Simbody  3.8
Assembler.h
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1 #ifndef SimTK_SIMBODY_ASSEMBLER_H_
2 #define SimTK_SIMBODY_ASSEMBLER_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) 2010-12 Stanford University and the Authors. *
13  * Authors: Michael Sherman *
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 "SimTKcommon.h"
31 
32 #include <set>
33 #include <map>
34 #include <cassert>
35 #include <cmath>
36 
37 namespace SimTK {
38 
39 SimTK_DEFINE_UNIQUE_INDEX_TYPE(AssemblyConditionIndex);
40 
41 class AssemblyCondition;
42 
149  typedef std::set<MobilizedBodyIndex> LockedMobilizers;
150  typedef std::set<MobilizerQIndex> QSet;
151  typedef std::map<MobilizedBodyIndex, QSet> LockedQs;
152  typedef std::map<MobilizerQIndex, Vec2> QRanges;
153  typedef std::map<MobilizedBodyIndex, QRanges> RestrictedQs;
154 public:
155 
159 
163 class AssembleFailed;
167 class TrackFailed;
168 
186 explicit Assembler(const MultibodySystem& system);
187 
198  SimTK_ERRCHK1_ALWAYS(0 <= tolerance,
199  "Assembler::setTolerance()", "The requested error tolerance %g"
200  " is illegal; we require 0 <= tolerance, with 0 indicating that"
201  " the default tolerance (accuracy/10) is to be used.", tolerance);
202  this->tolerance = tolerance;
203  return *this;
204 }
210  return tolerance > 0 ? tolerance
211  : (accuracy > 0 ? accuracy/10 : Real(0.1)/OODefaultAccuracy);
212 }
213 
223 Assembler& setAccuracy(Real accuracy=0) {
224  SimTK_ERRCHK2_ALWAYS(0 <= accuracy && accuracy < 1,
225  "Assembler::setAccuracy()", "The requested accuracy %g is illegal;"
226  " we require 0 <= accuracy < 1, with 0 indicating that the default"
227  " accuracy (%g) is to be used.", Real(1)/OODefaultAccuracy, accuracy);
228  this->accuracy = accuracy;
229  return *this;
230 }
234 { return accuracy > 0 ? accuracy : Real(1)/OODefaultAccuracy; }
235 
236 
244 { assert(systemConstraints.isValid());
245  setAssemblyConditionWeight(systemConstraints,weight);
246  return *this; }
247 
252 { assert(systemConstraints.isValid());
253  return getAssemblyConditionWeight(systemConstraints); }
254 
261 Assembler& setAssemblyConditionWeight(AssemblyConditionIndex condition,
262  Real weight) {
263  SimTK_INDEXCHECK_ALWAYS(condition, conditions.size(),
264  "Assembler::setAssemblyConditionWeight()");
265  SimTK_ERRCHK1_ALWAYS(weight >= 0, "Assembler::setAssemblyConditionWeight()",
266  "Illegal weight %g; weight must be nonnegative.", weight);
267  uninitialize();
268  weights[condition] = weight;
269  return *this;
270 }
271 
278 Real getAssemblyConditionWeight(AssemblyConditionIndex condition) const {
279  SimTK_INDEXCHECK_ALWAYS(condition, conditions.size(),
280  "Assembler::getAssemblyConditionWeight()");
281  return weights[condition];
282 }
283 
288 AssemblyConditionIndex
298 AssemblyConditionIndex
300 
301 
308  uninitialize();
309  getMatterSubsystem().convertToEulerAngles(state, internalState);
310  system.realizeModel(internalState);
311  return *this;
312 }
319 void initialize() const;
322 void initialize(const State& state)
323 { setInternalState(state); initialize(); }
330 
338 
347 Real track(Real frameTime = -1);
348 
355 Real assemble(State& state) {
356  setInternalState(state);
357  Real achievedCost = assemble(); // throws if it fails
358  updateFromInternalState(state);
359  return achievedCost;
360 }
361 
362 
376 
377 
382 void updateFromInternalState(State& state) const {
383  system.realizeModel(state); // allocates q's if they haven't been yet
384  if (!getMatterSubsystem().getUseEulerAngles(state)) {
385  State tempState;
386  getMatterSubsystem().convertToQuaternions(getInternalState(),
387  tempState);
388  state.updQ() = tempState.getQ();
389  } else
390  state.updQ() = getInternalState().getQ();
391 }
401 
406 { uninitialize(); userLockedMobilizers.insert(mbx); }
413 { uninitialize(); userLockedMobilizers.erase(mbx); }
414 
427 { uninitialize(); userLockedQs[mbx].insert(qx); }
428 
434 { LockedQs::iterator p = userLockedQs.find(mbx);
435  if (p == userLockedQs.end()) return;
436  QSet& qs = p->second;
437  if (qs.erase(qx)) { // returns 0 if nothing erased
438  uninitialize();
439  if (qs.empty())
440  userLockedQs.erase(p); // remove the whole mobilized body
441  }
442 }
443 
450  Real lowerBound, Real upperBound)
451 { SimTK_ERRCHK2_ALWAYS(lowerBound <= upperBound, "Assembler::restrictQ()",
452  "The given range [%g,%g] is illegal because the lower bound is"
453  " greater than the upper bound.", lowerBound, upperBound);
454  if (lowerBound == -Infinity && upperBound == Infinity)
455  { unrestrictQ(mbx,qx); return; }
456  uninitialize();
457  userRestrictedQs[mbx][qx] = Vec2(lowerBound,upperBound);
458 }
459 
460 
466 { RestrictedQs::iterator p = userRestrictedQs.find(mbx);
467  if (p == userRestrictedQs.end()) return;
468  QRanges& qranges = p->second;
469  if (qranges.erase(qx)) { // returns 0 if nothing erased
470  uninitialize();
471  if (qranges.empty())
472  userRestrictedQs.erase(p); // remove the whole mobilized body
473  }
474 }
487 int getNumGoalEvals() const;
489 int getNumErrorEvals() const;
503 void resetStats() const;
511 
515 { forceNumericalGradient = yesno; }
519 { forceNumericalJacobian = yesno; }
520 
526 void setUseRMSErrorNorm(bool yesno)
527 { useRMSErrorNorm = yesno; }
531 bool isUsingRMSErrorNorm() const {return useRMSErrorNorm;}
532 
537 void uninitialize() const;
540 bool isInitialized() const {return alreadyInitialized;}
541 
548 const State& getInternalState() const {return internalState;}
549 
553 void addReporter(const EventReporter& reporter) {
554  reporters.push_back(&reporter);
555 }
556 
560 int getNumFreeQs() const
561 { return freeQ2Q.size(); }
562 
566 QIndex getQIndexOfFreeQ(FreeQIndex freeQIndex) const
567 { return freeQ2Q[freeQIndex]; }
568 
573 FreeQIndex getFreeQIndexOfQ(QIndex qx) const
574 { return q2FreeQ[qx]; }
575 
578 Vec2 getFreeQBounds(FreeQIndex freeQIndex) const {
579  if (!lower.size()) return Vec2(-Infinity, Infinity);
580  else return Vec2(lower[freeQIndex], upper[freeQIndex]);
581 }
582 
587 { return system; }
591 { return system.getMatterSubsystem(); }
597 
598 
599 
600 //------------------------------------------------------------------------------
601  private: // methods
602 //------------------------------------------------------------------------------
603 // Note that the internalState is realized to Stage::Position on return.
604 void setInternalStateFromFreeQs(const Vector& freeQs) {
605  assert(freeQs.size() == getNumFreeQs());
606  Vector& q = internalState.updQ();
607  for (FreeQIndex fx(0); fx < getNumFreeQs(); ++fx)
608  q[getQIndexOfFreeQ(fx)] = freeQs[fx];
609  system.realize(internalState, Stage::Position);
610 }
611 
612 Vector getFreeQsFromInternalState() const {
613  Vector freeQs(getNumFreeQs());
614  const Vector& q = internalState.getQ();
615  for (FreeQIndex fx(0); fx < getNumFreeQs(); ++fx)
616  freeQs[fx] = q[getQIndexOfFreeQ(fx)];
617  return freeQs;
618 }
619 
620 void reinitializeWithExtraQsLocked
621  (const Array_<QIndex>& toBeLocked) const;
622 
623 
624 
625 //------------------------------------------------------------------------------
626  private: // data members
627 //------------------------------------------------------------------------------
628 const MultibodySystem& system;
629 Array_<const EventReporter*> reporters; // just references; don't delete
630 
631 // These members affect the behavior of the assembly algorithm.
632 static const int OODefaultAccuracy = 1000; // 1/accuracy if acc==0
633 Real accuracy; // 0 means use 1/OODefaultAccuracy
634 Real tolerance; // 0 means use accuracy/10
635 bool forceNumericalGradient; // ignore analytic gradient methods
636 bool forceNumericalJacobian; // ignore analytic Jacobian methods
637 bool useRMSErrorNorm; // what norm defines success?
638 
639 // Changes to any of these data members set isInitialized()=false.
640 State internalState;
641 
642 // These are the mobilizers that were set in lockMobilizer(). They are
643 // separate from those involved in individually-locked q's.
644 LockedMobilizers userLockedMobilizers;
645 // These are locks placed on individual q's; they are independent of the
646 // locked mobilizer settings.
647 LockedQs userLockedQs;
648 // These are range restrictions placed on individual q's.
649 RestrictedQs userRestrictedQs;
650 
651 // These are (condition,weight) pairs with weight==Infinity meaning
652 // constraint; weight==0 meaning currently ignored; and any other
653 // positive weight meaning a goal.
654 Array_<AssemblyCondition*,AssemblyConditionIndex>
655  conditions;
656 Array_<Real,AssemblyConditionIndex> weights;
657 
658 // We always have an assembly condition for the Constraints which are
659 // enabled in the System; this is the index which can be used to
660 // retrieve that condition. The default weight is Infinity.
661 AssemblyConditionIndex systemConstraints;
662 
663 
664 // These are filled in when the Assembler is initialized.
665 mutable bool alreadyInitialized;
666 
667 // These are extra q's we removed for numerical reasons.
668 mutable Array_<QIndex> extraQsLocked;
669 
670 // These represent restrictions on the independent variables (q's).
671 mutable std::set<QIndex> lockedQs;
672 mutable Array_<FreeQIndex,QIndex> q2FreeQ; // nq of these
673 mutable Array_<QIndex,FreeQIndex> freeQ2Q; // nfreeQ of these
674 // 0 length if no bounds; otherwise, index by FreeQIndex.
675 mutable Vector lower, upper;
676 
677 // These represent the active assembly conditions.
678 mutable Array_<AssemblyConditionIndex> errors;
679 mutable Array_<int> nTermsPerError;
680 mutable Array_<AssemblyConditionIndex> goals;
681 
682 class AssemblerSystem; // local class
683 mutable AssemblerSystem* asmSys;
684 mutable Optimizer* optimizer;
685 
686 mutable int nAssemblySteps; // count assemble() and track() calls
687 mutable int nInitializations; // # times we had to reinitialize
688 
689 friend class AssemblerSystem;
690 };
691 
692 } // namespace SimTK
693 
694 #endif // SimTK_SIMBODY_ASSEMBLER_H_
#define SimTK_ERRCHK2_ALWAYS(cond, whereChecked, fmt, a1, a2)
Definition: ExceptionMacros.h:289
#define SimTK_INDEXCHECK_ALWAYS(ix, ub, where)
Definition: ExceptionMacros.h:106
#define SimTK_ERRCHK1_ALWAYS(cond, whereChecked, fmt, a1)
Definition: ExceptionMacros.h:285
Includes internal headers providing declarations for the basic SimTK Core classes,...
Every Simbody header and source file should include this header before any other Simbody header.
#define SimTK_SIMBODY_EXPORT
Definition: Simbody/include/simbody/internal/common.h:68
This Study attempts to find a configuration (set of joint coordinates q) of a Simbody MultibodySystem...
Definition: Assembler.h:148
void initialize(const State &state)
Set the internal State and initialize.
Definition: Assembler.h:322
AssemblyConditionIndex adoptAssemblyGoal(AssemblyCondition *p, Real weight=1)
Add an assembly goal to this Assembler study, taking over ownership of the heap-allocated AssemblyCon...
void setForceNumericalJacobian(bool yesno)
This is useful for debugging but should not be used otherwise since the analytic Jacobian is to be pr...
Definition: Assembler.h:518
const MultibodySystem & getMultibodySystem() const
Return a reference to the MultibodySystem associated with this Assembler (that is,...
Definition: Assembler.h:586
bool isUsingRMSErrorNorm() const
Determine whether we are currently using the RMS norm for constraint errors; if not we're using the d...
Definition: Assembler.h:531
int getNumErrorEvals() const
Return the number of assembly error condition evaluations.
Real getAssemblyConditionWeight(AssemblyConditionIndex condition) const
Return the weight currently in use for this AssemblyCondition.
Definition: Assembler.h:278
Assembler(const MultibodySystem &system)
Create an Assembler study for the given MultibodySystem.
void restrictQ(MobilizedBodyIndex mbx, MobilizerQIndex qx, Real lowerBound, Real upperBound)
Restrict a q to remain within a given range.
Definition: Assembler.h:449
~Assembler()
Destruct the Assembler objects and any Assembly Condition objects it contains.
void lockMobilizer(MobilizedBodyIndex mbx)
Lock this mobilizer at its starting position.
Definition: Assembler.h:405
Real calcCurrentErrorNorm() const
This is the weighted norm of the assembly constraint errors directly comparable with the assembly err...
Real getAccuracyInUse() const
Obtain the accuracy setting that will be used during the next assemble() or track() call.
Definition: Assembler.h:233
void setForceNumericalGradient(bool yesno)
This is useful for debugging but should not be used otherwise since the analytic gradient is to be pr...
Definition: Assembler.h:514
Assembler & setAssemblyConditionWeight(AssemblyConditionIndex condition, Real weight)
Set the weight to be used for this AssemblyCondition.
Definition: Assembler.h:261
void resetStats() const
Reset all counters to zero; except for the number of initializations counter this also happens whenev...
Real calcCurrentGoal() const
Return the goal value attained by the internal State's current settings for the free q's; this is a w...
Real assemble(State &state)
Given an initial value for the State, modify the q's in it to satisfy all the assembly conditions to ...
Definition: Assembler.h:355
int getNumAssemblySteps() const
Return the number of assembly steps; that is, the number of calls to assemble() or track() since last...
AssemblyConditionIndex adoptAssemblyError(AssemblyCondition *p)
Add an assembly error condition to this Assembler study, taking over ownership of the heap-allocated ...
Vec2 getFreeQBounds(FreeQIndex freeQIndex) const
Return the allowable range for a particular free q.
Definition: Assembler.h:578
int getNumErrorJacobianEvals() const
Return the number of assembly error condition Jacobian evaluations.
QIndex getQIndexOfFreeQ(FreeQIndex freeQIndex) const
Return the absolute q index associated with a free q.
Definition: Assembler.h:566
int getNumFreeQs() const
Return the number of q's which are free to be changed by this already-initialized assembly analysis.
Definition: Assembler.h:560
Assembler & setSystemConstraintsWeight(Real weight)
Change how the System's enabled built-in Constraints are weighted as compared to other assembly condi...
Definition: Assembler.h:243
int getNumGoalEvals() const
Return the number of goal evaluations.
void unlockMobilizer(MobilizedBodyIndex mbx)
Unlock this mobilizer as a whole; some of its q's may remain locked if they were locked individually.
Definition: Assembler.h:412
void lockQ(MobilizedBodyIndex mbx, MobilizerQIndex qx)
Lock one of this mobilizer's q's at its initial value.
Definition: Assembler.h:426
FreeQIndex getFreeQIndexOfQ(QIndex qx) const
A subset of the q's will be used as free q's for solving the assembly problem.
Definition: Assembler.h:573
void addReporter(const EventReporter &reporter)
Given a reference to an EventReporter, use this Reporter to provide progress reporting.
Definition: Assembler.h:553
int getNumInitializations() const
Return the number of system initializations performed since this Assembler was created or the most re...
bool isInitialized() const
Check whether the Assembler has been initialized since the last change was made to its contents.
Definition: Assembler.h:540
Assembler & setAccuracy(Real accuracy=0)
Set the accuracy to which a solution should be pursued.
Definition: Assembler.h:223
void unlockQ(MobilizedBodyIndex mbx, MobilizerQIndex qx)
Unlock one of this mobilizer's q's if it was locked.
Definition: Assembler.h:433
Assembler & setInternalState(const State &state)
Set the Assembler's internal state from an existing state which must be suitable for use with the Ass...
Definition: Assembler.h:307
void setUseRMSErrorNorm(bool yesno)
Use an RMS norm for the assembly errors rather than the default infinity norm (max absolute value).
Definition: Assembler.h:526
Real assemble()
Starting with the current value of the internally-maintained State, modify the q's in it to satisfy a...
const SimbodyMatterSubsystem & getMatterSubsystem() const
Return a reference to the SimbodyMatterSubsystem that is contained in the MultibodySystem that is ass...
Definition: Assembler.h:590
Real getErrorToleranceInUse() const
Obtain the tolerance setting that will be used during the next assemble() or track() call.
Definition: Assembler.h:209
void uninitialize() const
Uninitialize the Assembler.
void updateFromInternalState(State &state) const
Given an existing State that is suitable for the Assembler's System, update its q's from those found ...
Definition: Assembler.h:382
void initialize() const
Initialize the Assembler to prepare for performing assembly analysis.
int getNumGoalGradientEvals() const
Return the number of goal gradient evaluations.
Assembler & setErrorTolerance(Real tolerance=0)
Set the assembly error tolerance.
Definition: Assembler.h:197
SimTK_DEFINE_UNIQUE_LOCAL_INDEX_TYPE(Assembler, FreeQIndex)
Assembler::FreeQIndex is a unique integer type used for accessing the subset of q's that the Assemble...
const State & getInternalState() const
This provides read-only access to the Assembler's internal State; you probably should use updateFromI...
Definition: Assembler.h:548
Real getSystemConstraintsWeight() const
Return the current weight being given to the System's built-in Constraints; the default is Infinity.
Definition: Assembler.h:251
Real track(Real frameTime=-1)
Continue a series of assembly steps that is already in progress, without restarting or reanalyzing th...
void unrestrictQ(MobilizedBodyIndex mbx, MobilizerQIndex qx)
Unrestrict a particular generalized coordinate q if it was previously restricted.
Definition: Assembler.h:465
Define an assembly condition consisting of a scalar goal and/or a related set of assembly error equat...
Definition: AssemblyCondition.h:44
An EventReporter is an object that defines an event that can occur within a system.
Definition: EventReporter.h:53
This is for arrays indexed by mobilized body number within a subsystem (typically the SimbodyMatterSu...
The Mobilizer associated with each MobilizedBody, once modeled, has a specific number of generalized ...
The job of the MultibodySystem class is to coordinate the activities of various subsystems which can ...
Definition: MultibodySystem.h:48
Unique integer type for Subsystem-local q indexing.
This subsystem contains the bodies ("matter") in the multibody system, the mobilizers (joints) that d...
Definition: SimbodyMatterSubsystem.h:133
@ Position
Spatial configuration available.
Definition: Stage.h:74
This object is intended to contain all state information for a SimTK::System, except topological info...
Definition: State.h:280
Vector & updQ(SubsystemIndex)
const Vector & getQ(SubsystemIndex) const
Per-subsystem access to the global shared variables.
Definition: Study.h:56
int size() const
Definition: VectorBase.h:396
Vec< 2 > Vec2
This is the most common 2D vector type: a column of 2 Real values stored consecutively in memory (pac...
Definition: SmallMatrix.h:126
Vector_< Real > Vector
Variable-size column vector of Real elements; abbreviation for Vector_<Real>.
Definition: BigMatrix.h:1477
const Real Infinity
This is the IEEE positive infinity constant for this implementation of the default-precision Real typ...
This is the top-level SimTK namespace into which all SimTK names are placed to avoid collision with o...
Definition: Assembler.h:37
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:607
SimTK_DEFINE_UNIQUE_INDEX_TYPE(AssemblyConditionIndex)