chrono::ChLoadXYZnodeForceAbsolute Class Reference


Load representing a concentrated force acting on a ChNodeXYZ.

The force can be constant or optionally modulated with time.

#include <ChLoadsXYZnode.h>

Inheritance diagram for chrono::ChLoadXYZnodeForceAbsolute:
Collaboration diagram for chrono::ChLoadXYZnodeForceAbsolute:

Public Member Functions

 ChLoadXYZnodeForceAbsolute (std::shared_ptr< ChNodeXYZ > node, const ChVector<> &force)
virtual ChLoadXYZnodeForceAbsoluteClone () const override
 "Virtual" copy constructor (covariant return type).
virtual void ComputeForce (const ChVector<> &abs_pos, const ChVector<> &abs_vel, ChVector<> &abs_force) override
 Compute the force on the node, in absolute coordsystem, given position of node as abs_pos.
void SetForceBase (const ChVector<> &force)
 Set the applied force vector (expressed in absolute coordinates). More...
ChVector GetForce () const
 Return the current force vector (scaled by the current modulation value).
void SetModulationFunction (std::shared_ptr< ChFunction > modulation)
 Set modulation function. More...
- Public Member Functions inherited from chrono::ChLoadXYZnodeForce
 ChLoadXYZnodeForce (std::shared_ptr< ChNodeXYZ > node)
virtual void ComputeQ (ChState *state_x, ChStateDelta *state_w) override
 Compute Q, the generalized load. More...
ChVector GetForce () const
 For diagnosis purposes, this can return the actual last computed value of the applied force, expressed in absolute coordinate system, assumed applied to node.
- Public Member Functions inherited from chrono::ChLoadCustom
 ChLoadCustom (std::shared_ptr< ChLoadable > mloadable)
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, 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 LoadIntLoadResidual_Mv (ChVectorDynamic<> &R, const ChVectorDynamic<> &w, double c) override
 Default fallback: compute jacobians via ComputeJacobian(), then use M=-dQ/da to do R += c*M*w. More...
virtual void LoadIntLoadLumpedMass_Md (ChVectorDynamic<> &Md, double &err, const double c) override
 If possible, override this to bypass jacobian computation, if analytical expression of lumped mass is known. More...
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 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)
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)
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 bool IsStiff () override
 Inherited classes could override this and return true, if the load benefits from a jacobian when using implicit integrators.
virtual void Update (double time) override
 Update: this is called at least at each time step. More...

Protected Attributes

ChVector m_force_base
 base force value
std::shared_ptr< ChFunctionm_modulation
 modulation function of time
double m_scale
 scaling factor (current modulation value)
- Protected Attributes inherited from chrono::ChLoadXYZnodeForce
ChVector computed_abs_force
- 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::ChLoadCustom
std::shared_ptr< ChLoadableloadable
ChVectorDynamic load_Q

Constructor & Destructor Documentation

◆ ChLoadXYZnodeForceAbsolute()

chrono::ChLoadXYZnodeForceAbsolute::ChLoadXYZnodeForceAbsolute ( std::shared_ptr< ChNodeXYZ node,
const ChVector<> &  force 
nodenode to apply load to
forceforce to apply, assumed in absolute coordsys,

Member Function Documentation

◆ SetForceBase()

void chrono::ChLoadXYZnodeForceAbsolute::SetForceBase ( const ChVector<> &  force)

Set the applied force vector (expressed in absolute coordinates).

The force is assumed constant, unless a scaling time function is provided.

◆ SetModulationFunction()

void chrono::ChLoadXYZnodeForceAbsolute::SetModulationFunction ( std::shared_ptr< ChFunction modulation)

Set modulation function.

This is a function of time which (optionally) modulates the specified applied force. By default the modulation is a constant function, always returning a value of 1.

◆ Update()

void chrono::ChLoadXYZnodeForceAbsolute::Update ( double  time)

Update: this is called at least at each time step.

  • It recomputes the generalized load Q vector(s)
  • It recomputes the jacobian(s) K,R,M in case of stiff load Q and jacobians assumed evaluated at the current state. Jacobian structures are automatically allocated if needed.

Reimplemented from chrono::ChLoadXYZnodeForce.

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