chrono::ChPhysicsItem Class Reference

Description

Base class for physics items that are part of a simulation.

Such items (e.g., rigid bodies, joints, FEM meshes, etc.) can contain ChVariables or ChConstraints objects.

#include <ChPhysicsItem.h>

Inheritance diagram for chrono::ChPhysicsItem:
Collaboration diagram for chrono::ChPhysicsItem:

Public Member Functions

 ChPhysicsItem (const ChPhysicsItem &other)
 
virtual ChPhysicsItemClone () const override
 "Virtual" copy constructor (covariant return type).
 
ChSystemGetSystem () const
 Get the pointer to the parent ChSystem().
 
virtual void SetSystem (ChSystem *m_system)
 Set the pointer to the parent ChSystem(). More...
 
void AddVisualModel (std::shared_ptr< ChVisualModel > model)
 Add an (optional) visualization model. More...
 
std::shared_ptr< ChVisualModelGetVisualModel () const
 Access the visualization model (if any). More...
 
void AddVisualShape (std::shared_ptr< ChVisualShape > shape, const ChFrame<> &frame=ChFrame<>())
 Add the specified visual shape to the visualization model. More...
 
std::shared_ptr< ChVisualShapeGetVisualShape (unsigned int i) const
 Access the specified visualization shape in the visualization model (if any). More...
 
void AddVisualShapeFEA (std::shared_ptr< ChVisualShapeFEA > shapeFEA)
 Add the specified FEA visualization object to the visualization model. More...
 
std::shared_ptr< ChVisualShapeFEAGetVisualShapeFEA (unsigned int i) const
 Access the specified FEA visualization object in the visualization model (if any). More...
 
virtual ChFrame GetVisualModelFrame (unsigned int nclone=0) const
 Get the reference frame (expressed in and relative to the absolute frame) of the visual model. More...
 
virtual unsigned int GetNumVisualModelClones () const
 Return the number of clones of the visual model associated with this physics item. More...
 
void AddCamera (std::shared_ptr< ChCamera > camera)
 Attach a ChCamera to this physical item. More...
 
std::vector< std::shared_ptr< ChCamera > > GetCameras () const
 Get the set of cameras attached to this physics item.
 
virtual bool IsActive () const
 Return true if the object is active and included in dynamics.
 
virtual bool IsCollisionEnabled () const
 Tell if the object is subject to collision. More...
 
virtual void AddCollisionModelsToSystem (ChCollisionSystem *coll_sys) const
 Add to the provided collision system any collision models managed by this physics item. More...
 
virtual void RemoveCollisionModelsFromSystem (ChCollisionSystem *coll_sys) const
 Remove from the provided collision system any collision models managed by this physics item. More...
 
virtual void SyncCollisionModels ()
 Synchronize the position and bounding box of any collsion models managed by this physics item.
 
virtual ChAABB GetTotalAABB ()
 Get the entire AABB axis-aligned bounding box of the object. More...
 
virtual void GetCenter (ChVector3d &mcenter)
 Get a symbolic 'center' of the object. More...
 
virtual void Setup ()
 This might recompute the number of coordinates, DOFs, constraints, in case this might change (ex in ChAssembly), as well as state offsets of contained items (ex in ChMesh)
 
virtual void Update (double mytime, bool update_assets=true)
 This is an important function, which is called by the owner ChSystem at least once per integration step. More...
 
virtual void Update (bool update_assets=true)
 As above, but does not require updating of time-dependent data. More...
 
virtual void ForceToRest ()
 Set zero speed (and zero accelerations) in state, without changing the position. More...
 
virtual unsigned int GetNumCoordsPosLevel ()
 Get the number of coordinates at the position level. More...
 
virtual unsigned int GetNumCoordsVelLevel ()
 Get the number of coordinates at the velocity level. More...
 
virtual unsigned int GetNumConstraints ()
 Get the number of scalar constraints.
 
virtual unsigned int GetNumConstraintsBilateral ()
 Get the number of bilateral scalar constraints.
 
virtual unsigned int GetNumConstraintsUnilateral ()
 Get the number of unilateral scalar constraints.
 
unsigned int GetOffset_x ()
 Get offset in the state vector (position part)
 
unsigned int GetOffset_w ()
 Get offset in the state vector (speed part)
 
unsigned int GetOffset_L ()
 Get offset in the lagrangian multipliers.
 
void SetOffset_x (const unsigned int moff)
 Set offset in the state vector (position part) Note: only the ChSystem::Setup function should use this.
 
void SetOffset_w (const unsigned int moff)
 Set offset in the state vector (speed part) Note: only the ChSystem::Setup function should use this.
 
void SetOffset_L (const unsigned int moff)
 Set offset in the lagrangian multipliers Note: only the ChSystem::Setup function should use this.
 
virtual void IntStateGather (const unsigned int off_x, ChState &x, const unsigned int off_v, ChStateDelta &v, double &T)
 From item's state to global state vectors y={x,v} pasting the states at the specified offsets. More...
 
virtual void IntStateScatter (const unsigned int off_x, const ChState &x, const unsigned int off_v, const ChStateDelta &v, const double T, bool full_update)
 From global state vectors y={x,v} to item's state (and update) fetching the states at the specified offsets. More...
 
virtual void IntStateGatherAcceleration (const unsigned int off_a, ChStateDelta &a)
 From item's state acceleration to global acceleration vector. More...
 
virtual void IntStateScatterAcceleration (const unsigned int off_a, const ChStateDelta &a)
 From global acceleration vector to item's state acceleration. More...
 
virtual void IntStateGatherReactions (const unsigned int off_L, ChVectorDynamic<> &L)
 From item's reaction forces to global reaction vector. More...
 
virtual void IntStateScatterReactions (const unsigned int off_L, const ChVectorDynamic<> &L)
 From global reaction vector to item's reaction forces. More...
 
virtual void IntStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv)
 Computes x_new = x + Dt , using vectors at specified offsets. More...
 
virtual void IntStateGetIncrement (const unsigned int off_x, const ChState &x_new, const ChState &x, const unsigned int off_v, ChStateDelta &Dv)
 Computes Dt = x_new - x, using vectors at specified offsets. More...
 
virtual void IntLoadResidual_F (const unsigned int off, ChVectorDynamic<> &R, const double c)
 Takes the F force term, scale and adds to R at given offset: R += c*F. More...
 
virtual void IntLoadResidual_Mv (const unsigned int off, ChVectorDynamic<> &R, const ChVectorDynamic<> &w, const double c)
 Takes the M*v term, multiplying mass by a vector, scale and adds to R at given offset: R += c*M*w. More...
 
virtual void IntLoadLumpedMass_Md (const unsigned int off, ChVectorDynamic<> &Md, double &err, const double c)
 Adds the lumped mass to a Md vector, representing a mass diagonal matrix. More...
 
virtual void IntLoadResidual_CqL (const unsigned int off_L, ChVectorDynamic<> &R, const ChVectorDynamic<> &L, const double c)
 Takes the term Cq'*L, scale and adds to R at given offset: R += c*Cq'*L. More...
 
virtual void IntLoadConstraint_C (const unsigned int off, ChVectorDynamic<> &Qc, const double c, bool do_clamp, double recovery_clamp)
 Takes the term C, scale and adds to Qc at given offset: Qc += c*C. More...
 
virtual void IntLoadConstraint_Ct (const unsigned int off, ChVectorDynamic<> &Qc, const double c)
 Takes the term Ct, scale and adds to Qc at given offset: Qc += c*Ct. More...
 
virtual void IntToDescriptor (const unsigned int off_v, const ChStateDelta &v, const ChVectorDynamic<> &R, const unsigned int off_L, const ChVectorDynamic<> &L, const ChVectorDynamic<> &Qc)
 Prepare variables and constraints to accommodate a solution: More...
 
virtual void IntFromDescriptor (const unsigned int off_v, ChStateDelta &v, const unsigned int off_L, ChVectorDynamic<> &L)
 After a solver solution, fetch values from variables and constraints into vectors: More...
 
virtual void InjectVariables (ChSystemDescriptor &descriptor)
 Register with the given system descriptor any ChVariable objects associated with this item.
 
virtual void InjectConstraints (ChSystemDescriptor &descriptor)
 Register with the given system descriptor any ChConstraint objects associated with this item.
 
virtual void LoadConstraintJacobians ()
 Compute and load current Jacobians in encapsulated ChConstraint objects.
 
virtual void InjectKRMMatrices (ChSystemDescriptor &descriptor)
 Register with the given system descriptor any ChKRMBlock objects associated with this item.
 
virtual void LoadKRMMatrices (double Kfactor, double Rfactor, double Mfactor)
 Compute and load current stiffnes (K), damping (R), and mass (M) matrices in encapsulated ChKRMBlock objects. More...
 
virtual void VariablesFbReset ()
 Sets the 'fb' part (the known term) of the encapsulated ChVariables to zero.
 
virtual void VariablesFbLoadForces (double factor=1)
 Adds the current forces (applied to item) into the encapsulated ChVariables, in the 'fb' part: qf+=forces*factor.
 
virtual void VariablesQbLoadSpeed ()
 Initialize the 'qb' part of the ChVariables with the current value of speeds. More...
 
virtual void VariablesFbIncrementMq ()
 Adds M*q (masses multiplied current 'qb') to Fb, ex. More...
 
virtual void VariablesQbSetSpeed (double step=0)
 Fetches the item speed (ex. More...
 
virtual void VariablesQbIncrementPosition (double step)
 Increment item positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor. More...
 
virtual void ConstraintsBiReset ()
 Sets to zero the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_C (double factor=1, double recovery_clamp=0.1, bool do_clamp=false)
 Adds the current C (constraint violation) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_Ct (double factor=1)
 Adds the current Ct (partial t-derivative, as in C_dt=0-> [Cq]*q_dt=-Ct) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_Qc (double factor=1)
 Adds the current Qc (the vector of C_dtdt=0 -> [Cq]*q_dtdt=Qc ) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsFbLoadForces (double factor=1)
 Adds the current link-forces, if any, (caused by springs, etc.) to the 'fb' vectors of the ChVariables referenced by encapsulated ChConstraints.
 
virtual void ConstraintsFetch_react (double factor=1)
 Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...
 
virtual void ArchiveOut (ChArchiveOut &archive_out) override
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIn (ChArchiveIn &archive_in) override
 Method to allow deserialization of transient data from archives. More...
 
- Public Member Functions inherited from chrono::ChObj
 ChObj (const ChObj &other)
 
int GetIdentifier () const
 Get the unique integer identifier of this object. More...
 
void SetTag (int tag)
 Set an object integer tag (default: -1). More...
 
int GetTag () const
 Get the tag of this object.
 
void SetName (const std::string &myname)
 Set the name of this object.
 
const std::string & GetName () const
 Get the name of this object.
 
double GetChTime () const
 Gets the simulation time of this object.
 
void SetChTime (double m_time)
 Sets the simulation time of this object.
 
virtual std::string & ArchiveContainerName ()
 

Protected Attributes

ChSystemsystem
 parent system
 
std::shared_ptr< ChVisualModelInstancevis_model_instance
 instantiated visualization model
 
std::vector< std::shared_ptr< ChCamera > > cameras
 set of cameras
 
unsigned int offset_x
 offset in vector of state (position part)
 
unsigned int offset_w
 offset in vector of state (speed part)
 
unsigned int offset_L
 offset in vector of lagrangian multipliers
 
- Protected Attributes inherited from chrono::ChObj
double ChTime
 object simulation time
 
std::string m_name
 object name
 
int m_identifier
 object unique identifier
 
int m_tag
 user-supplied tag
 

Friends

class ChSystem
 
class ChAssembly
 
class modal::ChModalAssembly
 

Additional Inherited Members

- Protected Member Functions inherited from chrono::ChObj
int GenerateUniqueIdentifier ()
 

Member Function Documentation

◆ AddCamera()

void chrono::ChPhysicsItem::AddCamera ( std::shared_ptr< ChCamera camera)

Attach a ChCamera to this physical item.

Multiple cameras can be attached to the same physics item.

◆ AddCollisionModelsToSystem()

virtual void chrono::ChPhysicsItem::AddCollisionModelsToSystem ( ChCollisionSystem coll_sys) const
inlinevirtual

Add to the provided collision system any collision models managed by this physics item.

A derived calss should invoke ChCollisionSystem::Add for each of its collision models.

Reimplemented in chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChBody, and chrono::ChConveyor.

◆ AddVisualModel()

void chrono::ChPhysicsItem::AddVisualModel ( std::shared_ptr< ChVisualModel model)

Add an (optional) visualization model.

Not that an instance of the given visual model is associated with this physics ite, thus allowing sharing the same model among multiple items.

◆ AddVisualShape()

void chrono::ChPhysicsItem::AddVisualShape ( std::shared_ptr< ChVisualShape shape,
const ChFrame<> &  frame = ChFrame<>() 
)

Add the specified visual shape to the visualization model.

If this item does not have a visual model, one is created.

◆ AddVisualShapeFEA()

void chrono::ChPhysicsItem::AddVisualShapeFEA ( std::shared_ptr< ChVisualShapeFEA shapeFEA)

Add the specified FEA visualization object to the visualization model.

If this item does not have a visual model, one is created.

◆ ArchiveIn()

void chrono::ChPhysicsItem::ArchiveIn ( ChArchiveIn archive_in)
overridevirtual

Method to allow deserialization of transient data from archives.

Method to allow de serialization of transient data from archives.

Reimplemented from chrono::ChObj.

Reimplemented in chrono::ChLinkMateRackPinion, chrono::ChLinkMateOrthogonal, chrono::ChLinkMateParallel, chrono::modal::ChModalAssembly, chrono::ChLinkMateDistanceZ, chrono::ChLinkMatePrismatic, chrono::ChParticleCloud, chrono::ChBody, chrono::ChLinkMateRevolute, chrono::ChLinkLockLock, chrono::ChAssembly, chrono::ChLinkMateCylindrical, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChLinkMatePlanar, chrono::ChLinkTSDA, chrono::ChContactContainerNSC, chrono::ChShaftBodyTranslation, chrono::ChLinkLock, chrono::ChLinkLockGear, chrono::ChLinkLockPulley, chrono::ChContactContainerSMC, chrono::ChLinkMarkers, chrono::ChLinkRSDA, chrono::ChLinkMotorLinearDriveline, chrono::ChShaft, chrono::ChLinkMateGeneric, chrono::ChShaftsPlanetary, chrono::fea::ChLinkNodeFace, chrono::ChLinkRevoluteTranslational, chrono::ChLinkRevoluteSpherical, chrono::ChShaftsFreewheel, chrono::fea::ChLinkBeamIGAFrame, chrono::ChLinkMotorRotationDriveline, chrono::fea::ChLinkNodeFrame, chrono::ChLinkDistance, chrono::ChShaftsTorqueConverter, chrono::ChShaftsGearboxAngled, chrono::ChShaftsGearbox, chrono::fea::ChLinkNodeSlopeFrame, chrono::ChConveyor, chrono::ChShaftsClutch, chrono::ChLinkMotionImposed, chrono::ChLink, chrono::ChIndexedParticles, chrono::ChShaftsCouple, chrono::fea::ChLinkNodeNode, chrono::ChLinkBase, chrono::ChLinkUniversal, chrono::ChLoadContainer, chrono::ChLinkLockTrajectory, chrono::ChShaftsMotorPosition, chrono::ChLinkLockClearance, chrono::ChLinkMotorRotation, chrono::ChShaftsMotorSpeed, chrono::ChShaftBodyRotation, chrono::ChBodyAuxRef, chrono::ChFeeder, chrono::ChLinkMotorLinearSpeed, chrono::ChShaftsGear, chrono::ChLinkRevolute, chrono::ChLinkMotorRotationAngle, chrono::ChLinkMotorRotationSpeed, chrono::ChLinkMotorLinear, chrono::ChLinkMotorLinearPosition, chrono::ChShaftsMotor, chrono::ChLinkLockBrake, chrono::ChIndexedNodes, chrono::ChLinkBushing, chrono::ChShaftsThermalEngine, chrono::ChLinkMotor, chrono::ChLinkMotorRotationTorque, chrono::ChShaftsMotorLoad, chrono::ChLinkLockLinActuator, chrono::ChLinkLockPointSpline, chrono::ChLinkLockScrew, chrono::ChLinkMotorLinearForce, chrono::ChShaftsTorque, chrono::ChShaftsTorsionSpring, chrono::ChShaftsAppliedTorque, chrono::ChLinkMate, chrono::ChContactContainer, and chrono::ChProximityContainer.

◆ ConstraintsFetch_react()

virtual void chrono::ChPhysicsItem::ConstraintsFetch_react ( double  factor = 1)
inlinevirtual

Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints.

Mostly used after the solver provided the solution in ChConstraints. Also, should convert the reactions obtained from dynamical simulation, from link space to intuitive react_force and react_torque.

Reimplemented in chrono::fea::ChLinkNodeSlopeFrame, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChAssembly, chrono::ChLinkLock, chrono::ChLinkMateGeneric, chrono::ChContactContainerNSC, chrono::fea::ChLinkNodeFace, chrono::fea::ChLinkBeamIGAFrame, chrono::fea::ChLinkNodeFrame, and chrono::fea::ChLinkNodeNode.

◆ ForceToRest()

virtual void chrono::ChPhysicsItem::ForceToRest ( )
inlinevirtual

Set zero speed (and zero accelerations) in state, without changing the position.

Child classes should implement this function if GetNumCoordsPosLevel() > 0. It is used by owner ChSystem for some static analysis.

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChBody, and chrono::ChShaft.

◆ GetCenter()

void chrono::ChPhysicsItem::GetCenter ( ChVector3d mcenter)
virtual

Get a symbolic 'center' of the object.

By default this function returns the center of the AABB. It could be overridden by child classes, anyway it must always get a point that must be inside AABB.

◆ GetNumCoordsPosLevel()

virtual unsigned int chrono::ChPhysicsItem::GetNumCoordsPosLevel ( )
inlinevirtual

Get the number of coordinates at the position level.

Might differ from coordinates at velocity level if quaternions are used for rotations.

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChAssembly, chrono::ChShaft, chrono::ChBody, chrono::ChExternalDynamics, chrono::fea::ChMesh, chrono::ChConveyor, chrono::ChIndexedParticles, chrono::ChLinkMotorLinearSpeed, and chrono::ChFeeder.

◆ GetNumCoordsVelLevel()

virtual unsigned int chrono::ChPhysicsItem::GetNumCoordsVelLevel ( )
inlinevirtual

Get the number of coordinates at the velocity level.

Might differ from coordinates at position level if quaternions are used for rotations.

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChAssembly, chrono::ChBody, chrono::fea::ChMesh, chrono::ChConveyor, chrono::ChIndexedParticles, and chrono::ChFeeder.

◆ GetNumVisualModelClones()

virtual unsigned int chrono::ChPhysicsItem::GetNumVisualModelClones ( ) const
inlinevirtual

Return the number of clones of the visual model associated with this physics item.

If the visual model is cloned (for example for a physics item modeling a particle system), this function should return the total number of copies of the visual model, including the "original". The current coordinate frame of a given clone can be obtained by calling GetVisualModelFrame() with the corresponding clone identifier.

Reimplemented in chrono::ChIndexedParticles.

◆ GetTotalAABB()

ChAABB chrono::ChPhysicsItem::GetTotalAABB ( )
virtual

Get the entire AABB axis-aligned bounding box of the object.

The AABB must enclose the collision models, if any. By default is infinite AABB. Should be overridden by child classes.

Reimplemented in chrono::ChBody.

◆ GetVisualModel()

std::shared_ptr< ChVisualModel > chrono::ChPhysicsItem::GetVisualModel ( ) const

Access the visualization model (if any).

Note that this model may be shared with other physics items that may instance it. Returns nullptr if no visual model is present.

◆ GetVisualModelFrame()

virtual ChFrame chrono::ChPhysicsItem::GetVisualModelFrame ( unsigned int  nclone = 0) const
inlinevirtual

Get the reference frame (expressed in and relative to the absolute frame) of the visual model.

If the visual model is cloned (for example for a physics item modeling a particle system), this function returns the coordinate system of the specified clone.

Reimplemented in chrono::ChBody, chrono::ChLinkRSDA, chrono::ChLinkMarkers, chrono::ChIndexedParticles, chrono::ChLinkBase, and chrono::ChLinkMateGeneric.

◆ GetVisualShape()

std::shared_ptr< ChVisualShape > chrono::ChPhysicsItem::GetVisualShape ( unsigned int  i) const

Access the specified visualization shape in the visualization model (if any).

Note that no range check is performed.

◆ GetVisualShapeFEA()

std::shared_ptr< ChVisualShapeFEA > chrono::ChPhysicsItem::GetVisualShapeFEA ( unsigned int  i) const

Access the specified FEA visualization object in the visualization model (if any).

Note that no range check is performed.

◆ IntFromDescriptor()

virtual void chrono::ChPhysicsItem::IntFromDescriptor ( const unsigned int  off_v,
ChStateDelta v,
const unsigned int  off_L,
ChVectorDynamic<> &  L 
)
inlinevirtual

After a solver solution, fetch values from variables and constraints into vectors:

Parameters
off_voffset for v
vvector to where the q 'unknowns' term of the variables will be copied
off_Loffset for L
Lvector to where L 'lagrangian ' term of the constraints will be copied

Reimplemented in chrono::modal::ChModalAssembly, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChParticleCloud, chrono::ChAssembly, chrono::ChLinkLock, chrono::fea::ChMesh, chrono::ChLinkMateGeneric, chrono::ChShaft, chrono::ChContactContainerNSC, chrono::fea::ChLinkNodeFace, chrono::fea::ChLinkBeamIGAFrame, chrono::fea::ChLinkNodeFrame, chrono::ChExternalDynamics, chrono::fea::ChLinkNodeSlopeFrame, and chrono::fea::ChLinkNodeNode.

◆ IntLoadConstraint_C()

virtual void chrono::ChPhysicsItem::IntLoadConstraint_C ( const unsigned int  off,
ChVectorDynamic<> &  Qc,
const double  c,
bool  do_clamp,
double  recovery_clamp 
)
inlinevirtual

Takes the term C, scale and adds to Qc at given offset: Qc += c*C.

Parameters
offoffset in Qc residual
Qcresult: the Qc residual, Qc += c*C
ca scaling factor
do_clampapply clamping to c*C?
recovery_clampvalue for min/max clamping of c*C

Reimplemented in chrono::modal::ChModalAssembly, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChAssembly, chrono::ChLinkLock, chrono::ChLinkMateGeneric, chrono::ChContactContainerNSC, chrono::fea::ChLinkNodeFace, chrono::fea::ChLinkBeamIGAFrame, chrono::fea::ChLinkNodeFrame, chrono::fea::ChLinkNodeSlopeFrame, and chrono::fea::ChLinkNodeNode.

◆ IntLoadConstraint_Ct()

virtual void chrono::ChPhysicsItem::IntLoadConstraint_Ct ( const unsigned int  off,
ChVectorDynamic<> &  Qc,
const double  c 
)
inlinevirtual

Takes the term Ct, scale and adds to Qc at given offset: Qc += c*Ct.

Parameters
offoffset in Qc residual
Qcresult: the Qc residual, Qc += c*Ct
ca scaling factor

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChAssembly, chrono::ChLinkLock, and chrono::ChLinkMateGeneric.

◆ IntLoadLumpedMass_Md()

virtual void chrono::ChPhysicsItem::IntLoadLumpedMass_Md ( const unsigned int  off,
ChVectorDynamic<> &  Md,
double &  err,
const double  c 
)
inlinevirtual

Adds the lumped mass to a Md vector, representing a mass diagonal matrix.

Used by lumped explicit integrators. If mass lumping is impossible or approximate, adds scalar error to "error" parameter. Md += c*diag(M)

Parameters
offoffset in Md vector
Mdresult: Md vector, diagonal of the lumped mass matrix
errresult: not touched if lumping does not introduce errors
ca scaling factor

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, chrono::ChExternalDynamics, and chrono::ChLoadContainer.

◆ IntLoadResidual_CqL()

virtual void chrono::ChPhysicsItem::IntLoadResidual_CqL ( const unsigned int  off_L,
ChVectorDynamic<> &  R,
const ChVectorDynamic<> &  L,
const double  c 
)
inlinevirtual

Takes the term Cq'*L, scale and adds to R at given offset: R += c*Cq'*L.

Parameters
off_Loffset in L multipliers
Rresult: the R residual, R += c*Cq'*L
Lthe L vector
ca scaling factor

Reimplemented in chrono::modal::ChModalAssembly, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChAssembly, chrono::ChLinkLock, chrono::ChLinkMateGeneric, chrono::ChContactContainerNSC, chrono::fea::ChLinkNodeFace, chrono::fea::ChLinkBeamIGAFrame, chrono::fea::ChLinkNodeFrame, chrono::fea::ChLinkNodeSlopeFrame, and chrono::fea::ChLinkNodeNode.

◆ IntLoadResidual_F()

virtual void chrono::ChPhysicsItem::IntLoadResidual_F ( const unsigned int  off,
ChVectorDynamic<> &  R,
const double  c 
)
inlinevirtual

Takes the F force term, scale and adds to R at given offset: R += c*F.

Parameters
offoffset in R residual
Rresult: the R residual, R += c*F
ca scaling factor

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, chrono::ChContactContainerSMC, chrono::ChHydraulicActuatorBase, chrono::ChLinkMarkers, chrono::ChExternalDynamics, chrono::ChShaftsTorque, and chrono::ChLoadContainer.

◆ IntLoadResidual_Mv()

virtual void chrono::ChPhysicsItem::IntLoadResidual_Mv ( const unsigned int  off,
ChVectorDynamic<> &  R,
const ChVectorDynamic<> &  w,
const double  c 
)
inlinevirtual

Takes the M*v term, multiplying mass by a vector, scale and adds to R at given offset: R += c*M*w.

Parameters
offoffset in R residual
Rresult: the R residual, R += c*M*v
wthe w vector
ca scaling factor

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, chrono::ChLoadContainer, and chrono::ChExternalDynamics.

◆ IntStateGather()

virtual void chrono::ChPhysicsItem::IntStateGather ( const unsigned int  off_x,
ChState x,
const unsigned int  off_v,
ChStateDelta v,
double &  T 
)
inlinevirtual

From item's state to global state vectors y={x,v} pasting the states at the specified offsets.

Parameters
off_xoffset in x state vector
xstate vector, position part
off_voffset in v state vector
vstate vector, speed part
Ttime

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ IntStateGatherAcceleration()

virtual void chrono::ChPhysicsItem::IntStateGatherAcceleration ( const unsigned int  off_a,
ChStateDelta a 
)
inlinevirtual

From item's state acceleration to global acceleration vector.

Parameters
off_aoffset in a accel. vector
aacceleration part of state vector derivative

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ IntStateGatherReactions()

virtual void chrono::ChPhysicsItem::IntStateGatherReactions ( const unsigned int  off_L,
ChVectorDynamic<> &  L 
)
inlinevirtual

◆ IntStateGetIncrement()

virtual void chrono::ChPhysicsItem::IntStateGetIncrement ( const unsigned int  off_x,
const ChState x_new,
const ChState x,
const unsigned int  off_v,
ChStateDelta Dv 
)
inlinevirtual

Computes Dt = x_new - x, using vectors at specified offsets.

By default, when DOF = DOF_w, it does just the difference of two state vectors, but in some cases (ex when using quaternions for rotations) it could do more complex stuff, and children classes might overload it.

Parameters
off_xoffset in x state vector
x_newstate vector, final position part
xstate vector, initial position part
off_voffset in v state vector
Dvstate vector, increment. Here gets the result

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, and chrono::fea::ChMesh.

◆ IntStateIncrement()

virtual void chrono::ChPhysicsItem::IntStateIncrement ( const unsigned int  off_x,
ChState x_new,
const ChState x,
const unsigned int  off_v,
const ChStateDelta Dv 
)
inlinevirtual

Computes x_new = x + Dt , using vectors at specified offsets.

By default, when DOF = DOF_w, it does just the sum, but in some cases (ex when using quaternions for rotations) it could do more complex stuff, and children classes might overload it.

Parameters
off_xoffset in x state vector
x_newstate vector, position part, incremented result
xstate vector, initial position part
off_voffset in v state vector
Dvstate vector, increment

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, and chrono::fea::ChMesh.

◆ IntStateScatter()

virtual void chrono::ChPhysicsItem::IntStateScatter ( const unsigned int  off_x,
const ChState x,
const unsigned int  off_v,
const ChStateDelta v,
const double  T,
bool  full_update 
)
inlinevirtual

From global state vectors y={x,v} to item's state (and update) fetching the states at the specified offsets.

Parameters
off_xoffset in x state vector
xstate vector, position part
off_voffset in v state vector
vstate vector, speed part
Ttime
full_updateperform complete update

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ IntStateScatterAcceleration()

virtual void chrono::ChPhysicsItem::IntStateScatterAcceleration ( const unsigned int  off_a,
const ChStateDelta a 
)
inlinevirtual

From global acceleration vector to item's state acceleration.

Parameters
off_aoffset in a accel. vector
aacceleration part of state vector derivative

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ IntStateScatterReactions()

virtual void chrono::ChPhysicsItem::IntStateScatterReactions ( const unsigned int  off_L,
const ChVectorDynamic<> &  L 
)
inlinevirtual

◆ IntToDescriptor()

virtual void chrono::ChPhysicsItem::IntToDescriptor ( const unsigned int  off_v,
const ChStateDelta v,
const ChVectorDynamic<> &  R,
const unsigned int  off_L,
const ChVectorDynamic<> &  L,
const ChVectorDynamic<> &  Qc 
)
inlinevirtual

Prepare variables and constraints to accommodate a solution:

Parameters
off_voffset for v and R
vvector copied into the q 'unknowns' term of the variables
Rvector copied into the F 'force' term of the variables
off_Loffset for L and Qc
Lvector copied into the L 'lagrangian ' term of the constraints
Qcvector copied into the Qb 'constraint' term of the constraints

Reimplemented in chrono::modal::ChModalAssembly, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChParticleCloud, chrono::ChAssembly, chrono::ChLinkLock, chrono::fea::ChMesh, chrono::ChLinkMateGeneric, chrono::ChShaft, chrono::ChContactContainerNSC, chrono::fea::ChLinkNodeFace, chrono::fea::ChLinkBeamIGAFrame, chrono::fea::ChLinkNodeFrame, chrono::ChExternalDynamics, chrono::fea::ChLinkNodeSlopeFrame, and chrono::fea::ChLinkNodeNode.

◆ IsCollisionEnabled()

virtual bool chrono::ChPhysicsItem::IsCollisionEnabled ( ) const
inlinevirtual

Tell if the object is subject to collision.

Only for interface; child classes may override this, using internal flags.

Reimplemented in chrono::ChParticleCloud, chrono::fea::ChMesh, chrono::ChConveyor, and chrono::ChBody.

◆ LoadKRMMatrices()

virtual void chrono::ChPhysicsItem::LoadKRMMatrices ( double  Kfactor,
double  Rfactor,
double  Mfactor 
)
inlinevirtual

Compute and load current stiffnes (K), damping (R), and mass (M) matrices in encapsulated ChKRMBlock objects.

The resulting KRM blocks represent linear combinations of the K, R, and M matrices, with the specified coefficients Kfactor, Rfactor,and Mfactor, respectively. Note: signs are flipped from the term dF/dx in the integrator: K = -dF/dq and R = -dF/dv.

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChLinkMateGeneric, chrono::ChContactContainerSMC, chrono::ChExternalDynamics, chrono::ChLinkMotionImposed, chrono::ChLoadContainer, and chrono::ChLinkMotorRotationAngle.

◆ RemoveCollisionModelsFromSystem()

virtual void chrono::ChPhysicsItem::RemoveCollisionModelsFromSystem ( ChCollisionSystem coll_sys) const
inlinevirtual

Remove from the provided collision system any collision models managed by this physics item.

A derived class should invoke ChCollisionSystem::Remove for each of its collision models.

Reimplemented in chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChBody, and chrono::ChConveyor.

◆ SetSystem()

void chrono::ChPhysicsItem::SetSystem ( ChSystem m_system)
virtual

Set the pointer to the parent ChSystem().

Also add to new collision system / remove from old collision system.

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChAssembly, chrono::ChLinkMotorLinearDriveline, chrono::ChLinkMotorRotationDriveline, and chrono::ChConveyor.

◆ Update() [1/2]

virtual void chrono::ChPhysicsItem::Update ( bool  update_assets = true)
inlinevirtual

As above, but does not require updating of time-dependent data.

By default, calls Update(mytime) using item's current time.

Reimplemented in chrono::modal::ChModalAssembly, chrono::ChParticleCloud, chrono::ChBody, chrono::ChAssembly, chrono::ChLink, and chrono::ChBodyAuxRef.

◆ Update() [2/2]

void chrono::ChPhysicsItem::Update ( double  mytime,
bool  update_assets = true 
)
virtual

This is an important function, which is called by the owner ChSystem at least once per integration step.

It may update all auxiliary data of the item, such as matrices if any, etc., depending on the current coordinates. The inherited classes, for example the ChLinkMask, often implement specialized versions of this Update(time) function, because they might need to update inner states, forces, springs, etc. This base version, by default, simply updates the item's time, and update the asset tree, if any.

Reimplemented in chrono::ChLinkMatePlanar, chrono::ChHydraulicActuatorBase, chrono::ChLinkRevoluteTranslational, chrono::ChLinkRevoluteSpherical, chrono::ChExternalDynamics, chrono::ChParticleCloud, chrono::ChBody, chrono::fea::ChLinkNodeFaceRot, chrono::fea::ChLinkNodeFrameGeneric, chrono::ChAssembly, chrono::ChLinkLock, chrono::ChShaft, chrono::ChLinkMarkers, chrono::fea::ChLinkNodeFace, chrono::fea::ChLinkBeamIGAFrame, chrono::fea::ChLinkNodeFrame, chrono::ChShaftsTorqueConverter, chrono::fea::ChLinkNodeSlopeFrame, chrono::fea::ChLinkNodeNode, chrono::ChLink, chrono::ChShaftsTorque, chrono::ChLoadContainer, chrono::ChLinkMotorRotation, chrono::ChLinkMotorLinear, chrono::ChLinkMotor, chrono::ChLinkMateOrthogonal, chrono::ChLinkMateDistanceZ, chrono::ChLinkMateGeneric, chrono::ChContactContainerNSC, chrono::ChContactContainerSMC, and chrono::fea::ChMesh.

◆ VariablesFbIncrementMq()

virtual void chrono::ChPhysicsItem::VariablesFbIncrementMq ( )
inlinevirtual

Adds M*q (masses multiplied current 'qb') to Fb, ex.

if qb is initialized with v_old using VariablesQbLoadSpeed, this method can be used in timestepping schemes that do: M*v_new = M*v_old + forces*dt

Reimplemented in chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ VariablesQbIncrementPosition()

virtual void chrono::ChPhysicsItem::VariablesQbIncrementPosition ( double  step)
inlinevirtual

Increment item positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor.

pos+=qb*step If qb is a speed, this behaves like a single step of 1-st order numerical integration (Euler integration).

Reimplemented in chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ VariablesQbLoadSpeed()

virtual void chrono::ChPhysicsItem::VariablesQbLoadSpeed ( )
inlinevirtual

Initialize the 'qb' part of the ChVariables with the current value of speeds.

Note: since 'qb' is the unknown, this function seems unnecessary, unless used before VariablesFbIncrementMq()

Reimplemented in chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.

◆ VariablesQbSetSpeed()

virtual void chrono::ChPhysicsItem::VariablesQbSetSpeed ( double  step = 0)
inlinevirtual

Fetches the item speed (ex.

linear and angular vel.in rigid bodies) from the 'qb' part of the ChVariables and sets it as the current item speed. If 'step' is not 0, also should compute the approximate acceleration of the item using backward differences, that is accel=(new_speed-old_speed)/step. Mostly used after the solver provided the solution in ChVariables.

Reimplemented in chrono::ChParticleCloud, chrono::ChAssembly, chrono::fea::ChMesh, chrono::ChShaft, and chrono::ChExternalDynamics.


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono/physics/ChPhysicsItem.h
  • /builds/uwsbel/chrono/src/chrono/physics/ChPhysicsItem.cpp