chrono::ChConstraintRollingNormal Class Reference

Description

Normal rolling contact constraint between two objects, each represented by a tuple of ChVariables objects.

#include <ChConstraintRollingNormal.h>

Inheritance diagram for chrono::ChConstraintRollingNormal:
Collaboration diagram for chrono::ChConstraintRollingNormal:

Public Member Functions

 ChConstraintRollingNormal (const ChConstraintRollingNormal &other)
 
virtual ChConstraintRollingNormalClone () const override
 "Virtual" copy constructor (covariant return type).
 
ChConstraintRollingNormaloperator= (const ChConstraintRollingNormal &other)
 Assignment operator.
 
float GetRollingFrictionCoefficient ()
 Get the rolling friction coefficient.
 
void SetRollingFrictionCoefficient (float mcoeff)
 Set the rolling friction coefficient.
 
float GetSpinningFrictionCoefficient ()
 Get the spinning friction coefficient.
 
void SetSpinningFrictionCoefficient (float mcoeff)
 Set the spinning friction coefficient.
 
ChConstraintRollingTangentialGetRollingConstraintU ()
 Get pointer to U tangential component.
 
ChConstraintRollingTangentialGetRollingConstraintV ()
 Get pointer to V tangential component.
 
ChConstraintContactNormalGetNormalConstraint ()
 Get pointer to normal contact component.
 
void SetRollingConstraintU (ChConstraintRollingTangential *mconstr)
 Set pointer to U tangential component.
 
void SetRollingConstraintV (ChConstraintRollingTangential *mconstr)
 Set pointer to V tangential component.
 
void SetNormalConstraint (ChConstraintContactNormal *mconstr)
 Set pointer to normal contact component.
 
virtual void Project () override
 Project the value of a possible 'l_i' value of constraint reaction onto admissible set. More...
 
- Public Member Functions inherited from chrono::ChConstraintTwoTuples
 ChConstraintTwoTuples (const ChConstraintTwoTuples &other)
 
ChConstraintTwoTuplesoperator= (const ChConstraintTwoTuples &other)
 Assignment operator: copy from other object.
 
ChConstraintTupleTupleA ()
 Access tuple a.
 
ChConstraintTupleTupleB ()
 Access tuple b.
 
void SetTuples (ChConstraintTuple *tupleA, ChConstraintTuple *tupleB)
 Set the two tuples.
 
void SetTuplesFromContactables (ChContactable *objA, ChContactable *objB)
 Set the two tuples from two contactable objects.
 
virtual void UpdateAuxiliary () override
 This function updates the following auxiliary data: More...
 
virtual double ComputeJacobianTimesState () override
 Compute the product between the Jacobian of this constraint, [Cq_i], and the vector of variables. More...
 
virtual void IncrementState (double deltal) override
 Increment the vector of variables with the quantity [invM]*[Cq_i]'*deltal. More...
 
virtual void AddJacobianTimesVectorInto (double &result, ChVectorConstRef vect) const override
 Add the product of the corresponding block in the system matrix by 'vect' and add to result. More...
 
virtual void AddJacobianTransposedTimesScalarInto (ChVectorRef result, double l) const override
 Add the product of the corresponding transposed block in the system matrix by 'l' and add to result. More...
 
virtual void PasteJacobianInto (ChSparseMatrix &mat, unsigned int start_row, unsigned int start_col) const override
 Write the constraint Jacobian into the specified global matrix at the offsets of the associated variables. More...
 
virtual void PasteJacobianTransposedInto (ChSparseMatrix &mat, unsigned int start_row, unsigned int start_col) const override
 Write the transposed constraint Jacobian into the specified global matrix at the offsets of the associated variables. More...
 
- Public Member Functions inherited from chrono::ChConstraint
 ChConstraint (const ChConstraint &other)
 
ChConstraintoperator= (const ChConstraint &other)
 Assignment operator: copy from other object.
 
bool operator== (const ChConstraint &other) const
 Comparison (compares only flags, not the Jacobians).
 
bool IsValid () const
 Indicate if the constraint data is currently valid.
 
void SetValid (bool mon)
 Set the "valid" state of this constraint.
 
bool IsDisabled () const
 Indicate if the constraint is currently turned on or off.
 
void SetDisabled (bool mon)
 
bool IsRedundant () const
 Indicate if the constraint is redundant or singular.
 
void SetRedundant (bool mon)
 Mark the constraint as redundant.
 
bool IsBroken () const
 Indicate if the constraint is broken, due to excess pulling/pushing.
 
void SetBroken (bool mon)
 Set the constraint as broken. More...
 
virtual bool IsUnilateral () const
 Indicate if the constraint is unilateral (typical complementarity constraint).
 
virtual bool IsLinear () const
 Indicate if the constraint is linear.
 
Mode GetMode () const
 Get the mode of the constraint. More...
 
void SetMode (Mode mmode)
 Set the mode of the constraint.
 
bool IsActive () const
 Indicate whether the constraint is currently active. More...
 
void SetActive (bool isactive)
 Set the status of the constraint to active.
 
virtual double ComputeResidual ()
 Compute the residual of the constraint using the linear expression. More...
 
double GetResidual () const
 Return the residual of this constraint.
 
void SetRightHandSide (const double mb)
 Sets the known term b_i in [Cq_i]*q + b_i = 0, where: c_i = [Cq_i]*q + b_i = 0.
 
double GetRightHandSide () const
 Return the known term b_i in [Cq_i]*q + b_i = 0, where: c_i= [Cq_i]*q + b_i = 0.
 
void SetComplianceTerm (const double mcfm)
 Set the constraint force mixing term (default=0). More...
 
double GetComplianceTerm () const
 Return the constraint force mixing term.
 
void SetLagrangeMultiplier (double ml_i)
 Set the value of the corresponding Lagrange multiplier (constraint reaction).
 
double GetLagrangeMultiplier () const
 Return the corresponding Lagrange multiplier (constraint reaction).
 
double GetSchurComplement () const
 Return the 'g_i' product, that is [Cq_i]*[invM_i]*[Cq_i]' (+cfm)
 
void SetSchurComplement (double m_g_i)
 Usually you should not use the SetSchurComplement function, because g_i should be automatically computed during the UpdateAuxiliary() .
 
virtual double Violation (double mc_i)
 Return the constraint violation. More...
 
void SetOffset (unsigned int off)
 Set offset in global q vector (set automatically by ChSystemDescriptor)
 
unsigned int GetOffset () const
 Get offset in global q vector.
 
virtual void ArchiveOut (ChArchiveOut &archive_out)
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIn (ChArchiveIn &archive_in)
 Method to allow de-serialization of transient data from archives.
 

Protected Attributes

float rollingfriction
 the rolling friction coefficient
 
float spinningfriction
 the spinning friction coefficient
 
ChConstraintContactNormalconstraint_N
 the pointer to N component
 
ChConstraintRollingTangentialconstraint_U
 the pointer to U tangential component
 
ChConstraintRollingTangentialconstraint_V
 the pointer to V tangential component
 
- Protected Attributes inherited from chrono::ChConstraintTwoTuples
ChConstraintTupletuple_a
 
ChConstraintTupletuple_b
 
- Protected Attributes inherited from chrono::ChConstraint
double c_i
 constraint residual (if satisfied, c must be 0)
 
double l_i
 Lagrange multiplier (reaction)
 
double b_i
 right-hand side term in [Cq_i]*q+b_i=0 , note: c_i= [Cq_i]*q + b_i
 
double cfm_i
 Constraint force mixing if needed to add some numerical 'compliance' in the constraint. More...
 
Mode mode
 mode of the constraint
 
double g_i
 product [Cq_i]*[invM_i]*[Cq_i]' (+cfm)
 
unsigned int offset
 offset in global "l" state vector (needed by some solvers)
 

Additional Inherited Members

- Public Types inherited from chrono::ChConstraint
enum  Mode { Mode::FREE, Mode::LOCK, Mode::UNILATERAL, Mode::FRICTION }
 Constraint mode. More...
 

Member Function Documentation

◆ Project()

void chrono::ChConstraintRollingNormal::Project ( )
overridevirtual

Project the value of a possible 'l_i' value of constraint reaction onto admissible set.

This projection onto the friction cone will also modify the l_i values of the two tangential friction constraints.

Reimplemented from chrono::ChConstraint.


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