chrono::ChLoadBodyForce Class Reference

Description

Load representing a concentrated force acting on a rigid body.

The force can rotate together with the body (if in body local coordinates) or not. The application point can follow the body (if in body local coordinates) or not. The magnitude of the applied force can be optionally modulated by a function of time. The default modulation is the constant function with value 1.

#include <ChLoadsBody.h>

Inheritance diagram for chrono::ChLoadBodyForce:
Collaboration diagram for chrono::ChLoadBodyForce:

Public Member Functions

 ChLoadBodyForce (std::shared_ptr< ChBody > body, const ChVector<> &force, bool local_force, const ChVector<> &point, bool local_point=true)
 
virtual ChLoadBodyForceClone () const override
 "Virtual" copy constructor (covariant return type).
 
void SetForce (const ChVector<> &force, bool is_local)
 Set the constant force vector. More...
 
ChVector GetForce () const
 Return the current force vector (scaled by the current modulation value).
 
void SetApplicationPoint (const ChVector<> &point, const bool is_local)
 Set the application point of force, assumed to be constant. More...
 
ChVector GetApplicationPoint () const
 Return the location of the application point.
 
void SetModulationFunction (std::shared_ptr< ChFunction > modulation)
 Set modulation function. More...
 
virtual void ComputeQ (ChState *state_x, ChStateDelta *state_w) override
 Compute Q, the generalized load. More...
 
- 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 ()
 

Additional Inherited Members

- Public Attributes inherited from chrono::ChLoadCustom
std::shared_ptr< ChLoadableloadable
 
ChVectorDynamic load_Q
 
- Protected Attributes inherited from chrono::ChLoadBase
ChLoadJacobiansjacobians
 
- Protected Attributes inherited from chrono::ChObj
double ChTime
 the time of simulation for the object
 

Constructor & Destructor Documentation

◆ ChLoadBodyForce()

chrono::ChLoadBodyForce::ChLoadBodyForce ( std::shared_ptr< ChBody body,
const ChVector<> &  force,
bool  local_force,
const ChVector<> &  point,
bool  local_point = true 
)
Parameters
bodyobject to apply load to
forceforce to apply
local_forceforce is in body local coords
pointapplication point for the force
local_pointapplication point is in body local coords

Member Function Documentation

◆ ComputeQ()

void chrono::ChLoadBodyForce::ComputeQ ( ChState state_x,
ChStateDelta state_w 
)
overridevirtual

Compute Q, the generalized load.

Called automatically at each Update().

Parameters
state_xstate position to evaluate Q
state_wstate speed to evaluate Q

Implements chrono::ChLoadBase.

◆ SetApplicationPoint()

void chrono::ChLoadBodyForce::SetApplicationPoint ( const ChVector<> &  point,
const bool  is_local 
)

Set the application point of force, assumed to be constant.

It can be expressed in absolute coordinates or body local coordinates

◆ SetForce()

void chrono::ChLoadBodyForce::SetForce ( const ChVector<> &  force,
bool  is_local 
)

Set the constant force vector.

It can be expressed in absolute coordinates or body local coordinates. This value is optionally modulated by a function of time.

◆ SetModulationFunction()

void chrono::ChLoadBodyForce::SetModulationFunction ( std::shared_ptr< ChFunction modulation)
inline

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.


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