Description

Class for defining a torsional spring-damper between two 1D parts.

This supersedes the old ChShaftsTorsionSpring (which cannot handle extremely stiff spring values).

#include <ChShaftsLoads.h>

Inheritance diagram for chrono::ChShaftsTorsionSpringDamper:

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Collaboration diagram for chrono::ChShaftsTorsionSpringDamper:

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Public Member Functions
	ChShaftsTorsionSpringDamper (std::shared_ptr< ChShaft > shaft1, std::shared_ptr< ChShaft > shaft2, const double stiffness, const double damping)

virtual ChShaftsTorsionSpringDamper *	Clone () const override
	"Virtual" copy constructor (covariant return type).

void	SetTorsionalStiffness (const double stiffness)
	Set torsional stiffness.

double	GetTorsionalStiffness () const

void	SetTorsionalDamping (const double damping)
	Set torsional damping.

double	GetTorsionalDamping () const

void	SetRestPhase (const double phase)
	Set the phase shaft1-shaft2 for zero torsion of the spring (default = 0).

double	GetRestPhase () const

Public Member Functions inherited from chrono::ChShaftsLoad
	ChShaftsLoad (std::shared_ptr< ChShaft > shaft1, std::shared_ptr< ChShaft > shaft2)

double	GetTorque () const
	Return the actual last computed value of the applied torque, assumed applied to 2ns shaft.

std::shared_ptr< ChShaft >	GetShaft1 () const

std::shared_ptr< ChShaft >	GetShaft2 () const

Public Member Functions inherited from chrono::ChLoadCustomMultiple
	ChLoadCustomMultiple (std::vector< std::shared_ptr< ChLoadable >> &loadable_objects)

	ChLoadCustomMultiple (std::shared_ptr< ChLoadable > loadableA, std::shared_ptr< ChLoadable > loadableB)

	ChLoadCustomMultiple (std::shared_ptr< ChLoadable > loadableA, std::shared_ptr< ChLoadable > loadableB, std::shared_ptr< ChLoadable > loadableC)

virtual int	LoadGetNumCoordsPosLevel () override
	Gets the number of DOFs affected by this load (position part).

virtual int	LoadGetNumCoordsVelLevel () 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 (e.g., as obtained by LoadGetStateBlock_x()) by a given packed state-delta. More...

virtual int	LoadGetNumFieldCoords () override
	Number of coordinates in the interpolated field. More...

virtual void	ComputeJacobian (ChState state_x, ChStateDelta state_w) override
	Compute Jacobian matrices K=-dQ/dx, R=-dQ/dv, and M=-dQ/da. More...

virtual void	LoadIntLoadResidual_F (ChVectorDynamic<> &R, double c) override
	Add the internal loads Q (pasted at global offsets) into a global vector R, multiplied by a scaling factor c. More...

virtual void	LoadIntLoadResidual_Mv (ChVectorDynamic<> &R, const ChVectorDynamic<> &w, double c) override
	Increment a vector R with the matrix-vector product M*w, scaled by the factor c. More...

virtual void	LoadIntLoadLumpedMass_Md (ChVectorDynamic<> &Md, double &err, const double c) override
	Add the lumped mass to an Md vector, representing a mass diagonal matrix. More...

virtual void	CreateJacobianMatrices () override
	Create the Jacobian loads if needed and set the ChVariables referenced by the sparse KRM block.

virtual ChVectorDynamic &	GetQ ()
	Access the generalized load vector Q.

Public Member Functions inherited from chrono::ChLoadBase
ChLoadJacobians *	GetJacobians ()
	Access the Jacobians (if any, i.e. if this is a stiff load).

virtual void	Update (double time)
	Update, called at least at each time step. More...

virtual void	InjectKRMMatrices (ChSystemDescriptor &descriptor)
	Register with the given system descriptor any ChKRMBlock objects associated with this item.

virtual void	LoadKRMMatrices (double Kfactor, double Rfactor, double Mfactor)
	Compute and load current stiffnes (K), damping (R), and mass (M) matrices in encapsulated ChKRMBlock objects. More...

Public Member Functions inherited from chrono::ChObj
	ChObj (const ChObj &other)

int	GetIdentifier () const
	Get the unique integer identifier of this object. More...

void	SetTag (int tag)
	Set an object integer tag (default: -1). More...

int	GetTag () const
	Get the tag of this object.

void	SetName (const std::string &myname)
	Set the name of this object.

const std::string &	GetName () const
	Get the name of this object.

double	GetChTime () const
	Gets the simulation time of this object.

void	SetChTime (double m_time)
	Sets the simulation time of this object.

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.

virtual std::string &	ArchiveContainerName ()

Protected Member Functions
virtual bool	IsStiff () override
	Report if this is load is stiff. More...

virtual void	ComputeShaftShaftTorque (const double rel_rot, const double rel_rot_dt, double &result_torque) override
	Implement the computation of the torque between the two shafts, given relative rotation and velocity. More...

Protected Member Functions inherited from chrono::ChShaftsLoad
virtual void	ComputeQ (ChState state_x, ChStateDelta state_w) override
	Compute Q, the generalized load. More...

Protected Member Functions inherited from chrono::ChObj
int	GenerateUniqueIdentifier ()

Protected Attributes
double	m_stiffness

double	m_damping

double	m_rest_phase

Protected Attributes inherited from chrono::ChShaftsLoad
double	torque
	store computed values here

Protected Attributes inherited from chrono::ChLoadBase
ChLoadJacobians *	m_jacobians

Protected Attributes inherited from chrono::ChObj
double	ChTime
	object simulation time

std::string	m_name
	object name

int	m_identifier
	object unique identifier

int	m_tag
	user-supplied tag

Additional Inherited Members
Public Attributes inherited from chrono::ChLoadCustomMultiple
std::vector< std::shared_ptr< ChLoadable > >	loadables

ChVectorDynamic	load_Q

Constructor & Destructor Documentation

◆ ChShaftsTorsionSpringDamper()

chrono::ChShaftsTorsionSpringDamper::ChShaftsTorsionSpringDamper	(	std::shared_ptr< ChShaft >	shaft1,
		std::shared_ptr< ChShaft >	shaft2,
		const double	stiffness,
		const double	damping
	)

Parameters

shaft1	first shaft
shaft2	second shaft
stiffness	torsional stiffness
damping	torsional damping

Member Function Documentation

◆ ComputeShaftShaftTorque()

void chrono::ChShaftsTorsionSpringDamper::ComputeShaftShaftTorque	(	const double	rel_rot,
		const double	rel_rot_dt,
		double &	result_torque
	)

overrideprotectedvirtual

Implement the computation of the torque between the two shafts, given relative rotation and velocity.

Torque is assumed applied to shaft B, and opposite to A.

Implements chrono::ChShaftsLoad.

◆ IsStiff()

virtual bool chrono::ChShaftsTorsionSpringDamper::IsStiff ( )

inlineoverrideprotectedvirtual

Report if this is load is stiff.

If so, InjectKRMMatrices will provide the Jacobians of the load.

Implements chrono::ChLoadBase.

The documentation for this class was generated from the following files:

/builds/uwsbel/chrono/src/chrono/physics/ChShaftsLoads.h
/builds/uwsbel/chrono/src/chrono/physics/ChShaftsLoads.cpp

Description

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ ChShaftsTorsionSpringDamper()

Member Function Documentation

◆ ComputeShaftShaftTorque()

◆ IsStiff()