Adhesive Rolling Resistance Linear Model

See this page for the documentation of this contact model.

contactmodelarrlinear.h

  1#pragma once
  2// contactmodelARRLinear.h
  3
  4#include "contactmodel/src/contactmodelmechanical.h"
  5
  6#ifdef ARRLINEAR_LIB
  7#  define ARRLINEAR_EXPORT EXPORT_TAG
  8#elif defined(NO_MODEL_IMPORT)
  9#  define ARRLINEAR_EXPORT
 10#else
 11#  define ARRLINEAR_EXPORT IMPORT_TAG
 12#endif
 13
 14namespace cmodelsxd {
 15    using namespace itasca;
 16
 17    class ContactModelARRLinear : public ContactModelMechanical {
 18    public:
 19        // Constructor: Set default values for contact model properties.
 20        ARRLINEAR_EXPORT ContactModelARRLinear();
 21        ARRLINEAR_EXPORT ContactModelARRLinear(const ContactModelARRLinear &) noexcept;
 22        ARRLINEAR_EXPORT const ContactModelARRLinear & operator=(const ContactModelARRLinear &);
 23        ARRLINEAR_EXPORT void   addToStorage(poly::vector<ContactModelMechanical> *s,int ww = -1) override;
 24        // Destructor, called when contact is deleted: free allocated memory, etc.
 25        ARRLINEAR_EXPORT virtual ~ContactModelARRLinear();
 26        // Contact model name (used as keyword for commands and FISH).
 27        QString  getName() const override { return "arrlinear"; }
 28        // The index provides a quick way to determine the type of contact model.
 29        // Each type of contact model in PFC must have a unique index; this is assigned
 30        // by PFC when the contact model is loaded. This index should be set to -1
 31        void     setIndex(int i) override { index_=i;}
 32        int      getIndex() const  override {return index_;}
 33        // Contact model version number (e.g., MyModel05_1). The version number can be
 34        // accessed during the save-restore operation (within the archive method,
 35        // testing {stream.getRestoreVersion() == getMinorVersion()} to allow for 
 36        // future modifications to the contact model data structure.
 37        uint32   getMinorVersion() const  override;
 38        // Copy the state information to a newly created contact model.
 39        // Provide access to state information, for use by copy method.
 40        void     copy(const ContactModel *c) override;
 41        // Provide save-restore capability for the state information.
 42        void     archive(ArchiveStream &) override;
 43        // Enumerator for the properties.
 44        enum PropertyKeys { 
 45              kwKn=1
 46            , kwKs                            
 47            , kwFric   
 48            , kwLinF
 49            , kwLinS
 50            , kwLinMode
 51            , kwRGap
 52            , kwEmod
 53            , kwKRatio
 54            , kwDpNRatio 
 55            , kwDpSRatio
 56            , kwDpMode 
 57            , kwDpF
 58            , kwResFric
 59            , kwResMoment
 60            , kwResS
 61            , kwResKr
 62            , kwAdhesiveF0
 63            , kwAdhesiveD0
 64            , kwAdhesiveF
 65            , kwUserArea
 66        };
 67        // Contact model property names in a comma separated list. The order corresponds with
 68        // the order of the PropertyKeys enumerator above. One can visualize any of these 
 69        // properties in PFC automatically. 
 70        QString  getProperties() const override {
 71            return "kn"
 72                   ",ks"
 73                   ",fric"
 74                   ",lin_force"
 75                   ",lin_slip"
 76                   ",lin_mode"
 77                   ",rgap"
 78                   ",emod"
 79                   ",kratio"
 80                   ",dp_nratio"
 81                   ",dp_sratio"
 82                   ",dp_mode"
 83                   ",dp_force"
 84                   ",rr_fric"
 85                   ",rr_moment"
 86                   ",rr_slip"
 87                   ",rr_kr"
 88                   ",adh_f0"
 89                   ",adh_d0"
 90                   ",adh_force"
 91                   ",user_area";
 92        }
 93        // Enumerator for the energies.
 94        enum EnergyKeys { 
 95            kwEStrain=1
 96          , kwERRStrain
 97          , kwESlip
 98          , kwERRSlip
 99          , kwEDashpot
100          , kwEAdhesive
101        };
102        // Contact model energy names in a comma separated list. The order corresponds with
103        // the order of the EnergyKeys enumerator above. 
104        QString  getEnergies() const override {
105            return " energy-strain"
106                   ",energy-rrstrain"
107                   ",energy-slip"
108                   ",energy-rrslip"
109                   ",energy-dashpot"
110                   ",energy-adhesive";
111        }
112        // Returns the value of the energy (base 1 - getEnergy(1) returns the estrain energy).
113        double   getEnergy(uint32 i) const override;
114        // Returns whether or not each energy is accumulated (base 1 - getEnergyAccumulate(1) 
115        // returns whether or not the estrain energy is accumulated which is false).
116        bool     getEnergyAccumulate(uint32 i) const override;
117        // Set an energy value (base 1 - setEnergy(1) sets the estrain energy).
118        void     setEnergy(uint32 i,const double &d) override; // Base 1
119        // Activate the energy. This is only called if the energy tracking is enabled. 
120        void     activateEnergy()  override { if (energies_) return; energies_ = NEW Energies();}
121        // Returns whether or not the energy tracking has been enabled for this contact.
122        bool     getEnergyActivated() const  override {return (energies_ != 0);}
123
124        // Enumerator for contact model related FISH callback events. 
125        enum FishCallEvents {
126            fActivated=0
127            ,fSlipChange
128        };
129        // Contact model FISH callback event names in a comma separated list. The order corresponds with
130        // the order of the FishCallEvents enumerator above. 
131        QString  getFishCallEvents() const override {
132            return 
133                "contact_activated"
134                ",slip_change"; 
135        }
136
137        // Return the specified contact model property.
138        QVariant getProperty(uint32 i,const IContact *) const;
139        // The return value denotes whether or not the property corresponds to the global
140        // or local coordinate system (TRUE: global system, FALSE: local system). The
141        // local system is the contact-plane system (nst) defined as follows.
142        // If a vector V is expressed in the local system as (Vn, Vs, Vt), then V is
143        // expressed in the global system as {Vn*nc + Vs*sc + Vt*tc} where where nc, sc
144        // and tc are unit vectors in directions of the nst axes.
145        // This is used when rendering contact model properties that are vectors.
146        bool     getPropertyGlobal(uint32 i) const override;
147        // Set the specified contact model property, ensuring that it is of the correct type
148        // and within the correct range --- if not, then throw an exception.
149        // The return value denotes whether or not the update has affected the timestep
150        // computation (by having modified the translational or rotational tangent stiffnesses).
151        // If true is returned, then the timestep will be recomputed.
152        bool     setProperty(uint32 i,const QVariant &v,IContact *) override;
153        // The return value denotes whether or not the property is read-only
154        // (TRUE: read-only, FALSE: read-write).
155        bool     getPropertyReadOnly(uint32 i) const override;
156
157        // The return value denotes whether or not the property is inheritable
158        // (TRUE: inheritable, FALSE: not inheritable). Inheritance is provided by
159        // the endPropertyUpdated method.
160        bool     supportsInheritance(uint32 i) const override;
161        // Return whether or not inheritance is enabled for the specified property.
162        bool     getInheritance(uint32 i) const override { assert(i<32); uint32 mask = to<uint32>(1 << i);  return (inheritanceField_ & mask) ? true : false; }
163        // Set the inheritance flag for the specified property.
164        void     setInheritance(uint32 i,bool b) override { assert(i<32); uint32 mask = to<uint32>(1 << i);  if (b) inheritanceField_ |= mask;  else inheritanceField_ &= ~mask; }
165
166        // Enumerator for contact model methods.
167        enum MethodKeys { kwDeformability=1, kwArea};
168        // Contact model methoid names in a comma separated list. The order corresponds with
169        // the order of the MethodKeys enumerator above.  
170        QString  getMethods() const override { return "deformability,area";}
171        // Return a comma seprated list of the contact model method arguments (base 1).
172        QString  getMethodArguments(uint32 i) const override;
173        // Set contact model method arguments (base 1). 
174        // The return value denotes whether or not the update has affected the timestep
175        // computation (by having modified the translational or rotational tangent stiffnesses).
176        // If true is returned, then the timestep will be recomputed.
177        bool     setMethod(uint32 i,const QVector<QVariant> &vl,IContact *con=0) override;
178
179        // Prepare for entry into ForceDispLaw. The validate function is called when:
180        // (1) the contact is created, (2) a property of the contact that returns a true via
181        // the setProperty method has been modified and (3) when a set of cycles is executed
182        // via the {cycle N} command.
183        // Return value indicates contact activity (TRUE: active, FALSE: inactive).
184        bool    validate(ContactModelMechanicalState *state,const double &timestep) override;
185        // The endPropertyUpdated method is called whenever a surface property (with a name
186        // that matches an inheritable contact model property name) of one of the contacting
187        // pieces is modified. This allows the contact model to update its associated
188        // properties. The return value denotes whether or not the update has affected
189        // the time step computation (by having modified the translational or rotational
190        // tangent stiffnesses). If true is returned, then the time step will be recomputed.  
191        bool    endPropertyUpdated(const QString &name,const IContactMechanical *c) override;
192        // The forceDisplacementLaw function is called during each cycle. Given the relative
193        // motion of the two contacting pieces (via
194        //   state->relativeTranslationalIncrement_ (Ddn, Ddss, Ddst)
195        //   state->relativeAngularIncrement_       (Dtt, Dtbs, Dtbt)
196        //     Ddn  : relative normal-displacement increment, Ddn > 0 is opening
197        //     Ddss : relative  shear-displacement increment (s-axis component)
198        //     Ddst : relative  shear-displacement increment (t-axis component)
199        //     Dtt  : relative twist-rotation increment
200        //     Dtbs : relative  bend-rotation increment (s-axis component)
201        //     Dtbt : relative  bend-rotation increment (t-axis component)
202        //       The relative displacement and rotation increments:
203        //         Dd = Ddn*nc + Ddss*sc + Ddst*tc
204        //         Dt = Dtt*nc + Dtbs*sc + Dtbt*tc
205        //       where nc, sc and tc are unit vectors in direc. of the nst axes, respectively.
206        //       [see {Table 1: Contact State Variables} in PFC Model Components:
207        //       Contacts and Contact Models: Contact Resolution]
208        // ) and the contact properties, this function must update the contact force and
209        // moment.
210        //   The force_ is acting on piece 2, and is expressed in the local coordinate system
211        //   (defined in getPropertyGlobal) such that the first component positive denotes
212        //   compression. If we define the moment acting on piece 2 by Mc, and Mc is expressed
213        //   in the local coordinate system (defined in getPropertyGlobal), then we must use the getMechanicalContact()->updateResultingTorquesLocal(...) method to 
214        // get the total moment. 
215        // The return value indicates the contact activity status (TRUE: active, FALSE:
216        // inactive) during the next cycle.
217        // Additional information:
218        //   * If state->activated() is true, then the contact has just become active (it was
219        //     inactive during the previous time step).
220        //   * Fully elastic behavior is enforced during the SOLVE ELASTIC command by having
221        //     the forceDispLaw handle the case of {state->canFail_ == true}.
222        bool    forceDisplacementLaw(ContactModelMechanicalState *state,const double &timestep) override;
223        bool    thermalCoupling(ContactModelMechanicalState*, ContactModelThermalState*, IContactThermal*, const double&) override;
224        // The getEffectiveXStiffness functions return the translational and rotational
225        // tangent stiffnesses used to compute a stable time step. When a contact is sliding,
226        // the translational tangent shear stiffness is zero (but this stiffness reduction
227        // is typically ignored when computing a stable time step). If the contact model
228        // includes a dashpot, then the translational stiffnesses must be increased (see
229        // Potyondy (2009)).
230        //   [Potyondy, D. 'Stiffness Matrix at a Contact Between Two Clumps,' Itasca
231        //   Consulting Group, Inc., Minneapolis, MN, Technical Memorandum ICG6863-L,
232        //   December 7, 2009.]
233        DVect2  getEffectiveTranslationalStiffness() const override { return effectiveTranslationalStiffness_; }
234        DAVect  getEffectiveRotationalStiffness() const override { return effectiveRotationalStiffness_;}
235
236        // Return a new instance of the contact model. This is used in the CMAT
237        // when a new contact is created. 
238        ContactModelARRLinear *clone() const override { return NEW ContactModelARRLinear(); }
239        // The getActivityDistance function is called by the contact-resolution logic when
240        // the CMAT is modified. Return value is the activity distance used by the
241        // checkActivity function.
242        double              getActivityDistance() const override {return (rgap_ + a_d0_);}
243        // The isOKToDelete function is called by the contact-resolution logic when...
244        // Return value indicates whether or not the contact may be deleted.
245        // If TRUE, then the contact may be deleted when it is inactive.
246        // If FALSE, then the contact may not be deleted (under any condition).
247        bool                isOKToDelete() const override { return !isBonded(); }
248        // Zero the forces and moments stored in the contact model. This function is called
249        // when the contact becomes inactive.
250        void                resetForcesAndMoments() override { lin_F(DVect(0.0)); dp_F(DVect(0.0));
251                                                              res_M(DAVect(0.0)); a_F(0.0);
252                                                              if (energies_) { energies_->estrain_   = 0.0;
253                                                                               energies_->errstrain_ = 0.0; }
254                                                            }
255        void     setForce(const DVect &v,IContact *c) override;
256        void     setArea(const double &d) override { userArea_ = d; }
257        double   getArea() const override { return userArea_; }
258        // The checkActivity function is called by the contact-resolution logic when...
259        // Return value indicates contact activity (TRUE: active, FALSE: inactive).
260        // A contact with the arrlinear model is active if the surface gap is less than
261        // or equal to the attraction range (a_d0_).
262        bool     checkActivity(const double &gap) override { return  gap <= (rgap_ + a_d0_); }
263
264        // Returns the sliding state (FALSE is returned if not implemented).
265        bool     isSliding() const override { return lin_S_; }
266        // Returns the bonding state (FALSE is returned if not implemented).
267        bool     isBonded() const override { return false; }
268
269        // Both of these methods are called only for contacts with facets where the wall 
270        // resolution scheme is set the full. In such cases one might wish to propagate 
271        // contact state information (e.g., shear force) from one active contact to another. 
272        // See the Faceted Wall section in the documentation. 
273        void     propagateStateInformation(IContactModelMechanical* oldCm,const CAxes &oldSystem=CAxes(),const CAxes &newSystem=CAxes()) override;
274        void     setNonForcePropsFrom(IContactModel *oldCM) override;
275
276        /// Return the total force that the contact model holds.
277        DVect    getForce() const override;
278
279        /// Return the total moment on 1 that the contact model holds
280        DAVect   getMomentOn1(const IContactMechanical *) const override;
281
282        /// Return the total moment on 1 that the contact model holds
283        DAVect   getMomentOn2(const IContactMechanical *) const override;
284        /// Return moments without torque
285        DAVect getModelMomentOn1() const override;
286        DAVect getModelMomentOn2() const override;
287        
288        // Used to efficiently get properties from the contact model for the object pane.
289        // List of properties for the object pane, comma separated.
290        // All properties will be cast to doubles for comparison. No other comparisons
291        // are supported. This may not be the same as the entire property list.
292        // Return property name and type for plotting.
293        void objectPropsTypes(std::vector<std::pair<QString,InfoTypes>> *) const override;
294        // All properties cast to doubles - this is what can be compared. 
295        void objectPropValues(std::vector<double> *,const IContact *) const override;
296   
297        // Methods to get and set properties. 
298        const double & kn() const {return kn_;}
299        void           kn(const double &d) {kn_=d;}
300        const double & ks() const {return ks_;}
301        void           ks(const double &d) {ks_=d;}
302        const double & fric() const {return fric_;}
303        void           fric(const double &d) {fric_=d;}
304        const DVect &  lin_F() const {return lin_F_;}
305        void           lin_F(const DVect &f) { lin_F_=f;}
306        bool           lin_S() const {return lin_S_;}
307        void           lin_S(bool b) { lin_S_=b;}
308        uint32           lin_mode() const {return lin_mode_;}
309        void           lin_mode(uint32 i) { lin_mode_= i;}
310        const double & rgap() const {return rgap_;}
311        void           rgap(const double &d) {rgap_=d;}
312        double         emod(const IContact *c) const;
313        double         kratio() const;
314
315        bool     hasDamping() const {return dpProps_ ? true : false;}
316        double   dp_nratio() const {return (hasDamping() ? (dpProps_->dp_nratio_) : 0.0);}
317        void     dp_nratio(const double &d) { if(!hasDamping()) return; dpProps_->dp_nratio_=d;}
318        double   dp_sratio() const {return hasDamping() ? dpProps_->dp_sratio_: 0.0;}
319        void     dp_sratio(const double &d) { if(!hasDamping()) return; dpProps_->dp_sratio_=d;}
320        int      dp_mode() const {return hasDamping() ? dpProps_->dp_mode_: -1;}
321        void     dp_mode(int i) { if(!hasDamping()) return; dpProps_->dp_mode_=i;}
322        DVect    dp_F() const {return hasDamping() ? dpProps_->dp_F_: DVect(0.0);}
323        void     dp_F(const DVect &f) { if(!hasDamping()) return; dpProps_->dp_F_=f;}
324
325        bool    hasEnergies() const {return energies_ ? true:false;}
326        double  estrain() const {return hasEnergies() ? energies_->estrain_: 0.0;}
327        void    estrain(const double &d) { if(!hasEnergies()) return; energies_->estrain_=d;}
328        double  errstrain() const {return hasEnergies() ? energies_->errstrain_: 0.0;}
329        void    errstrain(const double &d) { if(!hasEnergies()) return; energies_->errstrain_=d;}
330        double  eslip() const {return hasEnergies() ? energies_->eslip_: 0.0;}
331        void    eslip(const double &d) { if(!hasEnergies()) return; energies_->eslip_=d;}
332        double  errslip() const {return hasEnergies() ? energies_->errslip_: 0.0;}
333        void    errslip(const double &d) { if(!hasEnergies()) return; energies_->errslip_=d;}
334        double  edashpot() const {return hasEnergies() ? energies_->edashpot_: 0.0;}
335        void    edashpot(const double &d) { if(!hasEnergies()) return; energies_->edashpot_=d;}
336        double  eadhesive() const {return hasEnergies() ? energies_->eadhesive_: 0.0;}
337        void    eadhesive(const double &d) { if(!hasEnergies()) return; energies_->eadhesive_=d;}
338
339        uint32 inheritanceField() const {return inheritanceField_;}
340        void inheritanceField(uint32 i) {inheritanceField_ = i;}
341
342        const DVect2 & effectiveTranslationalStiffness()  const          {return effectiveTranslationalStiffness_;}
343        void           effectiveTranslationalStiffness(const DVect2 &v ) {effectiveTranslationalStiffness_=v;}
344        const DAVect & effectiveRotationalStiffness()  const             {return effectiveRotationalStiffness_;}
345        void           effectiveRotationalStiffness(const DAVect &v )    {effectiveRotationalStiffness_=v;}
346
347        // Rolling resistance methods
348        const double & res_fric() const {return res_fric_;}
349        void           res_fric(const double &d) {res_fric_=d;}
350        const DAVect & res_M() const               {return res_M_;}
351        void           res_M(const DAVect &f)       { res_M_=f;}
352        bool           res_S() const {return res_S_;}
353        void           res_S(bool b) { res_S_=b;}
354        const double & kr() const {return kr_;}
355        void           kr(const double &d) {kr_=d;}
356        const double & fr() const {return fr_;}
357        void           fr(const double &d) {fr_=d;}
358
359        // Adhesive methods
360        const double & a_f0() const {return   a_f0_;}
361        void           a_f0(const double &d) {a_f0_ = d;}
362        const double & a_d0() const {return   a_d0_;}
363        void           a_d0(const double &d) {a_d0_ = d;}
364        const double & a_F() const {return    a_F_;}
365        void           a_F(const double &d)  {a_F_  = d;}
366
367    private:
368        // Index - used internally by PFC. Should be set to -1 in the cpp file. 
369        static int index_;
370
371        // Structure to store the energies. 
372        struct Energies {
373            Energies() : estrain_(0.0), errstrain_(0.0), eslip_(0.0), errslip_(0.0), edashpot_(0.0), eadhesive_(0.0) {}
374            double estrain_;   // elastic energy stored in linear group 
375            double errstrain_; // elastic energy stored in rolling resistance group
376            double eslip_;     // work dissipated by friction 
377            double errslip_;   // work dissipated by rolling resistance friction 
378            double edashpot_;  // work dissipated by dashpots
379            double eadhesive_; // work done by attractive force on contacting pieces (positive or negative)
380        };
381
382        // Structure to store dashpot quantities. 
383        struct dpProps {
384            dpProps() : dp_nratio_(0.0), dp_sratio_(0.0), dp_mode_(0), dp_F_(DVect(0.0)) {}
385            double dp_nratio_;     // normal viscous critical damping ratio
386            double dp_sratio_;     // shear  viscous critical damping ratio
387            int    dp_mode_;      // for viscous mode (0-4) 0 = dashpots, 1 = tensile limit, 2 = shear limit, 3 = limit both
388            DVect  dp_F_;  // Force in the dashpots
389        };
390
391        bool   updateKn(const IContactMechanical *con);
392        bool   updateKs(const IContactMechanical *con);
393        bool   updateFric(const IContactMechanical *con);
394        bool   updateResFric(const IContactMechanical *con);
395
396        void   updateStiffness(ContactModelMechanicalState *state);
397
398        void   setDampCoefficients(const double &mass,double *vcn,double *vcs);
399
400        // Contact model inheritance fields.
401        uint32 inheritanceField_;
402
403        // Effective translational stiffness.
404        DVect2  effectiveTranslationalStiffness_ = DVect2(0.0);
405        DAVect  effectiveRotationalStiffness_ = DAVect(0.0);      // (Twisting,Bending,Bending) Rotational stiffness (twisting always 0)
406
407        // linear model properties
408        double      kn_ = 0.0;        // Normal stiffness
409        double      ks_ = 0.0;        // Shear stiffness
410        double      fric_ = 0.0;      // Coulomb friction coefficient
411        DVect       lin_F_ = DVect(0.0);     // Force carried in the linear model
412        bool        lin_S_ = false;     // The current slip state
413        uint32      lin_mode_ = 0;  // Specifies absolute (0) or incremental (1) calculation mode 
414        double      rgap_ = 0;      // Reference gap 
415        dpProps *   dpProps_ = nullptr;   // The viscous properties
416
417        // rolling resistance properties
418        double res_fric_ = 0.0;       // rolling friction coefficient
419        DAVect res_M_ = DAVect(0.0);          // moment (bending only)         
420        bool   res_S_ = false;          // The current rolling resistance slip state
421        double kr_ = 0.0;             // bending rotational stiffness (read-only, calculated internaly) 
422        double fr_ = 0.0;             // rolling friction coefficient (rbar*res_fric_) (calculated internaly, not a property)
423
424        // Adhesive properties
425        double a_f0_ = 0.0;  // maximum attractive force [force], "a_f0"
426        double a_d0_ = 0.0;  // attraction range [length]       , "a_d0"
427        double a_F_ = 0.0;   // attractive force [force]        , "a_force"
428        double      userArea_ = 0.0;   // Area as specified by the user 
429        Energies *   energies_ = nullptr; // The energies
430
431    };
432} // namespace cmodelsxd
433// EoF

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contactmodelarrlinear.cpp

   1// contactmodelARRLinear.cpp
   2#include "contactmodelarrlinear.h"
   3
   4#include "module/interface/icontactmechanical.h"
   5#include "module/interface/icontact.h"
   6#include "module/interface/ipiece.h"
   7#include "module/interface/ifishcalllist.h"
   8
   9#include "shared/src/mathutil.h"
  10
  11#include "kernel/interface/iprogram.h"
  12#include "module/interface/icontactthermal.h"
  13#include "contactmodel/src/contactmodelthermal.h"
  14#include "../version.txt"
  15#include "fish/src/parameter.h"
  16
  17#ifdef ARRLINEAR_LIB
  18#ifdef _WIN32
  19    int __stdcall DllMain(void *,unsigned, void *) {
  20        return 1;
  21    }
  22#endif
  23
  24    extern "C" EXPORT_TAG const char *getName() {
  25#if DIM==3
  26        return "contactmodelmechanical3dARRLinear";
  27#else
  28        return "contactmodelmechanical2dARRLinear";
  29#endif
  30    }
  31
  32    extern "C" EXPORT_TAG unsigned getMajorVersion() {
  33        return MAJOR_VERSION;
  34    }
  35
  36    extern "C" EXPORT_TAG unsigned getMinorVersion() {
  37        return MINOR_VERSION; ;
  38    }
  39
  40    extern "C" EXPORT_TAG void *createInstance() {
  41        cmodelsxd::ContactModelARRLinear *m = NEW cmodelsxd::ContactModelARRLinear();
  42        return (void *)m;
  43    }
  44#endif
  45
  46namespace cmodelsxd {
  47    static const uint32 linKnMask      = 0x00000002; // Base 1!
  48    static const uint32 linKsMask      = 0x00000004;
  49    static const uint32 linFricMask    = 0x00000008;
  50    static const uint32 resFricMask    = 0x00004000;
  51
  52    using namespace itasca;
  53
  54    int ContactModelARRLinear::index_ = -1;
  55    uint32 ContactModelARRLinear::getMinorVersion() const { return MINOR_VERSION; }
  56
  57    ContactModelARRLinear::ContactModelARRLinear() : inheritanceField_(linKnMask|linKsMask|linFricMask|resFricMask)
  58    { }
  59    
  60    ContactModelARRLinear::ContactModelARRLinear(const ContactModelARRLinear &m) noexcept {
  61        inheritanceField_ = linKnMask|linKsMask|linFricMask|resFricMask;
  62        this->copy(&m);
  63    }
  64    
  65    const ContactModelARRLinear & ContactModelARRLinear::operator=(const ContactModelARRLinear &m) {
  66        inheritanceField_ = linKnMask|linKsMask|linFricMask|resFricMask;
  67        this->copy(&m);
  68        return *this;
  69    }
  70    
  71    void ContactModelARRLinear::addToStorage(poly::vector<ContactModelMechanical> *s,int ww) { 
  72        s->addToStorage<ContactModelARRLinear>(*this,ww);
  73    }
  74
  75    ContactModelARRLinear::~ContactModelARRLinear() {
  76        // Make sure to clean up after yourself!
  77        if (dpProps_)
  78            delete dpProps_;
  79        if (energies_)
  80            delete energies_;
  81    }
  82
  83    void ContactModelARRLinear::archive(ArchiveStream &stream) {
  84        // The stream allows one to archive the values of the contact model
  85        // so that it can be saved and restored. The minor version can be
  86        // used here to allow for incremental changes to the contact model too.
  87        stream & kn_;
  88        stream & ks_;
  89        stream & fric_;
  90        stream & lin_F_;
  91        stream & lin_S_;
  92        stream & lin_mode_;
  93        stream & rgap_;
  94        stream & res_fric_;
  95        stream & res_M_;
  96        stream & res_S_;
  97        stream & kr_;
  98        stream & fr_;
  99        stream & a_f0_;
 100        stream & a_d0_;
 101        stream & a_F_;
 102
 103        if (stream.getArchiveState()==ArchiveStream::Save) {
 104            bool b = false;
 105            if (dpProps_) {
 106                b = true;
 107                stream & b;
 108                stream & dpProps_->dp_nratio_;
 109                stream & dpProps_->dp_sratio_;
 110                stream & dpProps_->dp_mode_;
 111                stream & dpProps_->dp_F_;
 112            }
 113            else
 114                stream & b;
 115
 116            b = false;
 117            if (energies_) {
 118                b = true;
 119                stream & b;
 120                stream & energies_->estrain_;
 121                stream & energies_->errstrain_;
 122                stream & energies_->eslip_;
 123                stream & energies_->errslip_;
 124                stream & energies_->edashpot_;
 125                stream & energies_->eadhesive_;
 126            }
 127            else
 128                stream & b;
 129        } else {
 130            bool b(false);
 131            stream & b;
 132            if (b) {
 133                if (!dpProps_)
 134                    dpProps_ = NEW dpProps();
 135                stream & dpProps_->dp_nratio_;
 136                stream & dpProps_->dp_sratio_;
 137                stream & dpProps_->dp_mode_;
 138                stream & dpProps_->dp_F_;
 139            }
 140            stream & b;
 141            if (b) {
 142                if (!energies_)
 143                    energies_ = NEW Energies();
 144                stream & energies_->estrain_;
 145                stream & energies_->errstrain_;
 146                stream & energies_->eslip_;
 147                stream & energies_->errslip_;
 148                stream & energies_->edashpot_;
 149                stream & energies_->eadhesive_;
 150            }
 151        }
 152
 153        stream & inheritanceField_;
 154        stream & effectiveTranslationalStiffness_;
 155        stream & effectiveRotationalStiffness_;
 156
 157        if (stream.getArchiveState()==ArchiveStream::Save || stream.getRestoreVersion() > 1)
 158            stream & userArea_;
 159    }
 160
 161    void ContactModelARRLinear::copy(const ContactModel *cm) {
 162        // Copy all of the contact model properties. Used in the CMAT
 163        // when a new contact is created.
 164        ContactModelMechanical::copy(cm);
 165        const ContactModelARRLinear *in = dynamic_cast<const ContactModelARRLinear*>(cm);
 166        if (!in) throw std::runtime_error("Internal error: contact model dynamic cast failed.");
 167        kn(in->kn());
 168        ks(in->ks());
 169        fric(in->fric());
 170        lin_F(in->lin_F());
 171        lin_S(in->lin_S());
 172        lin_mode(in->lin_mode());
 173        rgap(in->rgap());
 174        res_fric(in->res_fric());
 175        res_M(in->res_M());
 176        res_S(in->res_S());
 177        kr(in->kr());
 178        fr(in->fr());
 179        a_f0(in->a_f0());
 180        a_d0(in->a_d0());
 181        a_F(in->a_F());
 182
 183        if (in->hasDamping()) {
 184            if (!dpProps_)
 185                dpProps_ = NEW dpProps();
 186            dp_nratio(in->dp_nratio());
 187            dp_sratio(in->dp_sratio());
 188            dp_mode(in->dp_mode());
 189            dp_F(in->dp_F());
 190        }
 191        if (in->hasEnergies()) {
 192            if (!energies_)
 193                energies_ = NEW Energies();
 194            estrain(in->estrain());
 195            errstrain(in->errstrain());
 196            eslip(in->eslip());
 197            errslip(in->errslip());
 198            edashpot(in->edashpot());
 199            eadhesive(in->eadhesive());
 200        }
 201        userArea_ = in->userArea_;
 202        inheritanceField(in->inheritanceField());
 203        effectiveTranslationalStiffness(in->effectiveTranslationalStiffness());
 204        effectiveRotationalStiffness(in->effectiveRotationalStiffness());
 205    }
 206
 207
 208    QVariant ContactModelARRLinear::getProperty(uint32 i,const IContact *con) const {
 209        // Return the property. The IContact pointer is provided so that
 210        // more complicated properties, depending on contact characteristics,
 211        // can be calcualted. The IContact pointer may be a nullptr!
 212        const IContactMechanical *c(convert_getcast<IContactMechanical>(con));        
 213        QVariant var;
 214        switch (i) {
 215        case kwKn:        return kn_;
 216        case kwKs:        return ks_;
 217        case kwFric:      return fric_;
 218        case kwLinF:      var.setValue(lin_F_); return var;
 219        case kwLinS:      return lin_S_;
 220        case kwLinMode:   return lin_mode_;
 221        case kwRGap:      return rgap_;
 222        case kwEmod:      return emod(con);
 223        case kwKRatio:    return kratio();
 224        case kwDpNRatio:  return dpProps_ ? dpProps_->dp_nratio_ : 0;
 225        case kwDpSRatio:  return dpProps_ ? dpProps_->dp_sratio_ : 0;
 226        case kwDpMode:    return dpProps_ ? dpProps_->dp_mode_ : 0;
 227        case kwDpF: {
 228                dpProps_ ? var.setValue(dpProps_->dp_F_) : var.setValue(DVect(0.0));
 229                return var;
 230            }
 231        case kwResFric:     return res_fric_;
 232        case kwResMoment:   var.setValue(res_M_); return var;
 233        case kwResS:        return res_S_;
 234        case kwResKr:       return kr_;
 235        case kwAdhesiveF0:  return a_f0_;
 236        case kwAdhesiveD0:  return a_d0_;
 237        case kwAdhesiveF:   return a_F_;
 238        case kwUserArea :   return userArea_;
 239        }
 240        assert(0);
 241        return QVariant();
 242    }
 243
 244    bool ContactModelARRLinear::getPropertyGlobal(uint32 i) const {
 245        // Returns whether or not a property is held in the global axis system (TRUE)
 246        // or the local system (FALSE). Used by the plotting logic.
 247        switch (i) {
 248        case kwLinF:
 249        case kwDpF:
 250        case kwResMoment:
 251            return false;
 252        }
 253        return true;
 254    }
 255
 256    bool ContactModelARRLinear::setProperty(uint32 i,const QVariant &v,IContact *) {
 257        // Set a contact model property. Return value indicates that the timestep
 258        // should be recalculated.
 259        dpProps dp;
 260        switch (i) {
 261        case kwKn: {
 262                if (!v.canConvert<double>())
 263                    throw Exception("kn must be a double.");
 264                double val(v.toDouble());
 265                if (val<0.0)
 266                    throw Exception("Negative kn not allowed.");
 267                kn_ = val;
 268                return true;
 269            }
 270        case kwKs: {
 271                if (!v.canConvert<double>())
 272                    throw Exception("ks must be a double.");
 273                double val(v.toDouble());
 274                if (val<0.0)
 275                    throw Exception("Negative ks not allowed.");
 276                ks_ = val;
 277                return true;
 278            }
 279        case kwFric: {
 280                if (!v.canConvert<double>())
 281                    throw Exception("fric must be a double.");
 282                double val(v.toDouble());
 283                if (val<0.0)
 284                    throw Exception("Negative fric not allowed.");
 285                fric_ = val;
 286                return false;
 287            }
 288        case kwLinF: {
 289                if (!v.canConvert<DVect>())
 290                    throw Exception("lin_force must be a vector.");
 291                DVect val(v.value<DVect>());
 292                lin_F_ = val;
 293                return false;
 294            }
 295        case kwLinMode: {
 296                if (!v.canConvert<uint32>())
 297                    throw Exception("lin_mode must be 0 (absolute) or 1 (incremental).");
 298                uint32 val(v.toUInt());
 299                if (val >1)
 300                    throw Exception("lin_mode must be 0 (absolute) or 1 (incremental).");
 301                lin_mode_ = val;
 302                return false;
 303            }
 304        case kwRGap: {
 305                if (!v.canConvert<double>())
 306                    throw Exception("Reference gap must be a double.");
 307                double val(v.toDouble());
 308                rgap_ = val;
 309                return false;
 310            }
 311        case kwDpNRatio: {
 312                if (!v.canConvert<double>())
 313                    throw Exception("dp_nratio must be a double.");
 314                double val(v.toDouble());
 315                if (val<0.0)
 316                    throw Exception("Negative dp_nratio not allowed.");
 317                if (val == 0.0 && !dpProps_)
 318                    return false;
 319                if (!dpProps_)
 320                    dpProps_ = NEW dpProps();
 321                dpProps_->dp_nratio_ = val;
 322                return true;
 323            }
 324        case kwDpSRatio: {
 325                if (!v.canConvert<double>())
 326                    throw Exception("dp_sratio must be a double.");
 327                double val(v.toDouble());
 328                if (val<0.0)
 329                    throw Exception("Negative dp_sratio not allowed.");
 330                if (val == 0.0 && !dpProps_)
 331                    return false;
 332                if (!dpProps_)
 333                    dpProps_ = NEW dpProps();
 334                dpProps_->dp_sratio_ = val;
 335                return true;
 336            }
 337        case kwDpMode: {
 338                if (!v.canConvert<int>())
 339                    throw Exception("The viscous mode dp_mode must be 0, 1, 2, or 3.");
 340                int val(v.toInt());
 341                if (val == 0 && !dpProps_)
 342                    return false;
 343                if (val < 0 || val > 3)
 344                    throw Exception("The viscous mode dp_mode must be 0, 1, 2, or 3.");
 345                if (!dpProps_)
 346                    dpProps_ = NEW dpProps();
 347                dpProps_->dp_mode_ = val;
 348                return false;
 349            }
 350        case kwDpF: {
 351                if (!v.canConvert<DVect>())
 352                    throw Exception("dp_force must be a vector.");
 353                DVect val(v.value<DVect>());
 354                if (val.fsum() == 0.0 && !dpProps_)
 355                    return false;
 356                if (!dpProps_)
 357                    dpProps_ = NEW dpProps();
 358                dpProps_->dp_F_ = val;
 359                return false;
 360            }
 361        case kwResFric: {
 362                if (!v.canConvert<double>())
 363                    throw Exception("res_fric must be a double.");
 364                double val(v.toDouble());
 365                if (val<0.0)
 366                    throw Exception("Negative res_fric not allowed.");
 367                res_fric_ = val;
 368                return false;
 369            }
 370        case kwResMoment: {
 371                DAVect val(0.0);
 372#ifdef TWOD
 373                if (!v.canConvert<DAVect>() && !v.canConvert<double>())
 374                    throw Exception("res_moment must be an angular vector.");
 375                if (v.canConvert<DAVect>())
 376                    val = DAVect(v.value<DAVect>());
 377                else
 378                    val = DAVect(v.toDouble());
 379#else
 380                if (!v.canConvert<DAVect>() && !v.canConvert<DVect>())
 381                    throw Exception("res_moment must be an angular vector.");
 382                if (v.canConvert<DAVect>())
 383                    val = DAVect(v.value<DAVect>());
 384                else
 385                    val = DAVect(v.value<DVect>());
 386#endif
 387                res_M_ = val;
 388                return false;
 389            }
 390        case kwAdhesiveF0: {
 391                if (!v.canConvert<double>())
 392                    throw Exception("a_f0 must be a double.");
 393                double val(v.toDouble());
 394                if (val<0.0)
 395                    throw Exception("Negative a_f0 not allowed.");
 396                a_f0_ = val;
 397                return true;
 398            }
 399        case kwAdhesiveD0: {
 400                if (!v.canConvert<double>())
 401                    throw Exception("a_d0 must be a double.");
 402                double val(v.toDouble());
 403                if (val<0.0)
 404                    throw Exception("Negative a_d0 not allowed.");
 405                a_d0_ = val;
 406                return true;
 407            }
 408        case kwUserArea: {
 409                if (!v.canConvert<double>())
 410                    throw Exception("user_area must be a double.");
 411                double val(v.toDouble());
 412                if (val < 0.0)
 413                    throw Exception("Negative user_area not allowed.");
 414                userArea_ = val;
 415                return true;
 416            }
 417        }
 418        return false;
 419    }
 420
 421    bool ContactModelARRLinear::getPropertyReadOnly(uint32 i) const {
 422        // Returns TRUE if a property is read only or FALSE otherwise.
 423        switch (i) {
 424        case kwDpF:
 425        case kwLinS:
 426        case kwEmod:
 427        case kwKRatio:
 428        case kwResS:
 429        case kwResKr:
 430        case kwAdhesiveF:
 431            return true;
 432        default:
 433            break;
 434        }
 435        return false;
 436    }
 437
 438    bool ContactModelARRLinear::supportsInheritance(uint32 i) const {
 439        // Returns TRUE if a property supports inheritance or FALSE otherwise.
 440        switch (i) {
 441        case kwKn:
 442        case kwKs:
 443        case kwFric:
 444        case kwResFric:
 445            return true;
 446        default:
 447            break;
 448        }
 449        return false;
 450    }
 451
 452    QString  ContactModelARRLinear::getMethodArguments(uint32 i) const {
 453        // Return a list of contact model method argument names.
 454        switch (i) {
 455        case kwDeformability:
 456            return "emod,kratio";
 457        case kwArea:
 458            return QString();
 459        }
 460        assert(0);
 461        return QString();
 462    }
 463
 464    bool ContactModelARRLinear::setMethod(uint32 i,const QVector<QVariant> &vl,IContact *con) {
 465        // Apply the specified method.
 466        IContactMechanical *c(convert_getcast<IContactMechanical>(con));
 467        switch (i) {
 468        case kwDeformability: {
 469                double emod;
 470                double krat;
 471                if (vl.at(0).isNull())
 472                    throw Exception("Argument emod must be specified with method deformability in contact model {0}.",getName());
 473                emod = vl.at(0).toDouble();
 474                if (emod<0.0)
 475                    throw Exception("Negative emod not allowed in contact model {0}.",getName());
 476                if (vl.at(1).isNull())
 477                    throw Exception("Argument kratio must be specified with method deformability in contact model {0}.",getName());
 478                krat = vl.at(1).toDouble();
 479                if (krat<0.0)
 480                    throw Exception("Negative stiffness ratio not allowed in contact model {0}.",getName());
 481                double rsq(std::max(c->getEnd1Curvature().y(),c->getEnd2Curvature().y()));
 482                double rsum(0.0);
 483                if (c->getEnd1Curvature().y())
 484                    rsum += 1.0/c->getEnd1Curvature().y();
 485                if (c->getEnd2Curvature().y())
 486                    rsum += 1.0/c->getEnd2Curvature().y();
 487                if (userArea_) {
 488#ifdef THREED
 489                    rsq = std::sqrt(userArea_ / dPi);
 490#else
 491                    rsq = userArea_ / 2.0;
 492#endif
 493                    rsum = rsq + rsq;
 494                    rsq = 1. / rsq;
 495                }
 496#ifdef TWOD
 497                kn_ = 2.0 * emod / (rsq * rsum);
 498#else
 499                kn_ = dPi * emod / (rsq * rsq * rsum);
 500#endif
 501                ks_ = (krat == 0.0) ? 0.0 : kn_ / krat;
 502                setInheritance(1,false);
 503                setInheritance(2,false);
 504                return true;
 505            }
 506        case kwArea: {
 507                if (!userArea_) {
 508                    double rsq(1./std::max(c->getEnd1Curvature().y(),c->getEnd2Curvature().y()));
 509#ifdef THREED
 510                    userArea_ = rsq * rsq * dPi;
 511#else
 512                    userArea_ = rsq * 2.0;
 513#endif
 514                }
 515                return true;
 516            }
 517        }
 518        return false;
 519    }
 520
 521    double ContactModelARRLinear::getEnergy(uint32 i) const {
 522        // Return an energy value.
 523        double ret(0.0);
 524        if (!energies_)
 525            return ret;
 526        switch (i) {
 527        case kwEStrain:    return energies_->estrain_;
 528        case kwERRStrain:  return energies_->errstrain_;
 529        case kwESlip:      return energies_->eslip_;
 530        case kwERRSlip:    return energies_->errslip_;
 531        case kwEDashpot:   return energies_->edashpot_;
 532        case kwEAdhesive:  return energies_->eadhesive_;
 533        }
 534        assert(0);
 535        return ret;
 536    }
 537
 538    bool ContactModelARRLinear::getEnergyAccumulate(uint32 i) const {
 539        // Returns TRUE if the corresponding energy is accumulated or FALSE otherwise.
 540        switch (i) {
 541        case kwEStrain:   return false;
 542        case kwERRStrain: return false;
 543        case kwESlip:     return true;
 544        case kwERRSlip:   return true;
 545        case kwEDashpot:  return true;
 546        case kwEAdhesive: return true;
 547        }
 548        assert(0);
 549        return false;
 550    }
 551
 552    void ContactModelARRLinear::setEnergy(uint32 i,const double &d) {
 553        // Set an energy value.
 554        if (!energies_) return;
 555        switch (i) {
 556        case kwEStrain:    energies_->estrain_ = d;   return;
 557        case kwERRStrain:  energies_->errstrain_ = d; return;
 558        case kwESlip:      energies_->eslip_   = d;   return;
 559        case kwERRSlip:    energies_->errslip_   = d; return;
 560        case kwEDashpot:   energies_->edashpot_= d;   return;
 561        case kwEAdhesive:  energies_->eadhesive_= d;  return;
 562        }
 563        assert(0);
 564        return;
 565    }
 566
 567    bool ContactModelARRLinear::validate(ContactModelMechanicalState *state,const double &) {
 568        // Validate the / Prepare for entry into ForceDispLaw. The validate function is called when:
 569        // (1) the contact is created, (2) a property of the contact that returns a true via
 570        // the setProperty method has been modified and (3) when a set of cycles is executed
 571        // via the {cycle N} command.
 572        // Return value indicates contact activity (TRUE: active, FALSE: inactive).
 573        assert(state);
 574        const IContactMechanical *c = state->getMechanicalContact();
 575        assert(c);
 576
 577        if (state->trackEnergy_)
 578            activateEnergy();
 579
 580        if (inheritanceField_ & linKnMask)
 581            updateKn(c);
 582        if (inheritanceField_ & linKsMask)
 583            updateKs(c);
 584        if (inheritanceField_ & linFricMask)
 585            updateFric(c);
 586        if (inheritanceField_ & resFricMask)
 587            updateResFric(c);
 588
 589        updateStiffness(state);
 590        return checkActivity(state->gap_);
 591    }
 592
 593    static const QString knstr("kn");
 594    bool ContactModelARRLinear::updateKn(const IContactMechanical *con) {
 595        assert(con);
 596        QVariant v1 = con->getEnd1()->getProperty(knstr);
 597        QVariant v2 = con->getEnd2()->getProperty(knstr);
 598        if (!v1.isValid() || !v2.isValid())
 599            return false;
 600        double kn1 = v1.toDouble();
 601        double kn2 = v2.toDouble();
 602        double val = kn_;
 603        if (kn1 && kn2)
 604            kn_ = kn1*kn2/(kn1+kn2);
 605        else if (kn1)
 606            kn_ = kn1;
 607        else if (kn2)
 608            kn_ = kn2;
 609        return ( (kn_ != val) );
 610    }
 611
 612    static const QString ksstr("ks");
 613    bool ContactModelARRLinear::updateKs(const IContactMechanical *con) {
 614        assert(con);
 615        QVariant v1 = con->getEnd1()->getProperty(ksstr);
 616        QVariant v2 = con->getEnd2()->getProperty(ksstr);
 617        if (!v1.isValid() || !v2.isValid())
 618            return false;
 619        double ks1 = v1.toDouble();
 620        double ks2 = v2.toDouble();
 621        double val = ks_;
 622        if (ks1 && ks2)
 623            ks_ = ks1*ks2/(ks1+ks2);
 624        else if (ks1)
 625            ks_ = ks1;
 626        else if (ks2)
 627            ks_ = ks2;
 628        return ( (ks_ != val) );
 629    }
 630
 631    static const QString fricstr("fric");
 632    bool ContactModelARRLinear::updateFric(const IContactMechanical *con) {
 633        assert(con);
 634        QVariant v1 = con->getEnd1()->getProperty(fricstr);
 635        QVariant v2 = con->getEnd2()->getProperty(fricstr);
 636        if (!v1.isValid() || !v2.isValid())
 637            return false;
 638        double fric1 = std::max(0.0,v1.toDouble());
 639        double fric2 = std::max(0.0,v2.toDouble());
 640        double val = fric_;
 641        fric_ = std::min(fric1,fric2);
 642        return ( (fric_ != val) );
 643    }
 644
 645    static const QString rfricstr("rr_fric");
 646    bool ContactModelARRLinear::updateResFric(const IContactMechanical *con) {
 647        assert(con);
 648        QVariant v1 = con->getEnd1()->getProperty(rfricstr);
 649        QVariant v2 = con->getEnd2()->getProperty(rfricstr);
 650        if (!v1.isValid() || !v2.isValid())
 651            return false;
 652        double rfric1 = std::max(0.0,v1.toDouble());
 653        double rfric2 = std::max(0.0,v2.toDouble());
 654        double val = res_fric_;
 655        res_fric_ = std::min(rfric1,rfric2);
 656        return ( (res_fric_ != val) );
 657    }
 658
 659    bool ContactModelARRLinear::endPropertyUpdated(const QString &name,const IContactMechanical *c) {
 660        // The endPropertyUpdated method is called whenever a surface property (with a name
 661        // that matches an inheritable contact model property name) of one of the contacting
 662        // pieces is modified. This allows the contact model to update its associated
 663        // properties. The return value denotes whether or not the update has affected
 664        // the time step computation (by having modified the translational or rotational
 665        // tangent stiffnesses). If true is returned, then the time step will be recomputed.
 666        assert(c);
 667        QStringList availableProperties = getProperties().simplified().replace(" ","").split(",",Qt::SkipEmptyParts);
 668        QRegularExpression rx(name, QRegularExpression::CaseInsensitiveOption);
 669        int idx = availableProperties.indexOf(rx)+1;
 670        bool ret=false;
 671
 672        if (idx<=0)
 673            return ret;
 674
 675        switch(idx) {
 676        case kwKn:  { //kn
 677                if (inheritanceField_ & linKnMask)
 678                    ret = updateKn(c);
 679                break;
 680            }
 681        case kwKs:  { //ks
 682                if (inheritanceField_ & linKsMask)
 683                    ret =updateKs(c);
 684                break;
 685            }
 686        case kwFric:  { //fric
 687                if (inheritanceField_ & linFricMask)
 688                    updateFric(c);
 689                break;
 690            }
 691        case kwResFric:  { //rr_fric
 692                if (inheritanceField_ & resFricMask)
 693                   ret = updateResFric(c);
 694                break;
 695            }
 696        }
 697        return ret;
 698    }
 699
 700    void ContactModelARRLinear::updateStiffness(ContactModelMechanicalState *state) {
 701        // first compute rolling resistance stiffness
 702        kr_ = 0.0;
 703        if (res_fric_ > 0.0) {
 704            double rbar = 0.0;
 705            double r1 = 1.0/state->end1Curvature_.y();
 706            rbar = r1;
 707            double r2 = 0.0;
 708            if (state->end2Curvature_.y()) {
 709                r2 = 1.0 / state->end2Curvature_.y();
 710                rbar = (r1*r2) / (r1+r2);
 711            }
 712            if (userArea_) {
 713#ifdef THREED
 714                r1 = std::sqrt(userArea_ / dPi);
 715#else
 716                r1 = userArea_ / 2.0;
 717#endif
 718                r2 = r1;
 719                rbar = (r1*r2) / (r1+r2);
 720            }
 721            kr_ = ks_*rbar*rbar;
 722            fr_ = res_fric_*rbar;
 723        }
 724        // Now calculate effective stiffness
 725        DVect2 retT(kn_,ks_);
 726        // correction if viscous damping active
 727        if (dpProps_) {
 728            DVect2 correct(1.0);
 729            if (dpProps_->dp_nratio_)
 730                correct.rx() = sqrt(1.0+dpProps_->dp_nratio_*dpProps_->dp_nratio_) - dpProps_->dp_nratio_;
 731            if (dpProps_->dp_sratio_)
 732                correct.ry() = sqrt(1.0+dpProps_->dp_sratio_*dpProps_->dp_sratio_) - dpProps_->dp_sratio_;
 733            retT /= (correct*correct);
 734        }
 735        // Correction for adhesive group
 736        if (a_d0_ != 0.0) { retT.rdof(0) += a_f0_ / a_d0_; }
 737
 738        effectiveTranslationalStiffness_ = retT;
 739        // Effective rotational stiffness (bending only)
 740        effectiveRotationalStiffness_ = DAVect(kr_);
 741#if DIM==3
 742        effectiveRotationalStiffness_.rx() = 0.0;
 743#endif
 744    }
 745
 746    bool ContactModelARRLinear::forceDisplacementLaw(ContactModelMechanicalState *state,const double &timestep) {
 747        assert(state);
 748
 749        // Current overlap
 750        double overlap = rgap_ - state->gap_;
 751        // Relative translational increment
 752        DVect trans = state->relativeTranslationalIncrement_;
 753        // Correction factor to account for when the contact becomes newly active.
 754        // We estimate the time of activity during the timestep when the contact has first
 755        // become active and scale the forces accordingly.
 756        double correction = 1.0;
 757
 758        // The contact was just activated from an inactive state
 759        if (state->activated()) {
 760            // Trigger the FISH callback if one is hooked up to the
 761            // contact_activated event.
 762            if (cmEvents_[fActivated] >= 0) {
 763                auto c = state->getContact();
 764                std::vector<fish::Parameter> arg = { fish::Parameter(c->getIThing()) };
 765                IFishCallList *fi = const_cast<IFishCallList*>(state->getProgram()->findInterface<IFishCallList>());
 766                fi->setCMFishCallArguments(c,arg,cmEvents_[fActivated]);
 767            }
 768            // Calculate the correction factor.
 769            if (trans.x()) {
 770                correction = -1.0*overlap / trans.x();
 771                if (correction < 0)
 772                    correction = 1.0;
 773            }
 774        }
 775
 776        // Angular dispacement increment.
 777        DAVect ang  = state->relativeAngularIncrement_;
 778        DVect lin_F_old = lin_F_;
 779
 780        if (lin_mode_ == 0)
 781            lin_F_.rx() = overlap * kn_; // absolute mode for normal force calculation
 782        else
 783          lin_F_.rx() -= correction * trans.x() * kn_; // incremental mode for normal force calculation
 784
 785        // Normal force can only be positive.
 786        lin_F_.rx() = std::max(0.0,lin_F_.x());
 787
 788        // Calculate the shear force.
 789        DVect sforce(0.0);
 790        // dim holds the dimension (e.g., 2 for 2D and 3 for 3D)
 791        // Loop over the shear components (note: the 0 component is the normal component)
 792        // and calculate the shear force.
 793        for (int i=1; i<dim; ++i)
 794            sforce.rdof(i) = lin_F_.dof(i) - trans.dof(i) * ks_ * correction;
 795
 796        // The canFail flag corresponds to whether or not the contact can undergo non-linear
 797        // force-displacement response. If the SOLVE ELASTIC command is given then the
 798        // canFail state is set to FALSE. Otherwise it is always TRUE.
 799        if (state->canFail_) {
 800            // Resolve sliding. This is the normal force multiplied by the coefficient of friction.
 801            double crit = lin_F_.x() * fric_;
 802            // The is the magnitude of the shear force.
 803            double sfmag = sforce.mag();
 804            // Sliding occurs when the magnitude of the shear force is greater than the
 805            // critical value.
 806            if (sfmag > crit) {
 807                // Lower the shear force to the critical value for sliding.
 808                double rat = crit / sfmag;
 809                sforce *= rat;
 810                // Handle the slip_change event if one has been hooked up. Sliding has commenced.
 811                if (!lin_S_ && cmEvents_[fSlipChange] >= 0) {
 812                    auto c = state->getContact();
 813                    std::vector<fish::Parameter> arg = { fish::Parameter(c->getIThing()),
 814                                                         fish::Parameter() };
 815                    IFishCallList *fi = const_cast<IFishCallList*>(state->getProgram()->findInterface<IFishCallList>());
 816                    fi->setCMFishCallArguments(c,arg,cmEvents_[fSlipChange]);
 817                }
 818                lin_S_ = true;
 819            } else {
 820                // Handle the slip_change event if one has been hooked up and
 821                // the contact was previously sliding. Sliding has ceased.
 822                if (lin_S_) {
 823                    if (cmEvents_[fSlipChange] >= 0) {
 824                    auto c = state->getContact();
 825                    std::vector<fish::Parameter> arg = { fish::Parameter(c->getIThing()),
 826                                                         fish::Parameter((qint64)1) };
 827                    IFishCallList *fi = const_cast<IFishCallList*>(state->getProgram()->findInterface<IFishCallList>());
 828                    fi->setCMFishCallArguments(c,arg,cmEvents_[fSlipChange]);
 829                    }
 830                    lin_S_ = false;
 831                }
 832            }
 833        }
 834
 835        // Set the shear components of the total force.
 836        for (int i=1; i<dim; ++i)
 837            lin_F_.rdof(i) = sforce.dof(i);
 838
 839        // Rolling resistance
 840        DAVect res_M_old = res_M_;
 841        if ((fr_ == 0.0) || (kr_==0.0)) {
 842            res_M_.fill(0.0);
 843        } else {
 844            DAVect angStiff(0.0);
 845            DAVect MomentInc(0.0);
 846#if DIM==3
 847            angStiff.rx() = 0.0;
 848            angStiff.ry() = kr_;
 849#endif
 850            angStiff.rz() = kr_;
 851            MomentInc = ang * angStiff * (-1.0);
 852            res_M_ += MomentInc;
 853            if (state->canFail_) {
 854                // Account for bending strength
 855                double rmax = std::abs(fr_*lin_F_.x());
 856                double rmag = res_M_.mag();
 857                if (rmag >  rmax) {
 858                    double fac = rmax/rmag;
 859                    res_M_ *= fac;
 860                    res_S_ = true;
 861                } else {
 862                    res_S_ = false;
 863                }
 864            }
 865        }
 866
 867        // Account for dashpot forces if the dashpot structure has been defined.
 868        if (dpProps_) {
 869            dpProps_->dp_F_.fill(0.0);
 870            double vcn(0.0), vcs(0.0);
 871            // Calculate the damping coefficients.
 872            setDampCoefficients(state->inertialMass_,&vcn,&vcs);
 873            // First damp the shear components
 874            for (int i=1; i<dim; ++i)
 875                dpProps_->dp_F_.rdof(i) = trans.dof(i) * (-1.0* vcs) / timestep;
 876            // Damp the normal component
 877            dpProps_->dp_F_.rx() -= trans.x() * vcn / timestep;
 878            // Need to change behavior based on the dp_mode.
 879            if ((dpProps_->dp_mode_ == 1 || dpProps_->dp_mode_ == 3))  {
 880                // Limit in tension if not bonded.
 881                if (dpProps_->dp_F_.x() + lin_F_.x() < 0)
 882                    dpProps_->dp_F_.rx() = - lin_F_.rx();
 883            }
 884            if (lin_S_ && dpProps_->dp_mode_ > 1)  {
 885                // Limit in shear if not sliding.
 886                double dfn = dpProps_->dp_F_.rx();
 887                dpProps_->dp_F_.fill(0.0);
 888                dpProps_->dp_F_.rx() = dfn;
 889            }
 890        }
 891
 892        // Adhesive force
 893        double a_F_old = a_F_;
 894        double gs = state->gap_ - rgap_;
 895        a_F_ = 0.0;
 896        if ( gs <= 0.0 )
 897          a_F_ = a_f0_;
 898        else if ( gs <  a_d0_ )  // if a_d0_ == 0.0, will not enter, so next line divide by a_d0_ is ok
 899          a_F_ = a_f0_ * ( 1.0 - (gs/a_d0_) );
 900
 901        //Compute energies if energy tracking has been enabled.
 902        if (state->trackEnergy_) {
 903            assert(energies_);
 904            energies_->estrain_ =  0.0;
 905            if (kn_)
 906                // Calculate the strain energy.
 907                energies_->estrain_ = 0.5*lin_F_.x()*lin_F_.x()/kn_;
 908            if (ks_) {
 909                DVect s = lin_F_;
 910                s.rx() = 0.0;
 911                double smag2 = s.mag2();
 912                // Add the shear component of the strain energy.
 913                energies_->estrain_ += 0.5*smag2 / ks_;
 914
 915                if (lin_S_) {
 916                    // If sliding calculate the slip energy and accumulate it.
 917                    lin_F_old.rx() = 0.0;
 918                    DVect avg_F_s = (s + lin_F_old)*0.5;
 919                    DVect u_s_el =  (s - lin_F_old) / ks_;
 920                    DVect u_s(0.0);
 921                    for (int i=1; i<dim; ++i)
 922                        u_s.rdof(i) = trans.dof(i);
 923                    energies_->eslip_ -= std::min(0.0,(avg_F_s | (u_s + u_s_el)));
 924                }
 925            }
 926            // Add the rolling resistance energy contributions.
 927            energies_->errstrain_ = 0.0;
 928            if (kr_) {
 929                energies_->errstrain_ = 0.5*res_M_.mag2() / kr_;
 930                if (res_S_) {
 931                    // If sliding calculate the slip energy and accumulate it.
 932                    DAVect avg_M = (res_M_ + res_M_old)*0.5;
 933                    DAVect t_s_el =  (res_M_ - res_M_old) / kr_;
 934                    energies_->errslip_ -= std::min(0.0,(avg_M | (ang + t_s_el)));
 935                }
 936            }
 937            // Add the adhesive energy contribution:
 938            energies_->eadhesive_ -= 0.5*(a_F_old + a_F_) * trans.x();
 939
 940            if (dpProps_) {
 941                // Calculate damping energy (accumulated) if the dashpots are active.
 942                energies_->edashpot_ -= dpProps_->dp_F_ | trans;
 943            }
 944        }
 945
 946        // This is just a sanity check to ensure, in debug mode, that the force isn't wonky.
 947        assert(lin_F_ == lin_F_);
 948        return true;
 949    }
 950
 951    bool ContactModelARRLinear::thermalCoupling(ContactModelMechanicalState*, ContactModelThermalState* ts, IContactThermal*, const double&) {
 952        // Account for thermal expansion in incremental mode
 953        if (lin_mode_ == 0 || ts->gapInc_ == 0.0) return false;
 954        DVect finc(0.0);
 955        finc.rx() = kn_ * ts->gapInc_;
 956        lin_F_ -= finc;
 957        return true;
 958    }
 959
 960    void ContactModelARRLinear::setForce(const DVect &v,IContact *c) {
 961        lin_F(v);
 962        if (v.x() > 0)
 963            rgap_ = c->getGap() + v.x() / kn_;
 964    }
 965
 966    void ContactModelARRLinear::propagateStateInformation(IContactModelMechanical* old,const CAxes &oldSystem,const CAxes &newSystem) {
 967        // Only called for contacts with wall facets when the wall resolution scheme
 968        // is set to full!
 969        // Only do something if the contact model is of the same type
 970        if (old->getContactModel()->getName().compare("arrlinear",Qt::CaseInsensitive) == 0 && !isBonded()) {
 971            ContactModelARRLinear *oldCm = (ContactModelARRLinear *)old;
 972#ifdef THREED
 973            // Need to rotate just the shear component from oldSystem to newSystem
 974
 975            // Step 1 - rotate oldSystem so that the normal is the same as the normal of newSystem
 976            DVect axis = oldSystem.e1() & newSystem.e1();
 977            double c, ang, s;
 978            DVect re2;
 979            if (!checktol(axis.abs().maxComp(),0.0,1.0,1000)) {
 980                axis = axis.unit();
 981                c = oldSystem.e1()|newSystem.e1();
 982                if (c > 0)
 983                    c = std::min(c,1.0);
 984                else
 985                    c = std::max(c,-1.0);
 986                ang = acos(c);
 987                s = sin(ang);
 988                double t = 1. - c;
 989                DMatrix<3,3> rm;
 990                rm.get(0,0) = t*axis.x()*axis.x() + c;
 991                rm.get(0,1) = t*axis.x()*axis.y() - axis.z()*s;
 992                rm.get(0,2) = t*axis.x()*axis.z() + axis.y()*s;
 993                rm.get(1,0) = t*axis.x()*axis.y() + axis.z()*s;
 994                rm.get(1,1) = t*axis.y()*axis.y() + c;
 995                rm.get(1,2) = t*axis.y()*axis.z() - axis.x()*s;
 996                rm.get(2,0) = t*axis.x()*axis.z() - axis.y()*s;
 997                rm.get(2,1) = t*axis.y()*axis.z() + axis.x()*s;
 998                rm.get(2,2) = t*axis.z()*axis.z() + c;
 999                re2 = rm*oldSystem.e2();
1000            }
1001            else
1002                re2 = oldSystem.e2();
1003            // Step 2 - get the angle between the oldSystem rotated shear and newSystem shear
1004            axis = re2 & newSystem.e2();
1005            DVect2 tpf;
1006            DVect2 tpm;
1007            DMatrix<2,2> m;
1008            if (!checktol(axis.abs().maxComp(),0.0,1.0,1000)) {
1009                axis = axis.unit();
1010                c = re2|newSystem.e2();
1011                if (c > 0)
1012                    c = std::min(c,1.0);
1013                else
1014                    c = std::max(c,-1.0);
1015                ang = acos(c);
1016                if (!checktol(axis.x(),newSystem.e1().x(),1.0,100))
1017                    ang *= -1;
1018                s = sin(ang);
1019                m.get(0,0) = c;
1020                m.get(1,0) = s;
1021                m.get(0,1) = -m.get(1,0);
1022                m.get(1,1) = m.get(0,0);
1023                tpf = m*DVect2(oldCm->lin_F_.y(),oldCm->lin_F_.z());
1024                tpm = m*DVect2(oldCm->res_M_.y(),oldCm->res_M_.z());
1025            } else {
1026                m.get(0,0) = 1.;
1027                m.get(0,1) = 0.;
1028                m.get(1,0) = 0.;
1029                m.get(1,1) = 1.;
1030                tpf = DVect2(oldCm->lin_F_.y(),oldCm->lin_F_.z());
1031                tpm = DVect2(oldCm->res_M_.y(),oldCm->res_M_.z());
1032            }
1033            DVect pforce = DVect(0,tpf.x(),tpf.y());
1034            //DVect pm     = DVect(0,tpm.x(),tpm.y());
1035#else
1036            oldSystem;
1037            newSystem;
1038            DVect pforce = DVect(0,oldCm->lin_F_.y());
1039            //DVect pm     = DVect(0,oldCm->res_M_.y());
1040#endif
1041            for (int i=1; i<dim; ++i)
1042                lin_F_.rdof(i) += pforce.dof(i);
1043            if (lin_mode_ && oldCm->lin_mode_)
1044                lin_F_.rx() = oldCm->lin_F_.x();
1045            oldCm->lin_F_ = DVect(0.0);
1046            oldCm->res_M_ = DAVect(0.0);
1047            if (dpProps_ && oldCm->dpProps_) {
1048#ifdef THREED
1049                tpf = m*DVect2(oldCm->dpProps_->dp_F_.y(),oldCm->dpProps_->dp_F_.z());
1050                pforce = DVect(oldCm->dpProps_->dp_F_.x(),tpf.x(),tpf.y());
1051#else
1052                pforce = oldCm->dpProps_->dp_F_;
1053#endif
1054                dpProps_->dp_F_ += pforce;
1055                oldCm->dpProps_->dp_F_ = DVect(0.0);
1056            }
1057            if(oldCm->getEnergyActivated()) {
1058                activateEnergy();
1059                energies_->estrain_ = oldCm->energies_->estrain_;
1060                energies_->edashpot_ = oldCm->energies_->edashpot_;
1061                energies_->eslip_ = oldCm->energies_->eslip_;
1062                oldCm->energies_->estrain_ = 0.0;
1063                oldCm->energies_->edashpot_ = 0.0;
1064                oldCm->energies_->eslip_ = 0.0;
1065            }
1066        }
1067        assert(lin_F_ == lin_F_);
1068    }
1069
1070    void ContactModelARRLinear::setNonForcePropsFrom(IContactModel *old) {
1071        // Only called for contacts with wall facets when the wall resolution scheme
1072        // is set to full!
1073        // Only do something if the contact model is of the same type
1074        if (old->getName().compare("arrlinear",Qt::CaseInsensitive) == 0 && !isBonded()) {
1075            ContactModelARRLinear *oldCm = (ContactModelARRLinear *)old;
1076            kn_ = oldCm->kn_;
1077            ks_ = oldCm->ks_;
1078            fric_ = oldCm->fric_;
1079            lin_mode_ = oldCm->lin_mode_;
1080            rgap_ = oldCm->rgap_;
1081            res_fric_ = oldCm->res_fric_;
1082            res_S_ = oldCm->res_S_;
1083            kr_ = oldCm->kr_;
1084            fr_ = oldCm->fr_;
1085            a_f0_ = oldCm->a_f0_;
1086            a_d0_ = oldCm->a_d0_;
1087            userArea_ = oldCm->userArea_;
1088
1089            if (oldCm->dpProps_) {
1090                if (!dpProps_)
1091                    dpProps_ = NEW dpProps();
1092                dpProps_->dp_nratio_ = oldCm->dpProps_->dp_nratio_;
1093                dpProps_->dp_sratio_ = oldCm->dpProps_->dp_sratio_;
1094                dpProps_->dp_mode_ = oldCm->dpProps_->dp_mode_;
1095            }
1096        }
1097    }
1098
1099    DVect ContactModelARRLinear::getForce() const {
1100        DVect ret(lin_F_);
1101        if (dpProps_)
1102            ret += dpProps_->dp_F_;
1103        ret.rdof(0) -= a_F_;
1104        return ret;
1105    }
1106
1107    DAVect ContactModelARRLinear::getMomentOn1(const IContactMechanical *c) const {
1108        DVect force = getForce();
1109        DAVect ret(res_M_);
1110        c->updateResultingTorqueOn1Local(force,&ret);
1111        return ret;
1112    }
1113
1114    DAVect ContactModelARRLinear::getMomentOn2(const IContactMechanical *c) const {
1115        DVect force = getForce();
1116        DAVect ret(res_M_);
1117        c->updateResultingTorqueOn2Local(force,&ret);
1118        return ret;
1119    }
1120    
1121    DAVect ContactModelARRLinear::getModelMomentOn1() const {
1122        DAVect ret(res_M_);
1123        return ret;
1124    }
1125    
1126    DAVect ContactModelARRLinear::getModelMomentOn2() const {
1127        DAVect ret(res_M_);
1128        return ret;
1129    }
1130
1131    void ContactModelARRLinear::objectPropsTypes(std::vector<std::pair<QString,InfoTypes>> *ret) const {
1132        ret->clear();
1133        ret->push_back({"kn",ScalarInfo});
1134        ret->push_back({"ks",ScalarInfo});
1135        ret->push_back({"fric",ScalarInfo});
1136        ret->push_back({"lin_force",VectorInfo});
1137        ret->push_back({"lin_slip",ScalarInfo});
1138        ret->push_back({"lin_mode",ScalarInfo});
1139        ret->push_back({"rgap",ScalarInfo});
1140        ret->push_back({"emod",ScalarInfo});
1141        ret->push_back({"kratio",ScalarInfo});
1142        ret->push_back({"dp_nratio",ScalarInfo});
1143        ret->push_back({"dp_sratio",ScalarInfo});
1144        ret->push_back({"dp_mode",ScalarInfo});
1145        ret->push_back({"dp_force",VectorInfo});
1146        ret->push_back({"rr_fric",ScalarInfo});
1147        ret->push_back({"rr_moment",VectorInfo});
1148        ret->push_back({"rr_slip",ScalarInfo});
1149        ret->push_back({"rr_kr",ScalarInfo});
1150        ret->push_back({"adh_f0",ScalarInfo});
1151        ret->push_back({"adh_d0",ScalarInfo});
1152        ret->push_back({"adh_force",VectorInfo});
1153        ret->push_back({"user_area",ScalarInfo});
1154    }
1155    
1156    void ContactModelARRLinear::objectPropValues(std::vector<double> *ret,const IContact *c) const {
1157        ret->clear();
1158        ret->push_back(kn());
1159        ret->push_back(ks());
1160        ret->push_back(fric());
1161        ret->push_back(lin_F().mag());
1162        ret->push_back(lin_S());
1163        ret->push_back(lin_mode());
1164        ret->push_back(rgap());
1165        ret->push_back(emod(c));
1166        ret->push_back(kratio());
1167        ret->push_back(dp_nratio());
1168        ret->push_back(dp_sratio());
1169        ret->push_back(dp_mode());
1170        ret->push_back(dp_F().mag());
1171        ret->push_back(res_fric());
1172        ret->push_back(res_M().mag());
1173        ret->push_back(res_S());
1174        ret->push_back(kr());
1175        ret->push_back(a_f0());
1176        ret->push_back(a_d0());
1177        ret->push_back(a_F());
1178        ret->push_back(getArea());
1179    }
1180    
1181    double ContactModelARRLinear::emod(const IContact *con) const {
1182        const IContactMechanical *c(convert_getcast<IContactMechanical>(con));
1183        if (c ==nullptr) return 0.0;
1184        double rsq(std::max(c->getEnd1Curvature().y(),c->getEnd2Curvature().y()));
1185        double rsum(0.0);
1186        if (c->getEnd1Curvature().y())
1187            rsum += 1.0/c->getEnd1Curvature().y();
1188        if (c->getEnd2Curvature().y())
1189            rsum += 1.0/c->getEnd2Curvature().y();
1190        if (userArea_) {
1191#ifdef THREED
1192            rsq = std::sqrt(userArea_ / dPi);
1193#else
1194            rsq = userArea_ / 2.0;
1195#endif
1196            rsum = rsq + rsq;
1197            rsq = 1. / rsq;
1198        }
1199#ifdef TWOD
1200        return (kn_ * rsum * rsq / 2.0);
1201#else
1202        return (kn_ * rsum * rsq * rsq) / dPi;
1203#endif
1204    }
1205    
1206    double ContactModelARRLinear::kratio() const {
1207        return (ks_ == 0.0) ? 0.0 : (kn_/ks_);
1208    }
1209
1210    void ContactModelARRLinear::setDampCoefficients(const double &mass,double *vcn,double *vcs) {
1211        *vcn = dpProps_->dp_nratio_ * 2.0 * sqrt(mass*(kn_));
1212        *vcs = dpProps_->dp_sratio_ * 2.0 * sqrt(mass*(ks_));
1213    }
1214
1215} // namespace cmodelsxd
1216// EoF

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