chrono::ChGenericConstraint Class Reference

Description

Class for basic algebraic constraints (not to be confused with ChLink objects, which are complex kinematical constraints between rigid bodies in 3D, containing ChConstraint objects)

This is the base data for algebraic constraints. The base implemetation is basically useless unless it has some inherited implementation (see other classes below)

Child classes should implement at least Update() RestoreReferences() Get_Cn().

#include <ChGenericConstraint.h>

Inheritance diagram for chrono::ChGenericConstraint:
Collaboration diagram for chrono::ChGenericConstraint:

Public Member Functions

virtual bool IsValid ()
 Tells if the constraint data is currently valid. More...
 
virtual bool IsDisabled ()
 Tells if the constraint is currently turned on or off by the user.
 
virtual void SetDisabled (bool mon)
 
virtual bool IsActive ()
 Tells if the constraint is currently active, in general, that is tells if it must be included into the system solver or not. More...
 
virtual ChMatrixGet_C ()
 Returns the matrix of residuals (a column vector with Cn elements) If constraint is not active, returns NULL because no equations can be used. More...
 
virtual int Get_Cn ()
 —TO IMPLEMENT– w.overriding Returns the number of equations in this constraints (the size of the C residual vector)
 
virtual int Reset_Cn (int mCn)
 Changes the number of equations in this constraints (reset the size of the C residual vector). More...
 
virtual bool RestoreReferences ()
 —TO IMPLEMENT– w.overloading This may be overloaded by child classes. More...
 
virtual bool Update ()
 —TO IMPLEMENT– w.overloading This MUST be overloaded by child classes. More...
 

Protected Attributes

bool valid
 
bool disabled
 
int Cn
 constraints equations in this constraint
 
ChMatrixC
 residual matrix
 

Member Function Documentation

virtual ChMatrix* chrono::ChGenericConstraint::Get_C ( )
virtual

Returns the matrix of residuals (a column vector with Cn elements) If constraint is not active, returns NULL because no equations can be used.

virtual bool chrono::ChGenericConstraint::IsActive ( )
virtual

Tells if the constraint is currently active, in general, that is tells if it must be included into the system solver or not.

virtual bool chrono::ChGenericConstraint::IsValid ( )
virtual

Tells if the constraint data is currently valid.

Instead of implementing it, child classes may simply set valif=false (or true) depending on the result of their implementations of RestoreReference();

int chrono::ChGenericConstraint::Reset_Cn ( int  mCn)
virtual

Changes the number of equations in this constraints (reset the size of the C residual vector).

virtual bool chrono::ChGenericConstraint::RestoreReferences ( )
virtual

—TO IMPLEMENT– w.overloading This may be overloaded by child classes.

Argument should be the 'database' where the reference restoring takes place. Should return false if referencing was not possible. Should set valid=true/false depending on referencing success.

virtual bool chrono::ChGenericConstraint::Update ( )
virtual

—TO IMPLEMENT– w.overloading This MUST be overloaded by child classes.

It should compute the residuals (vector 'C') of the constraint equations, where C=0 is for satisfied constraints. Should return false if updating was not possible.

Reimplemented in chrono::ChGenericConstraint_Chf_VertDistance, chrono::ChGenericConstraint_Chf_HorDistance, chrono::ChGenericConstraint_Chf_Continuity, and chrono::ChGenericConstraint_Chf_ImposeVal.