chrono::fea::ChLinkNodeFrameGeneric Class Reference

Description

Constraint between an FEA node of ChNodeFEAxyz type and a ChBodyFrame (frame) object.

The node position is constrained to a given coordinate system CSYS that moves with the ChBodyFrame. The movements of the node respect to X, Y, Z axes of such CSYS can be costrained or not, depending on three boolean toggles. By default, XYZ are all constrained and the node follows the center of CSYS, s it is completely locked to it, but other options are, for example, that you just enable the X constraint (so the node moves on the flat YZ plane) or you just enable XY constraints (so the node moves along the Z direction), etc.

#include <ChLinkNodeFrame.h>

Inheritance diagram for chrono::fea::ChLinkNodeFrameGeneric:
Collaboration diagram for chrono::fea::ChLinkNodeFrameGeneric:

Public Member Functions

 ChLinkNodeFrameGeneric (bool mc_x=true, bool mc_y=true, bool mc_z=true)
 
 ChLinkNodeFrameGeneric (const ChLinkNodeFrameGeneric &other)
 
virtual ChLinkNodeFrameGenericClone () const override
 "Virtual" copy constructor (covariant return type).
 
virtual unsigned int GetNumAffectedCoords () override
 Get the number of scalar variables affected by constraints in this link.
 
virtual unsigned int GetNumConstraintsBilateral () override
 Number of scalar constraints.
 
virtual ChVectorDynamic GetConstraintViolation () const override
 Get the current constraint violations.
 
bool IsConstrainedX ()
 
bool IsConstrainedY ()
 
bool IsConstrainedZ ()
 
void SetConstrainedCoords (bool mc_x, bool mc_y, bool mc_z)
 Sets which movements (of frame 1 respect to frame 2) are constrained.
 
ChFrame GetFrameNodeAbs () const
 Return the link frame, expressed in absolute coordinates.
 
virtual int Initialize (std::shared_ptr< ChNodeFEAxyz > node, std::shared_ptr< ChBodyFrame > body, ChVector3d *pos=0)
 Initialize this constraint, given the node and body frame to join. More...
 
virtual int Initialize (std::shared_ptr< ChNodeFEAxyz > node, std::shared_ptr< ChBodyFrame > body, chrono::ChCoordsys<> csys_abs)
 Initialize this constraint, given the node and body frame to join. More...
 
std::shared_ptr< fea::ChNodeFEAxyzGetConstrainedNode ()
 Get the connected xyz node (point).
 
std::shared_ptr< ChBodyFrameGetConstrainedBodyFrame ()
 Get the connected body (frame).
 
const ChVector3dGetAttachPosition () const
 Get the attachment position, in the coordinates of the body.
 
const ChCoordsysGetAttachReference () const
 Get the attachment reference, in the coordinates of the body.
 
void SetAttachPositionInBodyCoords (const ChVector3d &pos_loc)
 Set the attachment position, expressed in the coordinates of the body. More...
 
void SetAttachPositionInAbsoluteCoords (const ChVector3d &pos_abs)
 Set the attachment position, expressed in absolute coordinates. More...
 
void SetAttachReferenceInBodyCoords (const ChCoordsys<> &csys_loc)
 Set the attachment reference, expressed in the coordinates of the body. More...
 
void SetAttachReferenceInAbsoluteCoords (const ChCoordsys<> &csys_abs)
 Set the attachment position, expressed in absolute coordinates. More...
 
ChVector3d GetReactionOnNode () const
 Get the reaction force on the node, expressed in the link coordinate system.
 
ChVector3d GetReactionOnBody () const
 Get the reaction force on the body, at the attachment point, expressed in the link coordinate system.
 
virtual void Update (double mytime, bool update_assets=true) override
 Update all auxiliary data of the gear transmission at given time.
 
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.
 
virtual void IntStateGatherReactions (const unsigned int off_L, ChVectorDynamic<> &L) override
 From item's reaction forces to global reaction vector. More...
 
virtual void IntStateScatterReactions (const unsigned int off_L, const ChVectorDynamic<> &L) override
 From global reaction vector to item's reaction forces. More...
 
virtual void IntLoadResidual_CqL (const unsigned int off_L, ChVectorDynamic<> &R, const ChVectorDynamic<> &L, const double c) override
 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) override
 Takes the term C, scale and adds to Qc at given offset: Qc += c*C. 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) override
 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) override
 After a solver solution, fetch values from variables and constraints into vectors: More...
 
virtual void InjectConstraints (ChSystemDescriptor &descriptor) override
 Register with the given system descriptor any ChConstraint objects associated with this item.
 
virtual void ConstraintsBiReset () override
 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) override
 Adds the current C (constraint violation) to the known term (b_i) of encapsulated ChConstraints.
 
virtual void ConstraintsBiLoad_Ct (double factor=1) override
 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 LoadConstraintJacobians () override
 Compute and load current Jacobians in encapsulated ChConstraint objects.
 
virtual void ConstraintsFetch_react (double factor=1) override
 Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...
 
- Public Member Functions inherited from chrono::ChPhysicsItem
 ChPhysicsItem (const ChPhysicsItem &other)
 
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 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 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 () const
 Get the axis-aligned bounding box (AABB) of this object. More...
 
virtual ChVector3d GetCenter () const
 Get a symbolic 'center' of the object. More...
 
virtual void Setup ()
 Perform setup operations. More...
 
virtual void Update (bool update_assets=true)
 Perform an update using the current time.
 
void UpdateVisualModel ()
 Utility function to update only the associated visual assets (if any).
 
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 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 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 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 InjectVariables (ChSystemDescriptor &descriptor)
 Register with the given system descriptor any ChVariable objects associated with this item.
 
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 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.
 
- 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 ()
 

Additional Inherited Members

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

Member Function Documentation

◆ ConstraintsFetch_react()

void chrono::fea::ChLinkNodeFrameGeneric::ConstraintsFetch_react ( double  factor = 1)
overridevirtual

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 from chrono::ChPhysicsItem.

◆ Initialize() [1/2]

int chrono::fea::ChLinkNodeFrameGeneric::Initialize ( std::shared_ptr< ChNodeFEAxyz node,
std::shared_ptr< ChBodyFrame body,
chrono::ChCoordsys<>  csys_abs 
)
virtual

Initialize this constraint, given the node and body frame to join.

The constraint frame is a coordinate system passed with the csys parameter, where csys is expressed in absolute coordinates

Parameters
nodexyz node (point) to join
bodybody (frame) to join
csys_absattachment position in absolute coordinates

◆ Initialize() [2/2]

int chrono::fea::ChLinkNodeFrameGeneric::Initialize ( std::shared_ptr< ChNodeFEAxyz node,
std::shared_ptr< ChBodyFrame body,
ChVector3d pos = 0 
)
virtual

Initialize this constraint, given the node and body frame to join.

The attachment position is the actual position of the node (unless otherwise defined, using the optional 'pos' parameter). Note: the node and body must belong to the same ChSystem.

Parameters
nodexyz node (point) to join
bodybody (frame) to join
posattachment position in absolute coordinates

◆ IntFromDescriptor()

void chrono::fea::ChLinkNodeFrameGeneric::IntFromDescriptor ( const unsigned int  off_v,
ChStateDelta v,
const unsigned int  off_L,
ChVectorDynamic<> &  L 
)
overridevirtual

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 from chrono::ChPhysicsItem.

◆ IntLoadConstraint_C()

void chrono::fea::ChLinkNodeFrameGeneric::IntLoadConstraint_C ( const unsigned int  off,
ChVectorDynamic<> &  Qc,
const double  c,
bool  do_clamp,
double  recovery_clamp 
)
overridevirtual

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 from chrono::ChPhysicsItem.

◆ IntLoadResidual_CqL()

void chrono::fea::ChLinkNodeFrameGeneric::IntLoadResidual_CqL ( const unsigned int  off_L,
ChVectorDynamic<> &  R,
const ChVectorDynamic<> &  L,
const double  c 
)
overridevirtual

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 from chrono::ChPhysicsItem.

◆ IntStateGatherReactions()

void chrono::fea::ChLinkNodeFrameGeneric::IntStateGatherReactions ( const unsigned int  off_L,
ChVectorDynamic<> &  L 
)
overridevirtual

From item's reaction forces to global reaction vector.

Parameters
off_Loffset in L vector
LL vector of reaction forces

Reimplemented from chrono::ChPhysicsItem.

◆ IntStateScatterReactions()

void chrono::fea::ChLinkNodeFrameGeneric::IntStateScatterReactions ( const unsigned int  off_L,
const ChVectorDynamic<> &  L 
)
overridevirtual

From global reaction vector to item's reaction forces.

Parameters
off_Loffset in L vector
LL vector of reaction forces

Reimplemented from chrono::ChPhysicsItem.

◆ IntToDescriptor()

void chrono::fea::ChLinkNodeFrameGeneric::IntToDescriptor ( const unsigned int  off_v,
const ChStateDelta v,
const ChVectorDynamic<> &  R,
const unsigned int  off_L,
const ChVectorDynamic<> &  L,
const ChVectorDynamic<> &  Qc 
)
overridevirtual

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 from chrono::ChPhysicsItem.

◆ SetAttachPositionInAbsoluteCoords()

void chrono::fea::ChLinkNodeFrameGeneric::SetAttachPositionInAbsoluteCoords ( const ChVector3d pos_abs)
inline

Set the attachment position, expressed in absolute coordinates.

This function may be called only after initialization.

◆ SetAttachPositionInBodyCoords()

void chrono::fea::ChLinkNodeFrameGeneric::SetAttachPositionInBodyCoords ( const ChVector3d pos_loc)
inline

Set the attachment position, expressed in the coordinates of the body.

This function may be called only after initialization.

◆ SetAttachReferenceInAbsoluteCoords()

void chrono::fea::ChLinkNodeFrameGeneric::SetAttachReferenceInAbsoluteCoords ( const ChCoordsys<> &  csys_abs)
inline

Set the attachment position, expressed in absolute coordinates.

This function may be called only after initialization.

◆ SetAttachReferenceInBodyCoords()

void chrono::fea::ChLinkNodeFrameGeneric::SetAttachReferenceInBodyCoords ( const ChCoordsys<> &  csys_loc)
inline

Set the attachment reference, expressed in the coordinates of the body.

This function may be called only after initialization.


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