DAVect getEffectiveRotationalStiffness() const { return effectiveRotationalStiffness_;}
// Return a new instance of the contact model. This is used in the CMAT
// when a new contact is created.
virtual ContactModelRRLinear *clone() const { return NEWC(ContactModelRRLinear()); }
// The getActivityDistance function is called by the contact-resolution logic when
// the CMAT is modified. Return value is the activity distance used by the
// checkActivity function.
virtual double getActivityDistance() const {return rgap_;}
// The isOKToDelete function is called by the contact-resolution logic when...
// Return value indicates whether or not the contact may be deleted.
// If TRUE, then the contact may be deleted when it is inactive.
// If FALSE, then the contact may not be deleted (under any condition).
virtual bool isOKToDelete() const { return !isBonded(); }
// Zero the forces and moments stored in the contact model. This function is called
// when the contact becomes inactive.
virtual void resetForcesAndMoments() {
lin_F(DVect(0.0));
dp_F(DVect(0.0));
res_M(DAVect(0.0));
if (energies_) {
energies_->estrain_ = 0.0;
energies_->errstrain_ = 0.0;
}
}
virtual void setForce(const DVect &v,IContact *c);
virtual void setArea(const double &d) { userArea_ = d; }
// The checkActivity function is called by the contact-resolution logic when...
// Return value indicates contact activity (TRUE: active, FALSE: inactive).
virtual bool checkActivity(const double &gap) { return gap <= rgap_; }
// Returns the sliding state (FALSE is returned if not implemented).
virtual bool isSliding() const { return lin_S_; }
// Returns the bonding state (FALSE is returned if not implemented).
virtual bool isBonded() const { return false; }
// Both of these methods are called only for contacts with facets where the wall
// resolution scheme is set the full. In such cases one might wish to propagate
// contact state information (e.g., shear force) from one active contact to another.
// See the Faceted Wall section in the documentation.
virtual void propagateStateInformation(IContactModelMechanical* oldCm,const CAxes &oldSystem=CAxes(),const CAxes &newSystem=CAxes());
virtual void setNonForcePropsFrom(IContactModel *oldCM);
/// Return the total force that the contact model holds.
virtual DVect getForce(const IContactMechanical *) const;
/// Return the total moment on 1 that the contact model holds
virtual DAVect getMomentOn1(const IContactMechanical *) const;
/// Return the total moment on 1 that the contact model holds
virtual DAVect getMomentOn2(const IContactMechanical *) const;
// Methods to get and set properties.
const double & kn() const {return kn_;}
void kn(const double &d) {kn_=d;}
const double & ks() const {return ks_;}
void ks(const double &d) {ks_=d;}
const double & fric() const {return fric_;}
void fric(const double &d) {fric_=d;}
const DVect & lin_F() const {return lin_F_;}
void lin_F(const DVect &f) { lin_F_=f;}
bool lin_S() const {return lin_S_;}
void lin_S(bool b) { lin_S_=b;}
uint lin_mode() const {return lin_mode_;}
void lin_mode(uint i) { lin_mode_= i;}
const double & rgap() const {return rgap_;}
void rgap(const double &d) {rgap_=d;}
bool hasDamping() const {return dpProps_ ? true : false;}
double dp_nratio() const {return (hasDamping() ? (dpProps_->dp_nratio_) : 0.0);}
void dp_nratio(const double &d) { if(!hasDamping()) return; dpProps_->dp_nratio_=d;}
double dp_sratio() const {return hasDamping() ? dpProps_->dp_sratio_: 0.0;}
void dp_sratio(const double &d) { if(!hasDamping()) return; dpProps_->dp_sratio_=d;}
int dp_mode() const {return hasDamping() ? dpProps_->dp_mode_: -1;}
void dp_mode(int i) { if(!hasDamping()) return; dpProps_->dp_mode_=i;}
DVect dp_F() const {return hasDamping() ? dpProps_->dp_F_: DVect(0.0);}
void dp_F(const DVect &f) { if(!hasDamping()) return; dpProps_->dp_F_=f;}
bool hasEnergies() const {return energies_ ? true:false;}
double estrain() const {return hasEnergies() ? energies_->estrain_: 0.0;}
void estrain(const double &d) { if(!hasEnergies()) return; energies_->estrain_=d;}
double errstrain() const {return hasEnergies() ? energies_->errstrain_: 0.0;}
void errstrain(const double &d) { if(!hasEnergies()) return; energies_->errstrain_=d;}
double eslip() const {return hasEnergies() ? energies_->eslip_: 0.0;}
void eslip(const double &d) { if(!hasEnergies()) return; energies_->eslip_=d;}
double errslip() const {return hasEnergies() ? energies_->errslip_: 0.0;}
void errslip(const double &d) { if(!hasEnergies()) return; energies_->errslip_=d;}
double edashpot() const {return hasEnergies() ? energies_->edashpot_: 0.0;}
void edashpot(const double &d) { if(!hasEnergies()) return; energies_->edashpot_=d;}
uint inheritanceField() const {return inheritanceField_;}
void inheritanceField(uint i) {inheritanceField_ = i;}
const DVect2 & effectiveTranslationalStiffness() const {return effectiveTranslationalStiffness_;}
void effectiveTranslationalStiffness(const DVect2 &v ) {effectiveTranslationalStiffness_=v;}
const DAVect & effectiveRotationalStiffness() const {return effectiveRotationalStiffness_;}
void effectiveRotationalStiffness(const DAVect &v ) {effectiveRotationalStiffness_=v;}
// Rolling resistance methods
const double & res_fric() const {return res_fric_;}
void res_fric(const double &d) {res_fric_=d;}
const DAVect & res_M() const {return res_M_;}
void res_M(const DAVect &f) { res_M_=f;}
bool res_S() const {return res_S_;}
void res_S(bool b) { res_S_=b;}
const double & kr() const {return kr_;}
void kr(const double &d) {kr_=d;}
const double & fr() const {return fr_;}
void fr(const double &d) {fr_=d;}
private:
// Index - used internally by PFC. Should be set to -1 in the cpp file.
static int index_;
// Structure to store the energies.
struct Energies {
Energies() : estrain_(0.0),errstrain_(0.0),eslip_(0.0),errslip_(0.0),edashpot_(0.0) {}
double estrain_; // elastic energy stored in linear group
double errstrain_; // elastic energy stored in rolling resistance group
double eslip_; // work dissipated by friction
double errslip_; // work dissipated by rolling resistance friction
double edashpot_; // work dissipated by dashpots
};
// Structure to store dashpot quantities.
struct dpProps {
dpProps() : dp_nratio_(0.0), dp_sratio_(0.0), dp_mode_(0), dp_F_(DVect(0.0)) {}
double dp_nratio_; // normal viscous critical damping ratio
double dp_sratio_; // shear viscous critical damping ratio
int dp_mode_; // for viscous mode (0-4) 0 = dashpots, 1 = tensile limit, 2 = shear limit, 3 = limit both
DVect dp_F_; // Force in the dashpots
};
bool updateKn(const IContactMechanical *con);
bool updateKs(const IContactMechanical *con);
bool updateFric(const IContactMechanical *con);
bool updateResFric(const IContactMechanical *con);
void updateStiffness(ContactModelMechanicalState *state);
void setDampCoefficients(const double &mass,double *vcn,double *vcs);
// Contact model inheritance fields.
quint32 inheritanceField_;
// Effective translational stiffness.
DVect2 effectiveTranslationalStiffness_;
DAVect effectiveRotationalStiffness_; // (Twisting,Bending,Bending) Rotational stiffness (twisting always 0)
// linear model properties
double kn_; // Normal stiffness
double ks_; // Shear stiffness
double fric_; // Coulomb friction coefficient
DVect lin_F_; // Force carried in the linear model
bool lin_S_; // The current slip state
uint lin_mode_; // Specifies absolute (0) or incremental (1) calculation mode
double rgap_; // Reference gap
dpProps * dpProps_; // The viscous properties
// rolling resistance properties
double res_fric_; // rolling friction coefficient
DAVect res_M_; // moment (bending only)
bool res_S_; // The current rolling resistance slip state
double kr_; // bending rotational stiffness (read-only, calculated internaly)
double fr_; // rolling friction coefficient (rbar*res_fric_) (calculated internaly, not a property)
double userArea_; // Area as specified by the user
Energies * energies_; // The energies
};
} // namespace cmodelsxd
// EoF
|
contactmodelrrlinear.cpp
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#include "contactmodelrrlinear.h"
#include "module/interface/icontactmechanical.h"
#include "module/interface/icontact.h"
#include "module/interface/ipiecemechanical.h"
#include "module/interface/ipiece.h"
#include "module/interface/ifishcalllist.h"
#include "../version.txt"
#include "utility/src/tptr.h"
#include "shared/src/mathutil.h"
#include "kernel/interface/iprogram.h"
#include "module/interface/icontactthermal.h"
#include "contactmodel/src/contactmodelthermal.h"
#ifdef rrlinear_LIB
int __stdcall DllMain(void *,unsigned, void *) {
return 1;
}
extern "C" EXPORT_TAG const char *getName() {
#if DIM==3
return "contactmodelmechanical3drrlinear";
#else
return "contactmodelmechanical2drrlinear";
#endif
}
extern "C" EXPORT_TAG unsigned getMajorVersion() {
return MAJOR_VERSION;
}
extern "C" EXPORT_TAG unsigned getMinorVersion() {
return MINOR_VERSION;
}
extern "C" EXPORT_TAG void *createInstance() {
cmodelsxd::ContactModelRRLinear *m = NEWC(cmodelsxd::ContactModelRRLinear());
return (void *)m;
}
#endif
namespace cmodelsxd {
static const quint32 linKnMask = 0x00000002; // Base 1!
static const quint32 linKsMask = 0x00000004;
static const quint32 linFricMask = 0x00000008;
static const quint32 resFricMask = 0x00004000;
using namespace itasca;
int ContactModelRRLinear::index_ = -1;
UInt ContactModelRRLinear::getMinorVersion() const { return MINOR_VERSION;}
ContactModelRRLinear::ContactModelRRLinear() : inheritanceField_(linKnMask|linKsMask|linFricMask|resFricMask)
, effectiveTranslationalStiffness_(DVect2(0.0))
, effectiveRotationalStiffness_(DAVect(0.0))
, kn_(0.0)
, ks_(0.0)
, fric_(0.0)
, lin_F_(DVect(0.0))
, lin_S_(false)
, lin_mode_(0)
, rgap_(0.0)
, dpProps_(0)
, res_fric_(0.0)
, res_M_(DAVect(0.0))
, res_S_(false)
, kr_(0.0)
, fr_(0.0)
, userArea_(0.0)
, energies_(0) {
}
ContactModelRRLinear::~ContactModelRRLinear() {
// Make sure to clean up after yourself!
if (dpProps_)
delete dpProps_;
if (energies_)
delete energies_;
}
void ContactModelRRLinear::archive(ArchiveStream &stream) {
// The stream allows one to archive the values of the contact model
// so that it can be saved and restored. The minor version can be
// used here to allow for incremental changes to the contact model too.
stream & kn_;
stream & ks_;
stream & fric_;
stream & lin_F_;
stream & lin_S_;
stream & lin_mode_;
stream & rgap_;
stream & res_fric_;
stream & res_M_;
stream & res_S_;
stream & kr_;
stream & fr_;
if (stream.getArchiveState()==ArchiveStream::Save) {
bool b = false;
if (dpProps_) {
b = true;
stream & b;
stream & dpProps_->dp_nratio_;
stream & dpProps_->dp_sratio_;
stream & dpProps_->dp_mode_;
stream & dpProps_->dp_F_;
}
else
stream & b;
b = false;
if (energies_) {
b = true;
stream & b;
stream & energies_->estrain_;
stream & energies_->errstrain_;
stream & energies_->eslip_;
stream & energies_->errslip_;
stream & energies_->edashpot_;
}
else
stream & b;
} else {
bool b(false);
stream & b;
if (b) {
if (!dpProps_)
dpProps_ = NEWC(dpProps());
stream & dpProps_->dp_nratio_;
stream & dpProps_->dp_sratio_;
stream & dpProps_->dp_mode_;
stream & dpProps_->dp_F_;
}
stream & b;
if (b) {
if (!energies_)
energies_ = NEWC(Energies());
stream & energies_->estrain_;
stream & energies_->errstrain_;
stream & energies_->eslip_;
stream & energies_->errslip_;
stream & energies_->edashpot_;
}
}
stream & inheritanceField_;
stream & effectiveTranslationalStiffness_;
stream & effectiveRotationalStiffness_;
if (stream.getArchiveState() == ArchiveStream::Save || stream.getRestoreVersion() >= 20)
stream & userArea_;
}
void ContactModelRRLinear::copy(const ContactModel *cm) {
// Copy all of the contact model properties. Used in the CMAT
// when a new contact is created.
ContactModelMechanical::copy(cm);
const ContactModelRRLinear *in = dynamic_cast<const ContactModelRRLinear*>(cm);
if (!in) throw std::runtime_error("Internal error: contact model dynamic cast failed.");
kn(in->kn());
ks(in->ks());
fric(in->fric());
lin_F(in->lin_F());
lin_S(in->lin_S());
lin_mode(in->lin_mode());
rgap(in->rgap());
res_fric(in->res_fric());
res_M(in->res_M());
res_S(in->res_S());
kr(in->kr());
fr(in->fr());
if (in->hasDamping()) {
if (!dpProps_)
dpProps_ = NEWC(dpProps());
dp_nratio(in->dp_nratio());
dp_sratio(in->dp_sratio());
dp_mode(in->dp_mode());
dp_F(in->dp_F());
}
if (in->hasEnergies()) {
if (!energies_)
energies_ = NEWC(Energies());
estrain(in->estrain());
errstrain(in->errstrain());
eslip(in->eslip());
errslip(in->errslip());
edashpot(in->edashpot());
}
userArea_ = in->userArea_;
inheritanceField(in->inheritanceField());
effectiveTranslationalStiffness(in->effectiveTranslationalStiffness());
effectiveRotationalStiffness(in->effectiveRotationalStiffness());
}
QVariant ContactModelRRLinear::getProperty(uint i,const IContact *con) const {
// Return the property. The IContact pointer is provided so that
// more complicated properties, depending on contact characteristics,
// can be calcualted.
QVariant var;
switch (i) {
case kwKn: return kn_;
case kwKs: return ks_;
case kwFric: return fric_;
case kwLinF: var.setValue(lin_F_); return var;
case kwLinS: return lin_S_;
case kwLinMode: return lin_mode_;
case kwRGap: return rgap_;
case kwEmod: {
const IContactMechanical *c(convert_getcast<IContactMechanical>(con));
if (c ==nullptr) return 0.0;
double rsq(std::max(c->getEnd1Curvature().y(),c->getEnd2Curvature().y()));
double rsum(0.0);
if (c->getEnd1Curvature().y())
rsum += 1.0/c->getEnd1Curvature().y();
if (c->getEnd2Curvature().y())
rsum += 1.0/c->getEnd2Curvature().y();
if (userArea_) {
#ifdef THREED
rsq = std::sqrt(userArea_ / dPi);
#else
rsq = userArea_ / 2.0;
#endif
rsum = rsq + rsq;
rsq = 1. / rsq;
}
#ifdef TWOD
return (kn_ * rsum * rsq / 2.0);
#else
return (kn_ * rsum * rsq * rsq) / dPi;
#endif
}
case kwKRatio: return (ks_ == 0.0) ? 0.0 : (kn_/ks_);
case kwDpNRatio: return dpProps_ ? dpProps_->dp_nratio_ : 0;
case kwDpSRatio: return dpProps_ ? dpProps_->dp_sratio_ : 0;
case kwDpMode: return dpProps_ ? dpProps_->dp_mode_ : 0;
case kwDpF: {
dpProps_ ? var.setValue(dpProps_->dp_F_) : var.setValue(DVect(0.0));
return var;
}
case kwResFric: return res_fric_;
case kwResMoment: var.setValue(res_M_); return var;
case kwResS: return res_S_;
case kwResKr: return kr_;
case kwUserArea: return userArea_;
}
assert(0);
return QVariant();
}
bool ContactModelRRLinear::getPropertyGlobal(uint i) const {
// Returns whether or not a property is held in the global axis system (TRUE)
// or the local system (FALSE). Used by the plotting logic.
switch (i) {
case kwLinF:
case kwDpF:
case kwResMoment:
return false;
}
return true;
}
bool ContactModelRRLinear::setProperty(uint i,const QVariant &v,IContact *) {
// Set a contact model property. Return value indicates that the timestep
// should be recalculated.
dpProps dp;
switch (i) {
case kwKn: {
if (!v.canConvert<double>())
throw Exception("kn must be a double.");
double val(v.toDouble());
if (val<0.0)
throw Exception("Negative kn not allowed.");
kn_ = val;
return true;
}
case kwKs: {
if (!v.canConvert<double>())
throw Exception("ks must be a double.");
double val(v.toDouble());
if (val<0.0)
throw Exception("Negative ks not allowed.");
ks_ = val;
return true;
}
case kwFric: {
if (!v.canConvert<double>())
throw Exception("fric must be a double.");
double val(v.toDouble());
if (val<0.0)
throw Exception("Negative fric not allowed.");
fric_ = val;
return false;
}
case kwLinF: {
if (!v.canConvert<DVect>())
throw Exception("lin_force must be a vector.");
DVect val(v.value<DVect>());
lin_F_ = val;
return false;
}
case kwLinMode: {
if (!v.canConvert<uint>())
throw Exception("lin_mode must be 0 (absolute) or 1 (incremental).");
uint val(v.toUInt());
if (val >1)
throw Exception("lin_mode must be 0 (absolute) or 1 (incremental).");
lin_mode_ = val;
return false;
}
case kwRGap: {
if (!v.canConvert<double>())
throw Exception("Reference gap must be a double.");
double val(v.toDouble());
rgap_ = val;
return false;
}
case kwDpNRatio: {
if (!v.canConvert<double>())
throw Exception("dp_nratio must be a double.");
double val(v.toDouble());
if (val<0.0)
throw Exception("Negative dp_nratio not allowed.");
if (val == 0.0 && !dpProps_)
return false;
if (!dpProps_)
dpProps_ = NEWC(dpProps());
dpProps_->dp_nratio_ = val;
return true;
}
case kwDpSRatio: {
if (!v.canConvert<double>())
throw Exception("dp_sratio must be a double.");
double val(v.toDouble());
if (val<0.0)
throw Exception("Negative dp_sratio not allowed.");
if (val == 0.0 && !dpProps_)
return false;
if (!dpProps_)
dpProps_ = NEWC(dpProps());
dpProps_->dp_sratio_ = val;
return true;
}
case kwDpMode: {
if (!v.canConvert<int>())
throw Exception("The viscous mode dp_mode must be 0, 1, 2, or 3.");
int val(v.toInt());
if (val == 0 && !dpProps_)
return false;
if (val < 0 || val > 3)
throw Exception("The viscous mode dp_mode must be 0, 1, 2, or 3.");
if (!dpProps_)
dpProps_ = NEWC(dpProps());
dpProps_->dp_mode_ = val;
return false;
}
case kwDpF: {
if (!v.canConvert<DVect>())
throw Exception("dp_force must be a vector.");
DVect val(v.value<DVect>());
if (val.fsum() == 0.0 && !dpProps_)
return false;
if (!dpProps_)
dpProps_ = NEWC(dpProps());
dpProps_->dp_F_ = val;
return false;
}
case kwResFric: {
if (!v.canConvert<double>())
throw Exception("res_fric must be a double.");
double val(v.toDouble());
if (val<0.0)
throw Exception("Negative res_fric not allowed.");
res_fric_ = val;
return false;
}
case kwResMoment: {
DAVect val(0.0);
#ifdef TWOD
if (!v.canConvert<DAVect>() && !v.canConvert<double>())
throw Exception("res_moment must be an angular vector.");
if (v.canConvert<DAVect>())
val = DAVect(v.value<DAVect>());
else
val = DAVect(v.toDouble());
#else
if (!v.canConvert<DAVect>() && !v.canConvert<DVect>())
throw Exception("res_moment must be an angular vector.");
if (v.canConvert<DAVect>())
val = DAVect(v.value<DAVect>());
else
val = DAVect(v.value<DVect>());
#endif
res_M_ = val;
return false;
}
case kwUserArea: {
if (!v.canConvert<double>())
throw Exception("user_area must be a double.");
double val(v.toDouble());
if (val < 0.0)
throw Exception("Negative user_area not allowed.");
userArea_ = val;
return true;
}
}
return false;
}
bool ContactModelRRLinear::getPropertyReadOnly(uint i) const {
// Returns TRUE if a property is read only or FALSE otherwise.
switch (i) {
case kwDpF:
case kwLinS:
case kwEmod:
case kwKRatio:
case kwResS:
case kwResKr:
return true;
default:
break;
}
return false;
}
bool ContactModelRRLinear::supportsInheritance(uint i) const {
// Returns TRUE if a property supports inheritance or FALSE otherwise.
switch (i) {
case kwKn:
case kwKs:
case kwFric:
case kwResFric:
return true;
default:
break;
}
return false;
}
QString ContactModelRRLinear::getMethodArguments(uint i) const {
// Return a list of contact model method argument names.
switch (i) {
case kwDeformability:
return "emod,kratio";
case kwArea:
return QString();
}
assert(0);
return QString();
}
bool ContactModelRRLinear::setMethod(uint i,const QVector<QVariant> &vl,IContact *con) {
// Apply the specified method.
IContactMechanical *c(convert_getcast<IContactMechanical>(con));
switch (i) {
case kwDeformability: {
double emod;
double krat;
if (vl.at(0).isNull())
throw Exception("Argument emod must be specified with method deformability in contact model %1.",getName());
emod = vl.at(0).toDouble();
if (emod<0.0)
throw Exception("Negative emod not allowed in contact model %1.",getName());
if (vl.at(1).isNull())
throw Exception("Argument kratio must be specified with method deformability in contact model %1.",getName());
krat = vl.at(1).toDouble();
if (krat<0.0)
throw Exception("Negative stiffness ratio not allowed in contact model %1.",getName());
double rsq(std::max(c->getEnd1Curvature().y(),c->getEnd2Curvature().y()));
double rsum(0.0);
if (c->getEnd1Curvature().y())
rsum += 1.0/c->getEnd1Curvature().y();
if (c->getEnd2Curvature().y())
rsum += 1.0/c->getEnd2Curvature().y();
if (userArea_) {
#ifdef THREED
rsq = std::sqrt(userArea_ / dPi);
#else
rsq = userArea_ / 2.0;
#endif
rsum = rsq + rsq;
rsq = 1. / rsq;
}
#ifdef TWOD
kn_ = 2.0 * emod / (rsq * rsum);
#else
kn_ = dPi * emod / (rsq * rsq * rsum);
#endif
ks_ = (krat == 0.0) ? 0.0 : kn_ / krat;
setInheritance(1,false);
setInheritance(2,false);
return true;
}
case kwArea: {
if (!userArea_) {
double rsq(1./std::max(c->getEnd1Curvature().y(),c->getEnd2Curvature().y()));
#ifdef THREED
userArea_ = rsq * rsq * dPi;
#else
userArea_ = rsq * 2.0;
#endif
}
return true;
}
}
return false;
}
double ContactModelRRLinear::getEnergy(uint i) const {
// Return an energy value.
double ret(0.0);
if (!energies_)
return ret;
switch (i) {
case kwEStrain: return energies_->estrain_;
case kwERRStrain: return energies_->errstrain_;
case kwESlip: return energies_->eslip_;
case kwERRSlip: return energies_->errslip_;
case kwEDashpot: return energies_->edashpot_;
}
assert(0);
return ret;
}
bool ContactModelRRLinear::getEnergyAccumulate(uint i) const {
// Returns TRUE if the corresponding energy is accumulated or FALSE otherwise.
switch (i) {
case kwEStrain: return false;
case kwERRStrain: return false;
case kwESlip: return true;
case kwERRSlip: return true;
case kwEDashpot: return true;
}
assert(0);
return false;
}
void ContactModelRRLinear::setEnergy(uint i,const double &d) {
// Set an energy value.
if (!energies_) return;
switch (i) {
case kwEStrain: energies_->estrain_ = d; return;
case kwERRStrain: energies_->errstrain_ = d; return;
case kwESlip: energies_->eslip_ = d; return;
case kwERRSlip: energies_->errslip_ = d; return;
case kwEDashpot: energies_->edashpot_= d; return;
}
assert(0);
return;
}
bool ContactModelRRLinear::validate(ContactModelMechanicalState *state,const double &) {
// Validate the / Prepare for entry into ForceDispLaw. The validate function is called when:
// (1) the contact is created, (2) a property of the contact that returns a true via
// the setProperty method has been modified and (3) when a set of cycles is executed
// via the {cycle N} command.
// Return value indicates contact activity (TRUE: active, FALSE: inactive).
assert(state);
const IContactMechanical *c = state->getMechanicalContact();
assert(c);
if (state->trackEnergy_)
activateEnergy();
if (inheritanceField_ & linKnMask)
updateKn(c);
if (inheritanceField_ & linKsMask)
updateKs(c);
if (inheritanceField_ & linFricMask)
updateFric(c);
if (inheritanceField_ & resFricMask)
updateResFric(c);
updateStiffness(state);
return checkActivity(state->gap_);
}
static const QString knstr("kn");
bool ContactModelRRLinear::updateKn(const IContactMechanical *con) {
assert(con);
QVariant v1 = con->getEnd1()->getProperty(knstr);
QVariant v2 = con->getEnd2()->getProperty(knstr);
if (!v1.isValid() || !v2.isValid())
return false;
double kn1 = v1.toDouble();
double kn2 = v2.toDouble();
double val = kn_;
if (kn1 && kn2)
kn_ = kn1*kn2/(kn1+kn2);
else if (kn1)
kn_ = kn1;
else if (kn2)
kn_ = kn2;
return ( (kn_ != val) );
}
static const QString ksstr("ks");
bool ContactModelRRLinear::updateKs(const IContactMechanical *con) {
assert(con);
QVariant v1 = con->getEnd1()->getProperty(ksstr);
QVariant v2 = con->getEnd2()->getProperty(ksstr);
if (!v1.isValid() || !v2.isValid())
return false;
double ks1 = v1.toDouble();
double ks2 = v2.toDouble();
double val = ks_;
if (ks1 && ks2)
ks_ = ks1*ks2/(ks1+ks2);
else if (ks1)
ks_ = ks1;
else if (ks2)
ks_ = ks2;
return ( (ks_ != val) );
}
static const QString fricstr("fric");
bool ContactModelRRLinear::updateFric(const IContactMechanical *con) {
assert(con);
QVariant v1 = con->getEnd1()->getProperty(fricstr);
QVariant v2 = con->getEnd2()->getProperty(fricstr);
if (!v1.isValid() || !v2.isValid())
return false;
double fric1 = std::max(0.0,v1.toDouble());
double fric2 = std::max(0.0,v2.toDouble());
double val = fric_;
fric_ = std::min(fric1,fric2);
return ( (fric_ != val) );
}
static const QString rfricstr("rr_fric");
bool ContactModelRRLinear::updateResFric(const IContactMechanical *con) {
assert(con);
QVariant v1 = con->getEnd1()->getProperty(rfricstr);
QVariant v2 = con->getEnd2()->getProperty(rfricstr);
if (!v1.isValid() || !v2.isValid())
return false;
double rfric1 = std::max(0.0,v1.toDouble());
double rfric2 = std::max(0.0,v2.toDouble());
double val = res_fric_;
res_fric_ = std::min(rfric1,rfric2);
return ( (res_fric_ != val) );
}
bool ContactModelRRLinear::endPropertyUpdated(const QString &name,const IContactMechanical *c) {
// The endPropertyUpdated method is called whenever a surface property (with a name
// that matches an inheritable contact model property name) of one of the contacting
// pieces is modified. This allows the contact model to update its associated
// properties. The return value denotes whether or not the update has affected
// the time step computation (by having modified the translational or rotational
// tangent stiffnesses). If true is returned, then the time step will be recomputed.
assert(c);
QStringList availableProperties = getProperties().simplified().replace(" ","").split(",",QString::SkipEmptyParts);
QRegExp rx(name,Qt::CaseInsensitive);
int idx = availableProperties.indexOf(rx)+1;
bool ret=false;
if (idx<=0)
return ret;
switch(idx) {
case kwKn: { //kn
if (inheritanceField_ & linKnMask)
ret = updateKn(c);
break;
}
case kwKs: { //ks
if (inheritanceField_ & linKsMask)
ret =updateKs(c);
break;
}
case kwFric: { //fric
if (inheritanceField_ & linFricMask)
updateFric(c);
break;
}
case kwResFric: { //rr_fric
if (inheritanceField_ & resFricMask)
ret = updateResFric(c);
break;
}
}
return ret;
}
void ContactModelRRLinear::updateStiffness(ContactModelMechanicalState *state) {
// first compute rolling resistance stiffness
kr_ = 0.0;
if (res_fric_ > 0.0) {
double rbar = 0.0;
double r1 = 1.0/state->end1Curvature_.y();
rbar = r1;
double r2 = 0.0;
if (state->end2Curvature_.y()) {
r2 = 1.0 / state->end2Curvature_.y();
rbar = (r1*r2) / (r1+r2);
}
if (userArea_) {
#ifdef THREED
r1 = std::sqrt(userArea_ / dPi);
#else
r1 = userArea_ / 2.0;
#endif
rbar = r1/2.0;
}
kr_ = ks_*rbar*rbar;
fr_ = res_fric_*rbar;
}
// Now calculate effective stiffness
DVect2 retT(kn_,ks_);
// correction if viscous damping active
if (dpProps_) {
DVect2 correct(1.0);
if (dpProps_->dp_nratio_)
correct.rx() = sqrt(1.0+dpProps_->dp_nratio_*dpProps_->dp_nratio_) - dpProps_->dp_nratio_;
if (dpProps_->dp_sratio_)
correct.ry() = sqrt(1.0+dpProps_->dp_sratio_*dpProps_->dp_sratio_) - dpProps_->dp_sratio_;
retT /= (correct*correct);
}
effectiveTranslationalStiffness_ = retT;
// Effective rotational stiffness (bending only)
effectiveRotationalStiffness_ = DAVect(kr_);
#if DIM==3
effectiveRotationalStiffness_.rx() = 0.0;
#endif
}
bool ContactModelRRLinear::forceDisplacementLaw(ContactModelMechanicalState *state,const double ×tep) {
assert(state);
// Current overlap
double overlap = rgap_ - state->gap_;
// Relative translational increment
DVect trans = state->relativeTranslationalIncrement_;
// Correction factor to account for when the contact becomes newly active.
// We estimate the time of activity during the timestep when the contact has first
// become active and scale the forces accordingly.
double correction = 1.0;
// The contact was just activated from an inactive state
if (state->activated()) {
// Trigger the FISH callback if one is hooked up to the
// contact_activated event.
if (cmEvents_[fActivated] >= 0) {
// An FArray of QVariant is returned and these will be passed
// to the FISH function as an array of FISH symbols as the second
// argument to the FISH callback function.
FArray<QVariant,2> arg;
QVariant v;
// Just put a pointer to the contact in the array and return it.
IContact * c = const_cast<IContact*>(state->getContact());
TPtr<IThing> t(c->getIThing());
v.setValue(t);
arg.push_back(v);
IFishCallList *fi = const_cast<IFishCallList*>(state->getProgram()->findInterface<IFishCallList>());
fi->setCMFishCallArguments(c,arg,cmEvents_[fActivated]);
}
// Calculate the correction factor.
if (lin_mode_ == 0 && trans.x()) {
correction = -1.0*overlap / trans.x();
if (correction < 0)
correction = 1.0;
}
}
// Angular dispacement increment.
DAVect ang = state->relativeAngularIncrement_;
DVect lin_F_old = lin_F_;
if (lin_mode_ == 0)
lin_F_.rx() = overlap * kn_; // incremental mode for normal force calculation
else
lin_F_.rx() -= correction * trans.x() * kn_; // absolute mode for normal force calculation
// Normal force can only be positive.
lin_F_.rx() = std::max(0.0,lin_F_.x());
// Calculate the shear force.
DVect sforce(0.0);
// dim holds the dimension (e.g., 2 for 2D and 3 for 3D)
// Loop over the shear components (note: the 0 component is the normal component)
// and calculate the shear force.
for (int i=1; i<dim; ++i)
sforce.rdof(i) = lin_F_.dof(i) - trans.dof(i) * ks_ * correction;
// The canFail flag corresponds to whether or not the contact can undergo non-linear
// force-displacement response. If the SOLVE ELASTIC command is given then the
// canFail state is set to FALSE. Otherwise it is always TRUE.
if (state->canFail_) {
// Resolve sliding. This is the normal force multiplied by the coefficient of friction.
double crit = lin_F_.x() * fric_;
// The is the magnitude of the shear force.
double sfmag = sforce.mag();
// Sliding occurs when the magnitude of the shear force is greater than the
// critical value.
if (sfmag > crit) {
// Lower the shear force to the critical value for sliding.
double rat = crit / sfmag;
sforce *= rat;
// Handle the slip_change event if one has been hooked up. Sliding has commenced.
if (!lin_S_ && cmEvents_[fSlipChange] >= 0) {
FArray<QVariant,3> arg;
QVariant p1;
// Put a pointer to the contact in the array plus 0 to indicate slip has initiated.
IContact * c = const_cast<IContact*>(state->getContact());
TPtr<IThing> t(c->getIThing());
p1.setValue(t);
arg.push_back(p1);
p1.setValue(0);
arg.push_back(p1);
IFishCallList *fi = const_cast<IFishCallList*>(state->getProgram()->findInterface<IFishCallList>());
fi->setCMFishCallArguments(c,arg,cmEvents_[fSlipChange]);
}
lin_S_ = true;
} else {
// Handle the slip_change event if one has been hooked up and
// the contact was previously sliding. Sliding has ceased.
if (lin_S_) {
if (cmEvents_[fSlipChange] >= 0) {
FArray<QVariant,3> arg;
QVariant p1;
// Put a pointer to the contact in the array plus 1 to indicate slip has ceased.
IContact * c = const_cast<IContact*>(state->getContact());
TPtr<IThing> t(c->getIThing());
p1.setValue(t);
arg.push_back(p1);
p1.setValue(1);
arg.push_back(p1);
IFishCallList *fi = const_cast<IFishCallList*>(state->getProgram()->findInterface<IFishCallList>());
fi->setCMFishCallArguments(c,arg,cmEvents_[fSlipChange]);
}
lin_S_ = false;
}
}
}
// Set the shear components of the total force.
for (int i=1; i<dim; ++i)
lin_F_.rdof(i) = sforce.dof(i);
// Rolling resistance
DAVect res_M_old = res_M_;
if ((fr_ == 0.0) || (kr_==0.0)) {
res_M_.fill(0.0);
} else {
DAVect angStiff(0.0);
DAVect MomentInc(0.0);
#if DIM==3
angStiff.rx() = 0.0;
angStiff.ry() = kr_;
#endif
angStiff.rz() = kr_;
MomentInc = ang * angStiff * (-1.0);
res_M_ += MomentInc;
if (state->canFail_) {
// Account for bending strength
double rmax = std::abs(fr_*lin_F_.x());
double rmag = res_M_.mag();
if (rmag > rmax) {
double fac = rmax/rmag;
res_M_ *= fac;
res_S_ = true;
} else {
res_S_ = false;
}
}
}
// Account for dashpot forces if the dashpot structure has been defined.
if (dpProps_) {
dpProps_->dp_F_.fill(0.0);
double vcn(0.0), vcs(0.0);
// Calculate the damping coefficients.
setDampCoefficients(state->inertialMass_,&vcn,&vcs);
// First damp the shear components
for (int i=1; i<dim; ++i)
dpProps_->dp_F_.rdof(i) = trans.dof(i) * (-1.0* vcs) / timestep;
// Damp the normal component
dpProps_->dp_F_.rx() -= trans.x() * vcn / timestep;
// Need to change behavior based on the dp_mode.
if ((dpProps_->dp_mode_ == 1 || dpProps_->dp_mode_ == 3)) {
// Limit in tension if not bonded.
if (dpProps_->dp_F_.x() + lin_F_.x() < 0)
dpProps_->dp_F_.rx() = - lin_F_.rx();
}
if (lin_S_ && dpProps_->dp_mode_ > 1) {
// Limit in shear if not sliding.
double dfn = dpProps_->dp_F_.rx();
dpProps_->dp_F_.fill(0.0);
dpProps_->dp_F_.rx() = dfn;
}
}
//Compute energies if energy tracking has been enabled.
if (state->trackEnergy_) {
assert(energies_);
energies_->estrain_ = 0.0;
if (kn_)
// Calculate the strain energy.
energies_->estrain_ = 0.5*lin_F_.x()*lin_F_.x()/kn_;
if (ks_) {
DVect s = lin_F_;
s.rx() = 0.0;
double smag2 = s.mag2();
// Add the shear component of the strain energy.
energies_->estrain_ += 0.5*smag2 / ks_;
if (lin_S_) {
// If sliding calculate the slip energy and accumulate it.
lin_F_old.rx() = 0.0;
DVect avg_F_s = (s + lin_F_old)*0.5;
DVect u_s_el = (s - lin_F_old) / ks_;
DVect u_s(0.0);
for (int i=1; i<dim; ++i)
u_s.rdof(i) = trans.dof(i);
energies_->eslip_ -= std::min(0.0,(avg_F_s | (u_s + u_s_el)));
}
}
// Add the rolling resistance energy contributions.
energies_->errstrain_ = 0.0;
if (kr_) {
energies_->errstrain_ = 0.5*res_M_.mag2() / kr_;
if (res_S_) {
// If sliding calculate the slip energy and accumulate it.
DAVect avg_M = (res_M_ + res_M_old)*0.5;
DAVect t_s_el = (res_M_ - res_M_old) / kr_;
energies_->errslip_ -= std::min(0.0,(avg_M | (ang + t_s_el)));
}
}
if (dpProps_) {
// Calculate damping energy (accumulated) if the dashpots are active.
energies_->edashpot_ -= dpProps_->dp_F_ | trans;
}
}
// This is just a sanity check to ensure, in debug mode, that the force isn't wonky.
assert(lin_F_ == lin_F_);
return true;
}
void ContactModelRRLinear::setForce(const DVect &v,IContact *c) {
lin_F(v);
if (v.x() > 0)
rgap_ = c->getGap() + v.x() / kn_;
}
void ContactModelRRLinear::propagateStateInformation(IContactModelMechanical* old,const CAxes &oldSystem,const CAxes &newSystem) {
// Only called for contacts with wall facets when the wall resolution scheme
// is set to full!
// Only do something if the contact model is of the same type
if (old->getContactModel()->getName().compare("rrlinear",Qt::CaseInsensitive) == 0 && !isBonded()) {
ContactModelRRLinear *oldCm = (ContactModelRRLinear *)old;
#ifdef THREED
// Need to rotate just the shear component from oldSystem to newSystem
// Step 1 - rotate oldSystem so that the normal is the same as the normal of newSystem
DVect axis = oldSystem.e1() & newSystem.e1();
double c, ang, s;
DVect re2;
if (!checktol(axis.abs().maxComp(),0.0,1.0,1000)) {
axis = axis.unit();
c = oldSystem.e1()|newSystem.e1();
if (c > 0)
c = std::min(c,1.0);
else
c = std::max(c,-1.0);
ang = acos(c);
s = sin(ang);
double t = 1. - c;
DMatrix<3,3> rm;
rm.get(0,0) = t*axis.x()*axis.x() + c;
rm.get(0,1) = t*axis.x()*axis.y() - axis.z()*s;
rm.get(0,2) = t*axis.x()*axis.z() + axis.y()*s;
rm.get(1,0) = t*axis.x()*axis.y() + axis.z()*s;
rm.get(1,1) = t*axis.y()*axis.y() + c;
rm.get(1,2) = t*axis.y()*axis.z() - axis.x()*s;
rm.get(2,0) = t*axis.x()*axis.z() - axis.y()*s;
rm.get(2,1) = t*axis.y()*axis.z() + axis.x()*s;
rm.get(2,2) = t*axis.z()*axis.z() + c;
re2 = rm*oldSystem.e2();
}
else
re2 = oldSystem.e2();
// Step 2 - get the angle between the oldSystem rotated shear and newSystem shear
axis = re2 & newSystem.e2();
DVect2 tpf;
DVect2 tpm;
DMatrix<2,2> m;
if (!checktol(axis.abs().maxComp(),0.0,1.0,1000)) {
axis = axis.unit();
c = re2|newSystem.e2();
if (c > 0)
c = std::min(c,1.0);
else
c = std::max(c,-1.0);
ang = acos(c);
if (!checktol(axis.x(),newSystem.e1().x(),1.0,100))
ang *= -1;
s = sin(ang);
m.get(0,0) = c;
m.get(1,0) = s;
m.get(0,1) = -m.get(1,0);
m.get(1,1) = m.get(0,0);
tpf = m*DVect2(oldCm->lin_F_.y(),oldCm->lin_F_.z());
tpm = m*DVect2(oldCm->res_M_.y(),oldCm->res_M_.z());
} else {
m.get(0,0) = 1.;
m.get(0,1) = 0.;
m.get(1,0) = 0.;
m.get(1,1) = 1.;
tpf = DVect2(oldCm->lin_F_.y(),oldCm->lin_F_.z());
tpm = DVect2(oldCm->res_M_.y(),oldCm->res_M_.z());
}
DVect pforce = DVect(0,tpf.x(),tpf.y());
DVect pm = DVect(0,tpm.x(),tpm.y());
#else
oldSystem;
newSystem;
DVect pforce = DVect(0,oldCm->lin_F_.y());
DVect pm = DVect(0,oldCm->res_M_.y());
#endif
for (int i=1; i<dim; ++i)
lin_F_.rdof(i) += pforce.dof(i);
oldCm->lin_F_ = DVect(0.0);
oldCm->res_M_ = DAVect(0.0);
if (dpProps_ && oldCm->dpProps_) {
#ifdef THREED
tpf = m*DVect2(oldCm->dpProps_->dp_F_.y(),oldCm->dpProps_->dp_F_.z());
pforce = DVect(oldCm->dpProps_->dp_F_.x(),tpf.x(),tpf.y());
#else
pforce = oldCm->dpProps_->dp_F_;
#endif
dpProps_->dp_F_ += pforce;
oldCm->dpProps_->dp_F_ = DVect(0.0);
}
if(oldCm->getEnergyActivated()) {
activateEnergy();
energies_->estrain_ = oldCm->energies_->estrain_;
energies_->edashpot_ = oldCm->energies_->edashpot_;
energies_->eslip_ = oldCm->energies_->eslip_;
oldCm->energies_->estrain_ = 0.0;
oldCm->energies_->edashpot_ = 0.0;
oldCm->energies_->eslip_ = 0.0;
}
}
assert(lin_F_ == lin_F_);
}
void ContactModelRRLinear::setNonForcePropsFrom(IContactModel *old) {
// Only called for contacts with wall facets when the wall resolution scheme
// is set to full!
// Only do something if the contact model is of the same type
if (old->getName().compare("rrlinear",Qt::CaseInsensitive) == 0 && !isBonded()) {
ContactModelRRLinear *oldCm = (ContactModelRRLinear *)old;
kn_ = oldCm->kn_;
ks_ = oldCm->ks_;
fric_ = oldCm->fric_;
lin_mode_ = oldCm->lin_mode_;
rgap_ = oldCm->rgap_;
res_fric_ = oldCm->res_fric_;
res_S_ = oldCm->res_S_;
kr_ = oldCm->kr_;
fr_ = oldCm->fr_;
userArea_ = oldCm->userArea_;
if (oldCm->dpProps_) {
if (!dpProps_)
dpProps_ = NEWC(dpProps());
dpProps_->dp_nratio_ = oldCm->dpProps_->dp_nratio_;
dpProps_->dp_sratio_ = oldCm->dpProps_->dp_sratio_;
dpProps_->dp_mode_ = oldCm->dpProps_->dp_mode_;
}
}
}
DVect ContactModelRRLinear::getForce(const IContactMechanical *) const {
DVect ret(lin_F_);
if (dpProps_)
ret += dpProps_->dp_F_;
return ret;
}
DAVect ContactModelRRLinear::getMomentOn1(const IContactMechanical *c) const {
DVect force = getForce(c);
DAVect ret(res_M_);
c->updateResultingTorqueOn1Local(force,&ret);
return ret;
}
DAVect ContactModelRRLinear::getMomentOn2(const IContactMechanical *c) const {
DVect force = getForce(c);
DAVect ret(res_M_);
c->updateResultingTorqueOn2Local(force,&ret);
return ret;
}
void ContactModelRRLinear::setDampCoefficients(const double &mass,double *vcn,double *vcs) {
*vcn = dpProps_->dp_nratio_ * 2.0 * sqrt(mass*(kn_));
*vcs = dpProps_->dp_sratio_ * 2.0 * sqrt(mass*(ks_));
}
} // namespace cmodelsxd
// EoF
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