Simbody  3.5
SemiExplicitEulerTimeStepper.h
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1 #ifndef SimTK_SIMBODY_SEMI_EXPLICIT_EULER_TIME_STEPPER_H_
2 #define SimTK_SIMBODY_SEMI_EXPLICIT_EULER_TIME_STEPPER_H_
3 
4 /* -------------------------------------------------------------------------- *
5  * Simbody(tm) *
6  * -------------------------------------------------------------------------- *
7  * This is part of the SimTK biosimulation toolkit originating from *
8  * Simbios, the NIH National Center for Physics-Based Simulation of *
9  * Biological Structures at Stanford, funded under the NIH Roadmap for *
10  * Medical Research, grant U54 GM072970. See https://simtk.org/home/simbody. *
11  * *
12  * Portions copyright (c) 2014 Stanford University and the Authors. *
13  * Authors: Michael Sherman, Thomas Uchida *
14  * Contributors: *
15  * *
16  * Licensed under the Apache License, Version 2.0 (the "License"); you may *
17  * not use this file except in compliance with the License. You may obtain a *
18  * copy of the License at http://www.apache.org/licenses/LICENSE-2.0. *
19  * *
20  * Unless required by applicable law or agreed to in writing, software *
21  * distributed under the License is distributed on an "AS IS" BASIS, *
22  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
23  * See the License for the specific language governing permissions and *
24  * limitations under the License. *
25  * -------------------------------------------------------------------------- */
26 
27 #include "SimTKmath.h"
33 
34 namespace SimTK {
35 
53 public:
66  enum RestitutionModel {Poisson=0, Newton=1, NoRestitution=2};
67  enum InducedImpactModel {Simultaneous=0, Sequential=1, Mixed=2};
68  enum PositionProjectionMethod {Bilateral=0,Unilateral=1,
69  NoPositionProjection=2};
70  enum ImpulseSolverType {PLUS=0, PGS=1};
71 
72 
73  explicit SemiExplicitEulerTimeStepper(const MultibodySystem& mbs);
74 
78  clearImpulseSolver();
79  }
80 
84  void initialize(const State& initState);
86  const State& getState() const {return m_state;}
89  State& updState() {return m_state;}
92  Real getTime() const {return m_state.getTime();}
93 
95  const State& getAdvancedState() const {return m_state;}
96 
98  State& updAdvancedState() {return m_state;}
99 
101  Real getAdvancedTime() const {return m_state.getTime();}
102 
106 
108  void setAccuracy(Real accuracy) {m_accuracy=accuracy;}
110  void setConstraintTolerance(Real consTol) {m_consTol=consTol;}
111 
113  { m_restitutionModel = restModel; }
115  { return m_restitutionModel; }
116 
118  { m_inducedImpactModel = indModel; }
120  { return m_inducedImpactModel; }
121 
131  void setMaxInducedImpactsPerStep(int maxInduced) {
132  SimTK_APIARGCHECK1_ALWAYS(maxInduced>=0, "SemiExplicitEulerTimeStepper",
133  "setMaxInducedImpactsPerStep", "Illegal argument %d", maxInduced);
134  m_maxInducedImpactsPerStep = maxInduced;
135  }
137  { return m_maxInducedImpactsPerStep; }
138 
140  { m_projectionMethod = projMethod; }
142  { return m_projectionMethod; }
143 
145  if (m_solverType != solverType) {
146  // The new solver will get allocated in initialize().
147  clearImpulseSolver();
148  m_solverType = solverType;
149  }
150  }
152  { return m_solverType; }
153 
163  SimTK_ERRCHK1_ALWAYS(vCapture>=0,
164  "SemiExplicitEulerTimeStepper::setDefaultImpactCaptureVelocity()",
165  "The impact capture velocity must be nonnegative but was %g.",
166  vCapture);
167  m_defaultCaptureVelocity = vCapture;
168  }
169 
178  SimTK_ERRCHK1_ALWAYS(vMinCOR>=0,
179  "SemiExplicitEulerTimeStepper::setDefaultImpactMinCORVelocity()",
180  "The velocity at which the minimum coefficient of restitution "
181  " is reached must be nonnegative but was %g.", vMinCOR);
182  m_defaultMinCORVelocity = vMinCOR;
183  }
184 
194  SimTK_ERRCHK1_ALWAYS(vTransition>=0,
195  "SemiExplicitEulerTimeStepper::setDefaultFrictionTransitionVelocity()",
196  "The friction transition velocity must be nonnegative but was %g.",
197  vTransition);
198  m_defaultTransitionVelocity = vTransition;
199  }
200 
205  void setMinSignificantForce(Real minSignificantForce) {
206  SimTK_ERRCHK1_ALWAYS(minSignificantForce>0,
207  "SemiExplicitEulerTimeStepper::setMinSignificantForce()",
208  "The minimum significant force magnitude must be greater than zero "
209  "but was %g.", minSignificantForce);
210  m_minSignificantForce = minSignificantForce;
211  }
213  { return m_minSignificantForce; }
214 
217  Real getAccuracyInUse() const {return m_accuracy;}
218 
223  Real getConstraintToleranceInUse() const {return m_consTol;}
224 
229  { return m_defaultCaptureVelocity; }
234  { return m_defaultMinCORVelocity; }
239  { return m_defaultTransitionVelocity; }
240 
244  { return std::max(m_defaultCaptureVelocity, 2*m_consTol); }
248  { return std::max(m_defaultMinCORVelocity,
249  getDefaultImpactCaptureVelocityInUse()); }
253  { return std::max(m_defaultTransitionVelocity, 2*m_consTol); }
254 
257  const MultibodySystem& getMultibodySystem() const {return m_mbs;}
258 
259 
262  SimTK_ERRCHK_ALWAYS(m_solver!=0,
263  "SemiExplicitEulerTimeStepper::getImpulseSolver()",
264  "No solver is currently allocated.");
265  return *m_solver;
266  }
269  void setImpulseSolver(ImpulseSolver* impulseSolver) {
270  clearImpulseSolver();
271  m_solver = impulseSolver;
272  }
275  delete m_solver; m_solver=0;
276  }
277 
279  static const char* getRestitutionModelName(RestitutionModel rm);
281  static const char* getInducedImpactModelName(InducedImpactModel iim);
283  static const char* getPositionProjectionMethodName
286  static const char* getImpulseSolverTypeName(ImpulseSolverType ist);
287 
288 private:
289  // Determine which constraints will be involved for this step.
290  void findProximalConstraints(const State&);
291  // Enable all proximal constraints, disable all distal constraints,
292  // reassigning multipliers if needed. Returns true if anything changed.
293  bool enableProximalConstraints(State&);
294  // After constraints are enabled, gather up useful info about them.
295  void collectConstraintInfo(const State& s);
296  // Calculate velocity-dependent coefficients of restitution and friction
297  // and apply combining rules for dissimilar materials.
298  void calcCoefficientsOfFriction(const State&, const Vector& verr);
299  void calcCoefficientsOfRestitution(const State&, const Vector& verr,
300  bool disableRestitution);
301 
302  // Easy if there are no constraints active.
303  void takeUnconstrainedStep(State& s, Real h);
304 
305  // If we're in Newton restitution mode, calculating the verr change
306  // that is needed to represent restitution. Output must already be
307  // the same size as verr on entry if we're in Newton mode.
308  bool calcNewtonRestitutionIfAny(const State&, const Vector& verr,
309  Vector& newtonVerr) const;
310 
311  // Adjust given compression impulse to include Poisson restitution impulse.
312  // Note which contacts are expanding.
313  bool applyPoissonRestitutionIfAny(const State&, Vector& impulse,
314  Array_<int>& expanders) const;
315 
316  bool calcExpansionImpulseIfAny(const State& s, const Array_<int>& impacters,
317  const Vector& compressionImpulse,
318  Vector& expansionImpulse,
319  Array_<int>& expanders) const;
320 
321  // Perform a simultaneous impact if needed. All proximal constraints are
322  // dealt with so after this call there will be no more impacters, and no
323  // unapplied expansion impulses. For Poisson restitution this may be a
324  // compression/expansion impulse pair (and rarely a final compression
325  // round to correct expanders that were forced back into impacting).
326  // For Newton restitution only a single impulse round is calculated.
327  // Returns the number of impulse rounds actually taken, usually zero.
328  int performSimultaneousImpact(const State& state,
329  Vector& verr, // in/out
330  Vector& totalImpulse);
331 
332  // We identify impacters, observers, and expanders then perform a single
333  // impulse calculation that ignores the observers. On return there may
334  // be former observers and expanders that now have impacting approach
335  // velocities so will be impacters on the next round. For Poisson
336  // restitution, there may be expansion impulses that have not yet been
337  // applied; those contacts will be expanders on the next round.
338  bool performInducedImpactRound(const Vector& verr,
339  const Vector& expansionImpulse);
340 
341  void classifyUnilateralContactsForSequentialImpact
342  (const Vector& verr,
343  const Vector& expansionImpulse,
344  bool includeAllProximals,
345  bool expansionOnly,
347  Array_<int>& impacters,
348  Array_<int>& expanders,
349  Array_<int>& observers,
350  Array_<MultiplierIndex>& participaters,
351  Array_<MultiplierIndex>& expanding) const;
352 
353 
354  void classifyUnilateralContactsForSimultaneousImpact
355  (const Vector& verr,
356  const Vector& expansionImpulse,
358  Array_<int>& impacters,
359  Array_<int>& expanders,
360  Array_<int>& observers,
361  Array_<MultiplierIndex>& participaters,
362  Array_<MultiplierIndex>& expanding) const;
363 
364  // This phase uses all the proximal constraints and should use a starting
365  // guess for impulse saved from the last step if possible.
366  bool doCompressionPhase(const State& state,
367  Vector& verrStart, // in/out
368  Vector& verrApplied, // in/out
369  Vector& compressionImpulse);
370  // This phase uses all the proximal constraints, but we expect the result
371  // to be zero unless expansion causes new violations.
372  bool doExpansionPhase(const State& state,
373  const Array_<MultiplierIndex>& expanding,
374  Vector& expansionImpulse,
375  Vector& verrStart, // in/out
376  Vector& reactionImpulse);
377  bool doInducedImpactRound(const State& state,
378  const Array_<MultiplierIndex>& expanding,
379  Vector& expansionImpulse,
380  Vector& verrStart, // in/out
381  Vector& impulse);
382  bool anyPositionErrorsViolated(const State&, const Vector& perr) const;
383 
384  // This phase uses only holonomic constraints, and zero is a good initial
385  // guess for the (hopefully small) position correction.
386  bool doPositionCorrectionPhase(const State& state,
387  Vector& pverr, // in/out
388  Vector& positionImpulse);
389 
390 
391 private:
392  const MultibodySystem& m_mbs;
393  Real m_accuracy;
394  Real m_consTol;
395  RestitutionModel m_restitutionModel;
396  InducedImpactModel m_inducedImpactModel;
397  int m_maxInducedImpactsPerStep;
398  PositionProjectionMethod m_projectionMethod;
399  ImpulseSolverType m_solverType;
400 
401 
402  Real m_defaultCaptureVelocity;
403  Real m_defaultMinCORVelocity;
404  Real m_defaultTransitionVelocity;
405  Real m_minSignificantForce;
406 
407  ImpulseSolver* m_solver;
408 
409  // Persistent runtime data.
410  State m_state;
411  Vector m_emptyVector; // don't change this!
412 
413  // Step temporaries.
414  Matrix m_GMInvGt; // G M\ ~G
415  Vector m_D; // soft diagonal
416  Vector m_deltaU;
417  Vector m_verr;
418  Vector m_totalImpulse;
419  Vector m_impulse;
420  Vector m_genImpulse; // ~G*impulse
421 
422  Array_<UnilateralContactIndex> m_proximalUniContacts,
423  m_distalUniContacts;
424  Array_<StateLimitedFrictionIndex> m_proximalStateLtdFriction,
425  m_distalStateLtdFriction;
426 
427  // This is for use in the no-impact phase where all proximals participate.
428  Array_<MultiplierIndex> m_allParticipating;
429 
430  // These are for use in impact phases.
431  Array_<MultiplierIndex> m_participating;
432  Array_<MultiplierIndex> m_expanding;
433  Vector m_expansionImpulse;
434  Vector m_newtonRestitutionVerr;
435  Array_<int> m_impacters;
436  Array_<int> m_expanders;
437  Array_<int> m_observers;
438 
439  Array_<ImpulseSolver::UncondRT> m_unconditional;
440  Array_<ImpulseSolver::UniContactRT> m_uniContact; // with fric
445 
446  // These lists are for use in position projection and include only
447  // holonomic constraints (the unilateral contacts have friction off).
448  Array_<MultiplierIndex> m_posParticipating;
449  Array_<ImpulseSolver::UncondRT> m_posUnconditional;
450  Array_<ImpulseSolver::UniContactRT> m_posUniContact; // no fric
451  Array_<ImpulseSolver::UniSpeedRT> m_posNoUniSpeed;
452  Array_<ImpulseSolver::BoundedRT> m_posNoBounded;
453  Array_<ImpulseSolver::ConstraintLtdFrictionRT> m_posNoConsLtdFriction;
454  Array_<ImpulseSolver::StateLtdFrictionRT> m_posNoStateLtdFriction;
455 };
456 
457 } // namespace SimTK
458 
459 #endif // SimTK_SIMBODY_SEMI_EXPLICIT_EULER_TIME_STEPPER_H_
460 
Real getDefaultImpactCaptureVelocityInUse() const
Return the value actually being used as the default impact capture velocity.
Definition: SemiExplicitEulerTimeStepper.h:243
void setConstraintTolerance(Real consTol)
Set the tolerance to which constraints must be satisfied.
Definition: SemiExplicitEulerTimeStepper.h:110
const ImpulseSolver & getImpulseSolver() const
(Advanced) Get direct access to the ImpulseSolver.
Definition: SemiExplicitEulerTimeStepper.h:261
#define SimTK_APIARGCHECK1_ALWAYS(cond, className, methodName, fmt, a1)
Definition: ExceptionMacros.h:228
void setDefaultImpactCaptureVelocity(Real vCapture)
Set the impact capture velocity to be used by default when a contact does not provide its own...
Definition: SemiExplicitEulerTimeStepper.h:162
Real getConstraintToleranceInUse() const
Return the tolerance to which we require constraints to be satisfied.
Definition: SemiExplicitEulerTimeStepper.h:223
Real getAccuracyInUse() const
Return the integration accuracy setting.
Definition: SemiExplicitEulerTimeStepper.h:217
Real getDefaultFrictionTransitionVelocityInUse() const
Return the value actually being used as the default sliding-to-rolling friction transition velocity...
Definition: SemiExplicitEulerTimeStepper.h:252
#define SimTK_ERRCHK1_ALWAYS(cond, whereChecked, fmt, a1)
Definition: ExceptionMacros.h:285
This is the top-level SimTK namespace into which all SimTK names are placed to avoid collision with o...
Definition: Assembler.h:37
Real getMinSignificantForce() const
Definition: SemiExplicitEulerTimeStepper.h:212
A low-accuracy, high performance, velocity-level time stepper for models containing unilateral rigid ...
Definition: SemiExplicitEulerTimeStepper.h:52
void setPositionProjectionMethod(PositionProjectionMethod projMethod)
Definition: SemiExplicitEulerTimeStepper.h:139
This is the abstract base class for impulse solvers, which solve an important subproblem of the conta...
Definition: ImpulseSolver.h:109
void setAccuracy(Real accuracy)
Set integration accuracy; requires variable length steps.
Definition: SemiExplicitEulerTimeStepper.h:108
Every Simbody header and source file should include this header before any other Simbody header...
void setImpulseSolver(ImpulseSolver *impulseSolver)
(Advanced) Set your own ImpulseSolver; the TimeStepper takes over ownership so don&#39;t delete afterward...
Definition: SemiExplicitEulerTimeStepper.h:269
void setImpulseSolverType(ImpulseSolverType solverType)
Definition: SemiExplicitEulerTimeStepper.h:144
Real getDefaultImpactMinCORVelocity() const
Return the value set for this parameter, but the actual value used during execution will be no smalle...
Definition: SemiExplicitEulerTimeStepper.h:233
SimTK_Real Real
This is the default compiled-in floating point type for SimTK, either float or double.
Definition: SimTKcommon/include/SimTKcommon/internal/common.h:593
Real getAdvancedTime() const
synonym for getTime.
Definition: SemiExplicitEulerTimeStepper.h:101
void clearImpulseSolver()
(Advanced) Delete the existing ImpulseSolver if any.
Definition: SemiExplicitEulerTimeStepper.h:274
F Ю IС A7 Ю Ю Ж Е e2 Ь Н6 УJ џџџџ Алў ПЪ …8 q2 L F є F И Н6 F Н6 p IС IС Ю IС IС IС IС IС C7 C7 Ю IС IС IС IС IС IС IС џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ џџџџ F IС IС IС IС IС IС IС IС IС т Michael Peter Eastman Permission is hereby free of to any person obtaining a copy of this to deal in the Document without including without limitation the rights to and or sell copies of the and to permit persons to whom the Document is furnished to do subject to the following WITHOUT WARRANTY OF ANY EXPRESS OR INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT IN NO EVENT SHALL THE CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY DAMAGES OR OTHER WHETHER IN AN ACTION OF TORT OR ARISING OUT OF OR IN CONNECTION WITH THE DOCUMENT OR THE USE OR OTHER DEALINGS IN THE DOCUMENT Acknowledgment SimTK software and all related activities are funded by the HYPERLINK vectors and matrices PAGEREF _Toc251069768 h HYPERLINK l _Toc251069769 Linear algebra PAGEREF _Toc251069769 h HYPERLINK l _Toc251069770 Solving Linear Systems(SimTK::FactorLU)PAGEREF _Toc251069770\h5HYPERLINK\l"_Toc251069771"3.2 Linear Least Squares(SimTK otherwise the best guess is that tevent is in the middle of the window Finite width localization windows create a likelihood that multiple events will occur within the same window We cannot say with certainty in what order these events so for precise treatment they must be considered simultaneous If an approximate ordering is acceptable then the integrator’s tevent guesses can be used to order the events within the but even those may be identical for some and in any case the integrator cannot guarantee that the events actually occurred in the order they appear when sorted by estimated time of occurrence If more precise information is then the localization window must be made at the cost of increased computation time Once an event has been localized to an acceptable the integrator’s stepTo() method will return control to the time stepper at time tlow
This object is intended to contain all state information for a SimTK::System, except topological info...
Definition: State.h:276
void setMinSignificantForce(Real minSignificantForce)
Set the threshold below which we can ignore forces.
Definition: SemiExplicitEulerTimeStepper.h:205
void setRestitutionModel(RestitutionModel restModel)
Definition: SemiExplicitEulerTimeStepper.h:112
~SemiExplicitEulerTimeStepper()
The contained ImpulseSolver will be destructed here; don&#39;t reference it afterwards! ...
Definition: SemiExplicitEulerTimeStepper.h:77
that it contains events that have triggered but have not been processed Thus it is not a legitimate point along the system’s trajectory and should never be returned to the caller For discussion we label this “improper” state EMBED Equation DSMT4 The event handler will correct the state creating a modified state with time still at thigh but not triggering any events We label the modified state EMBED Equation DSMT4 Once the system’s handler the state EMBED Equation DSMT4 can be output as part of the trajectory and used as the initial condition for the next continuous interval Thus the time stepper generates the sequence of legitimate trajectory points just prior to event immediately followed by EMBED Equation DSMT4 which is the time at which the but after the event handler has modified the state to deal with those events Consecutive intervals I and I will consist of trajectory points EMBED Equation DSMT4 with round brackets indicating that EMBED Equation DSMT4 is not part of the trajectory Event handlers Event handlers are solvers which are able to take a state in an resolve the set up appropriate event triggers for the next and report back to the time stepper the degree to which the system continuity has been so that the integrator can be reinitialized appropriately An event handler can also indicate that the simulation should be in which case the time stepper will return the final state to its caller and disallow further time stepping Other event types Not all events have to be localized There are several special case clock time
Definition: SimmathUserGuide.doc:219
RestitutionModel
If an impact occurs at a contact where the coefficient of restitution (COR) is non zero...
Definition: SemiExplicitEulerTimeStepper.h:66
void setInducedImpactModel(InducedImpactModel indModel)
Definition: SemiExplicitEulerTimeStepper.h:117
#define SimTK_ERRCHK_ALWAYS(cond, whereChecked, msg)
Definition: ExceptionMacros.h:281
ImpulseSolverType getImpulseSolverType() const
Definition: SemiExplicitEulerTimeStepper.h:151
InducedImpactModel getInducedImpactModel() const
Definition: SemiExplicitEulerTimeStepper.h:119
ELEM max(const VectorBase< ELEM > &v)
Definition: VectorMath.h:251
The job of the MultibodySystem class is to coordinate the activities of various subsystems which can ...
Definition: MultibodySystem.h:48
Real getDefaultImpactMinCORVelocityInUse() const
Return the value actually being used as the default impact minimum coefficient of restitution velocit...
Definition: SemiExplicitEulerTimeStepper.h:247
аЯ рЁБ с ўџ З Й ўџџџ Г Д Е Ж џџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџџьЅС € ј П ч bjbjcTcT кй Г У Л t џџ џџ џџ З Ÿ С K K K D џџџџ    € ‹2 ”  ZЦ j J a n u a r A b s t r a c t W e d e s c r i b e t h e g o a l s a n d d e s i g n d e c i s i o n b e h i n d S i m m a t r i t h e S i m T K m a t r i x a n d l i n e a r a l g e b r a l i b r a r a n d p r o v i d e r e f e r e n c e i n f o r m a t i o n f o r u s i n g i t T h e i d e a i s t o p r o v i d e t h e p o w e n a t u r a l n e s s
Definition: Simmatrix.doc:7
const State & getAdvancedState() const
synonym for getState.
Definition: SemiExplicitEulerTimeStepper.h:95
void setMaxInducedImpactsPerStep(int maxInduced)
Limit the number of induced impact rounds per time step.
Definition: SemiExplicitEulerTimeStepper.h:131
void setDefaultFrictionTransitionVelocity(Real vTransition)
Set the friction sliding-to-rolling transition velocity to be used by default when a frictional conta...
Definition: SemiExplicitEulerTimeStepper.h:193
State & updState()
Get writable access to the TimeStepper&#39;s internally maintained State.
Definition: SemiExplicitEulerTimeStepper.h:89
InducedImpactModel
Definition: SemiExplicitEulerTimeStepper.h:67
SuccessfulStepStatus
When a step is successful, it will return an indication of what caused it to stop where it did...
Definition: Integrator.h:202
PositionProjectionMethod
Definition: SemiExplicitEulerTimeStepper.h:68
#define SimTK_SIMBODY_EXPORT
Definition: Simbody/include/simbody/internal/common.h:72
Real getTime() const
Shortcut to getting the current time from the TimeStepper&#39;s internally maintained State...
Definition: SemiExplicitEulerTimeStepper.h:92
ImpulseSolverType
Definition: SemiExplicitEulerTimeStepper.h:70
Real getDefaultImpactCaptureVelocity() const
Return the value set for this parameter, but the actual value used during execution will be no smalle...
Definition: SemiExplicitEulerTimeStepper.h:228
PositionProjectionMethod getPositionProjectionMethod() const
Definition: SemiExplicitEulerTimeStepper.h:141
void setDefaultImpactMinCORVelocity(Real vMinCOR)
Set the minimum coefficient of restitution (COR) velocity to be used by default when a unilateral con...
Definition: SemiExplicitEulerTimeStepper.h:177
const MultibodySystem & getMultibodySystem() const
Get access to the MultibodySystem for which this TimeStepper was constructed.
Definition: SemiExplicitEulerTimeStepper.h:257
const State & getState() const
Get access to the TimeStepper&#39;s internally maintained State.
Definition: SemiExplicitEulerTimeStepper.h:86
RestitutionModel getRestitutionModel() const
Definition: SemiExplicitEulerTimeStepper.h:114
int getMaxInducedImpactsPerStep() const
Definition: SemiExplicitEulerTimeStepper.h:136
State & updAdvancedState()
synonym for updState.
Definition: SemiExplicitEulerTimeStepper.h:98
Real getDefaultFrictionTransitionVelocity() const
Return the value set for this parameter, but the actual value used during execution will be no smalle...
Definition: SemiExplicitEulerTimeStepper.h:238