chrono::ChAssembly Class Reference

Description

Class for assemblies of items, for example ChBody, ChLink, ChMesh, etc.

Note that an assembly can be added to another assembly, to create a tree-like hierarchy. All positions of rigid bodies, FEA nodes, etc. are assumed respect to the absolute position.

#include <ChAssembly.h>

Inheritance diagram for chrono::ChAssembly:
Collaboration diagram for chrono::ChAssembly:

Classes

class  IteratorBodies
 Iterator to scan through the list of all ChBody items. More...
 
class  IteratorLinks
 Iterator to scan through the list of all ChLink items. More...
 
class  IteratorOtherPhysicsItems
 Iterator to scan through the list of all physics items (other than bodies or links). More...
 
class  IteratorPhysicsItems
 Iterator to scan through ALL physics items (bodies, links, 'other' physics items, contact container). More...
 

Public Member Functions

 ChAssembly (const ChAssembly &other)
 
virtual ChAssemblyClone () const override
 "Virtual" copy constructor (covariant return type).
 
void Clear ()
 Removes all inserted items: bodies, links, etc.
 
virtual void AddBody (std::shared_ptr< ChBody > newbody)
 Attach a body to this system. Must be an object of exactly ChBody class.
 
virtual void AddLink (std::shared_ptr< ChLink > newlink)
 Attach a link to this system. Must be an object of ChLink or derived classes.
 
virtual void AddOtherPhysicsItem (std::shared_ptr< ChPhysicsItem > newitem)
 Attach a ChPhysicsItem object that is not a body or link.
 
void Add (std::shared_ptr< ChPhysicsItem > newitem)
 Attach whatever type of ChPhysicsItem (ex a ChBody, or a ChParticles, or a ChLink, etc.) to the system. More...
 
void AddBatch (std::shared_ptr< ChPhysicsItem > newitem)
 Items added in this way are added like in the Add() method, but not instantly, they are simply queued in a batch of 'to add' items, that are added automatically at the first Setup() call. More...
 
void FlushBatch ()
 If some items are queued for addition in system, using AddBatch(), this will effectively add them and clean the batch. More...
 
virtual void RemoveBody (std::shared_ptr< ChBody > mbody)
 Remove a body from this system.
 
virtual void RemoveLink (std::shared_ptr< ChLink > mlink)
 Remove a link from this system.
 
virtual void RemoveOtherPhysicsItem (std::shared_ptr< ChPhysicsItem > mitem)
 Remove a ChPhysicsItem object that is not a body or a link.
 
void Remove (std::shared_ptr< ChPhysicsItem > newitem)
 Remove whatever type of ChPhysicsItem that was added to the system. More...
 
void RemoveAllBodies ()
 Remove all bodies from this system.
 
void RemoveAllLinks ()
 Remove all links from this system.
 
void RemoveAllOtherPhysicsItems ()
 Remove all physics items that were not added to body or link lists.
 
IteratorBodies IterBeginBodies ()
 Get a ChBody iterator, initialized at the beginning of body list.
 
IteratorBodies IterEndBodies ()
 
IteratorLinks IterBeginLinks ()
 Get a ChLink iterator, initialized at the beginning of link list.
 
IteratorLinks IterEndLinks ()
 
IteratorOtherPhysicsItems IterBeginOtherPhysicsItems ()
 Get a ChPhysics iterator, initialized at the beginning of additional ChPhysicsItems.
 
IteratorOtherPhysicsItems IterEndOtherPhysicsItems ()
 
IteratorPhysicsItems IterBeginPhysicsItems ()
 Get a ChPhysics iterator.
 
IteratorPhysicsItems IterEndPhysicsItems ()
 
std::vector< std::shared_ptr
< ChBody > > * 
Get_bodylist ()
 Gets the list of children bodies -low level function-. More...
 
std::vector< std::shared_ptr
< ChLink > > * 
Get_linklist ()
 Gets the list of children links -low level function-. More...
 
std::vector< std::shared_ptr
< ChPhysicsItem > > * 
Get_otherphysicslist ()
 Gets the list of children physics items that are not in the body or link lists. More...
 
std::shared_ptr< ChBodySearchBody (const char *m_name)
 Searches a body from its ChObject name.
 
std::shared_ptr< ChLinkSearchLink (const char *m_name)
 Searches a link from its ChObject name.
 
std::shared_ptr< ChPhysicsItemSearchOtherPhysicsItem (const char *m_name)
 Searches from other ChPhysics items (not bodies or links) from name.
 
std::shared_ptr< ChPhysicsItemSearch (const char *m_name)
 Searches whatever item (body, link or other ChPhysics items)
 
std::shared_ptr< ChMarkerSearchMarker (const char *m_name)
 Searches a marker from its ChObject name.
 
std::shared_ptr< ChMarkerSearchMarker (int markID)
 Searches a marker from its unique ID.
 
int GetNbodies () const
 Gets the number of active bodies (so, excluding those that are sleeping or are fixed to ground)
 
int GetNbodiesSleeping () const
 Gets the number of bodies that are in sleeping mode (excluding fixed bodies).
 
int GetNbodiesFixed () const
 Gets the number of bodies that are fixed to ground.
 
int GetNbodiesTotal () const
 Gets the total number of bodies added to the system, including the grounded and sleeping bodies.
 
int GetNlinks () const
 Gets the number of links .
 
int GetNphysicsItems () const
 Gets the number of other physics items (not ChLinks or ChBodies).
 
int GetNcoords () const
 Gets the number of coordinates (considering 7 coords for rigid bodies because of the 4 dof of quaternions)
 
int GetNdof () const
 Gets the number of degrees of freedom of the system.
 
int GetNdoc () const
 Gets the number of scalar constraints added to the system, including constraints on quaternion norms.
 
int GetNsysvars () const
 Gets the number of system variables (coordinates plus the constraint multipliers, in case of quaternions)
 
int GetNcoords_w () const
 Gets the number of coordinates (considering 6 coords for rigid bodies, 3 transl.+3rot.)
 
int GetNdoc_w () const
 Gets the number of scalar constraints added to the system.
 
int GetNdoc_w_C () const
 Gets the number of scalar constraints added to the system (only bilaterals)
 
int GetNdoc_w_D () const
 Gets the number of scalar constraints added to the system (only unilaterals)
 
int GetNsysvars_w () const
 Gets the number of system variables (coordinates plus the constraint multipliers)
 
virtual void SetSystem (ChSystem *m_system) override
 Set the pointer to the parent ChSystem() and also add to new collision system / remove from old coll.system.
 
virtual void SyncCollisionModels () override
 If this physical item contains one or more collision models, sinchronize their coordinates and bounding boxes to the state of the item. More...
 
virtual void Setup () override
 Counts the number of bodies and links. More...
 
virtual void Update (double mytime, bool update_assets=true) override
 Updates all the auxiliary data and children of bodies, forces, links, given their current state. More...
 
virtual void Update (bool update_assets=true) override
 Updates all the auxiliary data and children of bodies, forces, links, given their current state. More...
 
virtual void SetNoSpeedNoAcceleration () override
 Set zero speed (and zero accelerations) in state, without changing the position.
 
virtual int GetDOF () override
 Get the number of scalar coordinates (ex. dim of position vector)
 
virtual int GetDOF_w () override
 Get the number of scalar coordinates of variables derivatives (ex. dim of speed vector)
 
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.)
 
virtual int GetDOC_d () override
 Get the number of scalar constraints, if any, in this item (only unilateral constr.)
 
virtual void IntStateGather (const unsigned int off_x, ChState &x, const unsigned int off_v, ChStateDelta &v, double &T) override
 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) override
 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) override
 From item's state acceleration to global acceleration vector.
 
virtual void IntStateScatterAcceleration (const unsigned int off_a, const ChStateDelta &a) override
 From global acceleration vector to item's state acceleration.
 
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 IntStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv) override
 Computes x_new = x + Dt , using vectors at specified offsets. More...
 
virtual void IntLoadResidual_F (const unsigned int off, ChVectorDynamic<> &R, const double c) override
 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) override
 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 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 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. 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 for a solution: From a vector R into the F 'force' term of the variables From a vector Qc into the Qb 'constraint' term of the constraints From a vector v into the q 'unknowns' term of the variables (for warm starting) From a vector L into the L 'lagrangian ' term of the constraints (for warm starting) 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: To a vector v from the q 'unknowns' term of the variables To a vector L from the L 'lagrangian ' term of the constraints. More...
 
virtual void InjectVariables (ChSystemDescriptor &mdescriptor) override
 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 InjectConstraints (ChSystemDescriptor &mdescriptor) override
 Tell to a system descriptor that there are contraints 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 ConstraintsLoadJacobians () override
 Adds the current jacobians in encapsulated ChConstraints.
 
virtual void InjectKRMmatrices (ChSystemDescriptor &mdescriptor) override
 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) override
 Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any. More...
 
virtual void VariablesFbReset () override
 Sets the 'fb' part (the known term) of the encapsulated ChVariables to zero.
 
virtual void VariablesFbLoadForces (double factor=1) override
 Adds the current forces (applied to item) into the encapsulated ChVariables, in the 'fb' part: qf+=forces*factor.
 
virtual void VariablesQbLoadSpeed () override
 Initialize the 'qb' part of the ChVariables with the current value of speeds. More...
 
virtual void VariablesFbIncrementMq () override
 Adds M*q (masses multiplied current 'qb') to Fb, ex. More...
 
virtual void VariablesQbSetSpeed (double step=0) override
 Fetches the item speed (ex. More...
 
virtual void VariablesQbIncrementPosition (double step) override
 Increment item positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor. 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 ConstraintsBiLoad_Qc (double factor=1) override
 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) override
 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) override
 Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...
 
void ShowHierarchy (ChStreamOutAscii &m_file, int level=0)
 Writes the hierarchy of contained bodies, markers, etc. 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.
 
- Public Member Functions inherited from chrono::ChPhysicsItem
 ChPhysicsItem (const ChPhysicsItem &other)
 
ChSystemGetSystem () const
 Get the pointer to the parent ChSystem()
 
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 ChFrame GetAssetsFrame (unsigned int nclone=0)
 Get the master coordinate system for assets that have some geometric meaning. More...
 
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 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...
 
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.
 
- 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 Attributes

std::vector< std::shared_ptr
< ChBody > > 
bodylist
 list of rigid bodies
 
std::vector< std::shared_ptr
< ChLink > > 
linklist
 list of joints (links)
 
std::vector< std::shared_ptr
< ChPhysicsItem > > 
otherphysicslist
 list of other physic objects that are not bodies or links
 
std::vector< std::shared_ptr
< ChPhysicsItem > > 
batch_to_insert
 list of items to insert when doing Setup() or Flush.
 
int nbodies
 number of bodies (currently active)
 
int nlinks
 number of links
 
int nphysicsitems
 number of other physics items
 
int ncoords
 number of scalar coordinates (including 4th dimension of quaternions) for all active bodies
 
int ndoc
 number of scalar costraints (including constr. on quaternions)
 
int nsysvars
 number of variables (coords+lagrangian mult.), i.e. = ncoords+ndoc for all active bodies
 
int ncoords_w
 number of scalar coordinates when using 3 rot. dof. per body; for all active bodies
 
int ndoc_w
 number of scalar costraints when using 3 rot. dof. per body; for all active bodies
 
int nsysvars_w
 number of variables when using 3 rot. dof. per body; i.e. = ncoords_w+ndoc_w
 
int ndof
 number of degrees of freedom, = ncoords-ndoc = ncoords_w-ndoc_w ,
 
int ndoc_w_C
 number of scalar costraints C, when using 3 rot. dof. per body (excluding unilaterals)
 
int ndoc_w_D
 number of scalar costraints D, when using 3 rot. dof. per body (only unilaterals)
 
int nbodies_sleep
 number of bodies that are sleeping
 
int nbodies_fixed
 number of bodies that are fixed
 
- 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::ChAssembly::Add ( std::shared_ptr< ChPhysicsItem newitem)

Attach whatever type of ChPhysicsItem (ex a ChBody, or a ChParticles, or a ChLink, etc.) to the system.

It will take care of adding it to the proper list: of bodies, of links, or of other generic physic item. (i.e. it calls AddBody(), AddLink() or AddOtherPhysicsItem() ). Note, you cannot call Add() during an Update (ie. items like particle generators that are already inserted in thesystem cannot call this) because not thread safe: rather use AddBatch().

void chrono::ChAssembly::AddBatch ( std::shared_ptr< ChPhysicsItem newitem)

Items added in this way are added like in the Add() method, but not instantly, they are simply queued in a batch of 'to add' items, that are added automatically at the first Setup() call.

This is thread safe.

void chrono::ChAssembly::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.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::FlushBatch ( )

If some items are queued for addition in system, using AddBatch(), this will effectively add them and clean the batch.

Called automatically at each Setup().

std::vector<std::shared_ptr<ChBody> >* chrono::ChAssembly::Get_bodylist ( )

Gets the list of children bodies -low level function-.

NOTE! use this list only to enumerate etc., but NOT to remove or add items (use the appropriate Remove.. and Add.. functions instead!)

std::vector<std::shared_ptr<ChLink> >* chrono::ChAssembly::Get_linklist ( )

Gets the list of children links -low level function-.

NOTE! use this list only to enumerate etc., but NOT to remove or add items (use the appropriate Remove.. and Add.. functions instead!)

std::vector<std::shared_ptr<ChPhysicsItem> >* chrono::ChAssembly::Get_otherphysicslist ( )

Gets the list of children physics items that are not in the body or link lists.

NOTE! use this list only to enumerate etc., but NOT to remove or add items (use the appropriate Remove.. and Add.. functions instead!)

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

Tell to a system descriptor that there are contraints 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.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::InjectKRMmatrices ( ChSystemDescriptor mdescriptor)
overridevirtual

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.

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::InjectVariables ( ChSystemDescriptor mdescriptor)
overridevirtual

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.

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::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: To a vector v from the q 'unknowns' term of the variables To a vector L from the L 'lagrangian ' term of the constraints.

Parameters
off_voffset in v
off_Loffset in L

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::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.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::IntLoadConstraint_Ct ( const unsigned int  off,
ChVectorDynamic<> &  Qc,
const double  c 
)
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::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.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::IntLoadResidual_F ( const unsigned int  off,
ChVectorDynamic<> &  R,
const double  c 
)
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::IntLoadResidual_Mv ( const unsigned int  off,
ChVectorDynamic<> &  R,
const ChVectorDynamic<> &  w,
const double  c 
)
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::IntStateGather ( const unsigned int  off_x,
ChState x,
const unsigned int  off_v,
ChStateDelta v,
double &  T 
)
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::IntStateIncrement ( const unsigned int  off_x,
ChState x_new,
const ChState x,
const unsigned int  off_v,
const ChStateDelta Dv 
)
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::IntStateScatter ( const unsigned int  off_x,
const ChState x,
const unsigned int  off_v,
const ChStateDelta v,
const double  T 
)
overridevirtual

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

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::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 for a solution: From a vector R into the F 'force' term of the variables From a vector Qc into the Qb 'constraint' term of the constraints From a vector v into the q 'unknowns' term of the variables (for warm starting) From a vector L into the L 'lagrangian ' term of the constraints (for warm starting)

Parameters
off_voffset in v, R
off_Loffset in L, Qc

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::KRMmatricesLoad ( double  Kfactor,
double  Rfactor,
double  Mfactor 
)
overridevirtual

Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any.

The K, R, M matrices are added with scaling values Kfactor, Rfactor, Mfactor. NOTE: signs are flipped respect to the ChTimestepper dF/dx terms: K = -dF/dq, R = -dF/dv

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::Remove ( std::shared_ptr< ChPhysicsItem newitem)

Remove whatever type of ChPhysicsItem that was added to the system.

(suggestion: use this instead of old RemoveBody(), RemoveLink, etc.)

void chrono::ChAssembly::Setup ( )
overridevirtual

Counts the number of bodies and links.

Computes the offsets of object states in the global state. Assumes that this->offset_x this->offset_w this->offset_L are already set as starting point for offsetting all the contained sub objects.

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::ShowHierarchy ( ChStreamOutAscii m_file,
int  level = 0 
)

Writes the hierarchy of contained bodies, markers, etc.

in ASCII readable form, mostly for debugging purposes. Level is the tab spacing at the left.

void chrono::ChAssembly::SyncCollisionModels ( )
overridevirtual

If this physical item contains one or more collision models, sinchronize their coordinates and bounding boxes to the state of the item.

Reimplemented from chrono::ChPhysicsItem.

void chrono::ChAssembly::Update ( double  mytime,
bool  update_assets = true 
)
overridevirtual

Updates all the auxiliary data and children of bodies, forces, links, given their current state.

Reimplemented from chrono::ChPhysicsItem.

void chrono::ChAssembly::Update ( bool  update_assets = true)
overridevirtual

Updates all the auxiliary data and children of bodies, forces, links, given their current state.

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::VariablesFbIncrementMq ( )
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::VariablesQbIncrementPosition ( double  step)
overridevirtual

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 (Eulero integration).

Reimplemented from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::VariablesQbLoadSpeed ( )
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.

void chrono::ChAssembly::VariablesQbSetSpeed ( double  step = 0)
overridevirtual

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 from chrono::ChPhysicsItem.

Reimplemented in chrono::ChSystem.