Description

Generic mate constraint, where one can select which DOFs must be constrained between two frames attached to the two bodies.

#include <ChLinkMate.h>

Inheritance diagram for chrono::ChLinkMateGeneric:
Collaboration diagram for chrono::ChLinkMateGeneric:

Public Member Functions

 ChLinkMateGeneric (bool mc_x=true, bool mc_y=true, bool mc_z=true, bool mc_rx=true, bool mc_ry=true, bool mc_rz=true)
 
 ChLinkMateGeneric (const ChLinkMateGeneric &other)
 
virtual ChLinkMateGenericClone () const override
 "Virtual" copy constructor (covariant return type).
 
virtual ChCoordsys GetLinkRelativeCoords () override
 Get the link coordinate system, expressed relative to Body2 (the 'master' body). More...
 
virtual ChFrame GetAssetsFrame (unsigned int nclone=0) override
 Get the master coordinate system for the assets (this will return the absolute coordinate system of the 'master' marker2)
 
ChFrameGetFrame1 ()
 Access the coordinate system considered attached to body1. More...
 
ChFrameGetFrame2 ()
 Access the coordinate system considered attached to body1. More...
 
bool IsConstrainedX ()
 
bool IsConstrainedY ()
 
bool IsConstrainedZ ()
 
bool IsConstrainedRx ()
 
bool IsConstrainedRy ()
 
bool IsConstrainedRz ()
 
void SetConstrainedCoords (bool mc_x, bool mc_y, bool mc_z, bool mc_rx, bool mc_ry, bool mc_rz)
 Sets which movements (of frame 1 respect to frame 2) are constrained.
 
virtual void Initialize (std::shared_ptr< ChBodyFrame > mbody1, std::shared_ptr< ChBodyFrame > mbody2, bool pos_are_relative, ChFrame<> mframe1, ChFrame<> mframe2)
 Specialized initialization for generic mate, given the two bodies to be connected, the positions of the two frames to connect on the bodies (each expressed in body or abs. More...
 
virtual void Initialize (std::shared_ptr< ChBodyFrame > mbody1, std::shared_ptr< ChBodyFrame > mbody2, bool pos_are_relative, ChVector<> mpt1, ChVector<> mpt2, ChVector<> mnorm1, ChVector<> mnorm2)
 Initialization based on passing two vectors (point + dir) on the two bodies, they will represent the X axes of the two frames (Y and Z will be built from the X vector via Gram Schmidt orthonormalization). More...
 
virtual void Update (double mtime, bool update_assets=true) override
 Override all time, jacobian etc. updating.
 
virtual int RestoreRedundant () override
 If some constraint is redundant, return to normal state.
 
virtual void SetDisabled (bool mdis) override
 User can use this to enable/disable all the constraint of the link as desired. More...
 
virtual void SetBroken (bool mon) override
 Ex:3rd party software can set the 'broken' status via this method.
 
virtual int GetDOC () override
 Get the number of scalar constraints, if any, in this item.
 
virtual int GetDOC_c () override
 Get the number of scalar constraints, if any, in this item (only bilateral constr.) Children classes might override this. More...
 
virtual int GetDOC_d () override
 Get the number of scalar constraints, if any, in this item (only unilateral constr.) Children classes might override this. More...
 
virtual void IntStateGatherReactions (const unsigned int off_L, ChVectorDynamic<> &L) override
 From item's reaction forces to global reaction vector.
 
virtual void IntStateScatterReactions (const unsigned int off_L, const ChVectorDynamic<> &L) override
 From global reaction vector to item's reaction forces.
 
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.
 
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.
 
virtual void IntLoadConstraint_Ct (const unsigned int off, ChVectorDynamic<> &Qc, const double c) override
 Takes the term Ct, scale and adds to Qc at given offset: Qc += c*Ct.
 
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:
 
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:
 
virtual void InjectConstraints (ChSystemDescriptor &mdescriptor) override
 Tell to a system descriptor that there are constraints of type ChConstraint in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this. More...
 
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 ConstraintsLoadJacobians () override
 Adds the current jacobians in encapsulated ChConstraints.
 
virtual void ConstraintsFetch_react (double factor=1) override
 Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...
 
virtual void ArchiveOUT (ChArchiveOut &marchive) override
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIN (ChArchiveIn &marchive) override
 Method to allow deserialization of transient data from archives. 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() and also add to new collision system / remove from old coll.system.
 
void AddAsset (std::shared_ptr< ChAsset > masset)
 Add an optional asset (it can be used to define visualization shapes, es ChSphereShape, or textures, or custom attached properties that the user can define by creating his class inherited from ChAsset)
 
std::vector< std::shared_ptr< ChAsset > > & GetAssets ()
 Access to the list of optional assets.
 
std::shared_ptr< ChAssetGetAssetN (unsigned int num)
 Access the Nth asset in the list of optional assets.
 
virtual unsigned int GetAssetsFrameNclones ()
 Optionally, a ChPhysicsItem can return multiple asset coordinate systems; this can be helpful if, for example, when a ChPhysicsItem contains 'clones' with the same assets (ex. More...
 
virtual bool GetCollide () const
 Tell if the object is subject to collision. More...
 
virtual void SyncCollisionModels ()
 If this physical item contains one or more collision models, synchronize their coordinates and bounding boxes to the state of the item. More...
 
virtual void AddCollisionModelsToSystem ()
 If this physical item contains one or more collision models, add them to the system's collision engine. More...
 
virtual void RemoveCollisionModelsFromSystem ()
 If this physical item contains one or more collision models, remove them from the system's collision engine. More...
 
virtual void GetTotalAABB (ChVector<> &bbmin, ChVector<> &bbmax)
 Get the entire AABB axis-aligned bounding box of the object. More...
 
virtual void GetCenter (ChVector<> &mcenter)
 Get a symbolic 'center' of the object. More...
 
virtual void StreamINstate (ChStreamInBinary &mstream)
 Method to deserialize only the state (position, speed) Must be implemented by child classes. More...
 
virtual void StreamOUTstate (ChStreamOutBinary &mstream)
 Method to serialize only the state (position, speed) Must be implemented by child classes. 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 SetNoSpeedNoAcceleration ()
 Set zero speed (and zero accelerations) in state, without changing the position. More...
 
virtual int GetDOF ()
 Get the number of scalar coordinates (variables), if any, in this item. More...
 
virtual int GetDOF_w ()
 Get the number of scalar coordinates of variables derivatives (usually = DOF, but might be different than DOF, ex. More...
 
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)
 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 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 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 InjectVariables (ChSystemDescriptor &mdescriptor)
 Tell to a system descriptor that there are variables of type ChVariables in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this. 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.
 
virtual void InjectKRMmatrices (ChSystemDescriptor &mdescriptor)
 Tell to a system descriptor that there are items of type ChKblock in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this. More...
 
virtual void KRMmatricesLoad (double Kfactor, double Rfactor, double Mfactor)
 Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any. More...
 
- Public Member Functions inherited from chrono::ChObj
 ChObj (const ChObj &other)
 
int GetIdentifier () const
 Gets the numerical identifier of the object.
 
void SetIdentifier (int id)
 Sets the numerical identifier of the object.
 
double GetChTime () const
 Gets the simulation time of this object.
 
void SetChTime (double m_time)
 Sets the simulation time of this object.
 
const char * GetName () const
 Gets the name of the object as C Ascii null-terminated string -for reading only!
 
void SetName (const char myname[])
 Sets the name of this object, as ascii string.
 
std::string GetNameString () const
 Gets the name of the object as C Ascii null-terminated string.
 
void SetNameString (const std::string &myname)
 Sets the name of this object, as std::string.
 
void MFlagsSetAllOFF (int &mflag)
 
void MFlagsSetAllON (int &mflag)
 
void MFlagSetON (int &mflag, int mask)
 
void MFlagSetOFF (int &mflag, int mask)
 
int MFlagGet (int &mflag, int mask)
 

Protected Member Functions

void SetupLinkMask ()
 
void ChangedLinkMask ()
 

Protected Attributes

ChFrame frame1
 
ChFrame frame2
 
bool c_x
 
bool c_y
 
bool c_z
 
bool c_rx
 
bool c_ry
 
bool c_rz
 
int ndoc
 number of DOC, degrees of constraint
 
int ndoc_c
 number of DOC, degrees of constraint (only bilaterals)
 
int ndoc_d
 number of DOC, degrees of constraint (only unilaterals)
 
ChLinkMaskmask
 
ChMatrixC
 residuals
 
- Protected Attributes inherited from chrono::ChPhysicsItem
ChSystemsystem
 parent system
 
std::vector< std::shared_ptr< ChAsset > > assets
 set of assets
 
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
 the time of simulation for the object
 

Member Function Documentation

void chrono::ChLinkMateGeneric::ArchiveIN ( ChArchiveIn marchive)
overridevirtual

Method to allow deserialization of transient data from archives.

Method to allow de serialization of transient data from archives.

Reimplemented from chrono::ChLinkMate.

Reimplemented in chrono::ChLinkMateOrthogonal, chrono::ChLinkMateParallel, chrono::ChLinkMateXdistance, chrono::ChLinkMateCoaxial, chrono::ChLinkMatePlane, and chrono::ChLinkRackpinion.

void chrono::ChLinkMateGeneric::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.

virtual int chrono::ChLinkMateGeneric::GetDOC_c ( )
overridevirtual

Get the number of scalar constraints, if any, in this item (only bilateral constr.) Children classes might override this.

Reimplemented from chrono::ChPhysicsItem.

virtual int chrono::ChLinkMateGeneric::GetDOC_d ( )
overridevirtual

Get the number of scalar constraints, if any, in this item (only unilateral constr.) Children classes might override this.

Reimplemented from chrono::ChPhysicsItem.

ChFrame& chrono::ChLinkMateGeneric::GetFrame1 ( )

Access the coordinate system considered attached to body1.

Its position is expressed in the coordinate system of body1.

ChFrame& chrono::ChLinkMateGeneric::GetFrame2 ( )

Access the coordinate system considered attached to body1.

Its position is expressed in the coordinate system of body1.

virtual ChCoordsys chrono::ChLinkMateGeneric::GetLinkRelativeCoords ( )
overridevirtual

Get the link coordinate system, expressed relative to Body2 (the 'master' body).

This represents the 'main' reference of the link: reaction forces are expressed in this coordinate system. (It is the coordinate system of the contact plane relative to Body2)

Reimplemented from chrono::ChLink.

void chrono::ChLinkMateGeneric::Initialize ( std::shared_ptr< ChBodyFrame mbody1,
std::shared_ptr< ChBodyFrame mbody2,
bool  pos_are_relative,
ChFrame<>  mframe1,
ChFrame<>  mframe2 
)
virtual

Specialized initialization for generic mate, given the two bodies to be connected, the positions of the two frames to connect on the bodies (each expressed in body or abs.

coordinates).

Parameters
mbody1first body to link
mbody2second body to link
pos_are_relativetrue: following pos. are relative to bodies.
mframe1mate frame (slave), for 1st body (rel. or abs., see flag above)
mframe2mate frame (master), for 2nd body (rel. or abs., see flag above)
void chrono::ChLinkMateGeneric::Initialize ( std::shared_ptr< ChBodyFrame mbody1,
std::shared_ptr< ChBodyFrame mbody2,
bool  pos_are_relative,
ChVector<>  mpt1,
ChVector<>  mpt2,
ChVector<>  mnorm1,
ChVector<>  mnorm2 
)
virtual

Initialization based on passing two vectors (point + dir) on the two bodies, they will represent the X axes of the two frames (Y and Z will be built from the X vector via Gram Schmidt orthonormalization).

Use the other ChLinkMateGeneric::Initialize() if you want to set the two frames directly.

Parameters
mbody1first body to link
mbody2second body to link
pos_are_relativetrue: following pos. are relative to bodies.
mpt1origin of slave frame 1, for 1st body (rel. or abs., see flag above)
mpt2origin of master frame 2, for 2nd body (rel. or abs., see flag above)
mnorm1X axis of slave plane, for 1st body (rel. or abs., see flag above)
mnorm2X axis of master plane, for 2nd body (rel. or abs., see flag above)

Reimplemented in chrono::ChLinkMateOrthogonal, chrono::ChLinkMateParallel, chrono::ChLinkMateCoaxial, and chrono::ChLinkMatePlane.

void chrono::ChLinkMateGeneric::InjectConstraints ( ChSystemDescriptor mdescriptor)
overridevirtual

Tell to a system descriptor that there are constraints of type ChConstraint in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this.

Reimplemented from chrono::ChPhysicsItem.

void chrono::ChLinkMateGeneric::SetDisabled ( bool  mdis)
overridevirtual

User can use this to enable/disable all the constraint of the link as desired.

Reimplemented from chrono::ChLinkBase.