chrono::ChLoadXYZnodeBody Class Referenceabstract


Base class for loads representing a concentrated force acting between a ChNodeXYZ and a ChBody Users should inherit from this and implement a custom ComputeForce(), this is enough to have the load working.

Note: there are already some predefined examples, ie. children classes with common concrete implementations, such as ChLoadXYZnodeBodySpring ChLoadXYZnodeBodyBushing etc.; take inspiration from those example to inherit your own load if they are not enough.

#include <ChLoadsXYZnode.h>

Inheritance diagram for chrono::ChLoadXYZnodeBody:
Collaboration diagram for chrono::ChLoadXYZnodeBody:

Public Member Functions

 ChLoadXYZnodeBody (std::shared_ptr< ChNodeXYZ > nodeA, std::shared_ptr< ChBody > bodyB)
virtual void ComputeForce (const ChFrameMoving<> &rel_AB, ChVector<> &loc_force)=0
 Compute the force on the nodeA, in local coordsystem of SetApplicationFrameB (the
ChVector GetForce () const
 For diagnosis purposes, this can return the actual last computed value of the applied force, expressed in coordinate system of loc_application_B, assumed applied to node.
void SetApplicationFrameB (const ChFrame<> &mpB)
 Set the application frame of bushing on bodyB.
ChFrame GetApplicationFrameB () const
ChFrameMoving GetAbsoluteFrameB () const
 Get absolute coordinate of frame B (last computed)
std::shared_ptr< ChNodeXYZGetNodeA () const
std::shared_ptr< ChBodyGetBodyB () const
- Public Member Functions inherited from chrono::ChLoadCustomMultiple
 ChLoadCustomMultiple (std::vector< std::shared_ptr< ChLoadable >> &mloadables)
 ChLoadCustomMultiple (std::shared_ptr< ChLoadable > mloadableA, std::shared_ptr< ChLoadable > mloadableB)
 ChLoadCustomMultiple (std::shared_ptr< ChLoadable > mloadableA, std::shared_ptr< ChLoadable > mloadableB, std::shared_ptr< ChLoadable > mloadableC)
virtual int LoadGet_ndof_x () override
 Gets the number of DOFs affected by this load (position part)
virtual int LoadGet_ndof_w () override
 Gets the number of DOFs affected by this load (speed part)
virtual void LoadGetStateBlock_x (ChState &mD) override
 Gets all the current DOFs packed in a single vector (position part)
virtual void LoadGetStateBlock_w (ChStateDelta &mD) override
 Gets all the current DOFs packed in a single vector (speed part)
virtual void LoadStateIncrement (const ChState &x, const ChStateDelta &dw, ChState &x_new) override
 Increment a packed state (ex. More...
virtual int LoadGet_field_ncoords () override
 Number of coordinates in the interpolated field, ex=3 for a tetrahedron finite element or a cable, = 1 for a thermal problem, etc.
virtual void ComputeJacobian (ChState *state_x, ChStateDelta *state_w, ChMatrixRef mK, ChMatrixRef mR, ChMatrixRef mM) override
 Compute jacobians (default fallback). More...
virtual void LoadIntLoadResidual_F (ChVectorDynamic<> &R, const double c) override
 Adds the internal loads Q (pasted at global nodes offsets) into a global vector R, multiplied by a scaling factor c, as R += forces * c.
virtual void CreateJacobianMatrices () override
 Create the jacobian loads if needed, and also set the ChVariables referenced by the sparse KRM block.
virtual ChVectorDynamicGetQ ()
 Access the generalized load vector Q.
- Public Member Functions inherited from chrono::ChLoadBase
ChLoadJacobiansGetJacobians ()
 Access the jacobians (if any, i.e. if this is a stiff load)
virtual void Update (double time)
 Update: this is called at least at each time step. More...
virtual bool IsStiff ()=0
 Report if this is load is stiff. More...
virtual void InjectKRMmatrices (ChSystemDescriptor &mdescriptor)
 Tell to a system descriptor that there are item(s) of type ChKblock in this object (for further passing it to a solver) Basically does nothing, but inherited classes must specialize this.
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)
virtual ChObjClone () const =0
 "Virtual" copy constructor. More...
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)
virtual void ArchiveOUT (ChArchiveOut &marchive)
 Method to allow serialization of transient data to archives.
virtual void ArchiveIN (ChArchiveIn &marchive)
 Method to allow de-serialization of transient data from archives.
virtual std::string & ArchiveContainerName ()

Protected Member Functions

virtual void ComputeQ (ChState *state_x, ChStateDelta *state_w) override
 Compute Q, the generalized load. More...

Protected Attributes

ChFrame loc_application_B
 application point on body B (local)
ChVector computed_loc_force
 store computed values here
ChFrameMoving frame_Aw
 for results
ChFrameMoving frame_Bw
 for results
- Protected Attributes inherited from chrono::ChLoadBase
- Protected Attributes inherited from chrono::ChObj
double ChTime
 the time of simulation for the object

Additional Inherited Members

- Public Attributes inherited from chrono::ChLoadCustomMultiple
std::vector< std::shared_ptr< ChLoadable > > loadables
ChVectorDynamic load_Q

Constructor & Destructor Documentation

◆ ChLoadXYZnodeBody()

chrono::ChLoadXYZnodeBody::ChLoadXYZnodeBody ( std::shared_ptr< ChNodeXYZ nodeA,
std::shared_ptr< ChBody bodyB 

Member Function Documentation

◆ ComputeForce()

virtual void chrono::ChLoadXYZnodeBody::ComputeForce ( const ChFrameMoving<> &  rel_AB,
ChVector<> &  loc_force 
pure virtual

Compute the force on the nodeA, in local coordsystem of SetApplicationFrameB (the

auxiliary frame attached to body) given relative position of nodeA respect to B Body will receive the reaction force. Inherited classes MUST IMPLEMENT THIS.

Implemented in chrono::ChLoadXYZnodeBodyBushing, and chrono::ChLoadXYZnodeBodySpring.

◆ ComputeQ()

void chrono::ChLoadXYZnodeBody::ComputeQ ( ChState state_x,
ChStateDelta state_w 

Compute Q, the generalized load.

It calls ComputeBodyBodyForceTorque, so in children classes you do not need to implement it. Called automatically at each Update().

state_xstate position to evaluate Q
state_wstate speed to evaluate Q

Implements chrono::ChLoadBase.