chrono::ChLoadBodyBodyBushingGeneric Class Reference

Description

Load for a visco-elastic translational/rotational bushing acting between two bodies.

It uses a full user-defined 6x6 matrix [K] to express the local stiffness of the bushing, assumed expressed in the bushing coordinate system attached to the second body. A user-defined 6x6 matrix [D] can be defined for damping, as well. Note that this assumes small rotations. Differently from the simpler ChLoadBodyBodyBushingMate and ChLoadBodyBodyBushingSpherical this can represent coupled effects, by using extra-diagonal terms in [K] and/or [D].

#include <ChLoadsBody.h>

Inheritance diagram for chrono::ChLoadBodyBodyBushingGeneric:
Collaboration diagram for chrono::ChLoadBodyBodyBushingGeneric:

Public Member Functions

 ChLoadBodyBodyBushingGeneric (std::shared_ptr< ChBody > mbodyA, std::shared_ptr< ChBody > mbodyB, const ChFrame<> &abs_application, ChMatrixConstRef mstiffness, ChMatrixConstRef mdamping)
 
virtual ChLoadBodyBodyBushingGenericClone () const override
 "Virtual" copy constructor (covariant return type).
 
void SetStiffnessMatrix (ChMatrixConstRef mstiffness)
 Set a generic 6x6 stiffness matrix, expressed in local coordinate system of loc_application_B.
 
const ChMatrixNM< double, 6, 6 > & GetStiffnessMatrix () const
 
void SetDampingMatrix (ChMatrixConstRef mdamping)
 Set a generic 6x6 damping matrix, expressed in local coordinate system of loc_application_B.
 
const ChMatrixNM< double, 6, 6 > & GetDampingMatrix () const
 
void SetNeutralForce (const ChVector<> mf)
 Set the initial pre-load of the bushing, applied to loc_application_A, expressed in local coordinate system of loc_application_B. More...
 
ChVector GetNeutralForce () const
 
void SetNeutralTorque (const ChVector<> mt)
 Set the initial pre-load torque of the bushing, applied to loc_application_A, expressed in local coordinate system of loc_application_B. More...
 
ChVector GetNeutralTorque () const
 
ChFrameNeutralDisplacement ()
 Set/get the initial pre-displacement of the bushing, as the pre-displacement of A, expressed in local coordinate system of loc_application_B. More...
 
- Public Member Functions inherited from chrono::ChLoadBodyBody
 ChLoadBodyBody (std::shared_ptr< ChBody > bodyA, std::shared_ptr< ChBody > bodyB, const ChFrame<> &abs_application)
 
ChVector GetForce () const
 For diagnosis purposes, this can return the actual last computed value of the applied force, expressed in coordinate system of loc_application_B, assumed applied to body B.
 
ChVector GetTorque () const
 For diagnosis purposes, this can return the actual last computed value of the applied torque, expressed in coordinate system of loc_application_B, assumed applied to body B.
 
void SetApplicationFrameA (const ChFrame<> &mpA)
 Set the application frame of bushing on bodyA.
 
ChFrame GetApplicationFrameA () const
 
void SetApplicationFrameB (const ChFrame<> &mpB)
 Set the application frame of bushing on bodyB.
 
ChFrame GetApplicationFrameB () const
 
ChFrameMoving GetAbsoluteFrameA () const
 Get absolute coordinate of frame A (last computed)
 
ChFrameMoving GetAbsoluteFrameB () const
 Get absolute coordinate of frame B (last computed)
 
std::shared_ptr< ChBodyGetBodyA () const
 
std::shared_ptr< ChBodyGetBodyB () const
 
- Public Member Functions inherited from chrono::ChLoadCustomMultiple
 ChLoadCustomMultiple (std::vector< std::shared_ptr< ChLoadable >> &mloadables)
 
 ChLoadCustomMultiple (std::shared_ptr< ChLoadable > mloadableA, std::shared_ptr< ChLoadable > mloadableB)
 
 ChLoadCustomMultiple (std::shared_ptr< ChLoadable > mloadableA, std::shared_ptr< ChLoadable > mloadableB, std::shared_ptr< ChLoadable > mloadableC)
 
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 Update (double time)
 Update: this is called at least at each time step. More...
 
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
 Report if this is load is stiff. More...
 
virtual void ComputeBodyBodyForceTorque (const ChFrameMoving<> &rel_AB, ChVector<> &loc_force, ChVector<> &loc_torque) override
 Implement the computation of the bushing force, in local coordinates of the loc_application_B. More...
 
- Protected Member Functions inherited from chrono::ChLoadBodyBody
virtual void ComputeQ (ChState *state_x, ChStateDelta *state_w) override
 Compute Q, the generalized load. More...
 

Protected Attributes

ChMatrixNM< double, 6, 6 > stiffness
 
ChMatrixNM< double, 6, 6 > damping
 
ChVector neutral_force
 
ChVector neutral_torque
 
ChFrame neutral_displacement
 
- Protected Attributes inherited from chrono::ChLoadBodyBody
ChFrame loc_application_A
 application point on body A (local)
 
ChFrame loc_application_B
 application point on body B (local)
 
ChVector locB_force
 store computed values here
 
ChVector locB_torque
 store computed values here
 
ChFrameMoving frame_Aw
 for results
 
ChFrameMoving frame_Bw
 for results
 
- Protected Attributes inherited from chrono::ChLoadBase
ChLoadJacobiansjacobians
 
- Protected Attributes inherited from chrono::ChObj
double ChTime
 the time of simulation for the object
 

Additional Inherited Members

- Public Attributes inherited from chrono::ChLoadCustomMultiple
std::vector< std::shared_ptr< ChLoadable > > loadables
 
ChVectorDynamic load_Q
 

Constructor & Destructor Documentation

◆ ChLoadBodyBodyBushingGeneric()

chrono::ChLoadBodyBodyBushingGeneric::ChLoadBodyBodyBushingGeneric ( std::shared_ptr< ChBody mbodyA,
std::shared_ptr< ChBody mbodyB,
const ChFrame<> &  abs_application,
ChMatrixConstRef  mstiffness,
ChMatrixConstRef  mdamping 
)
Parameters
mbodyAbody A
mbodyBbody B
abs_applicationcreate the bushing here, in abs. coordinates.
mstiffnessstiffness as a 6x6 matrix, local in the abs_application frame
mdampingdamping as a 6x6 matrix, local in the abs_application frame

Member Function Documentation

◆ ComputeBodyBodyForceTorque()

void chrono::ChLoadBodyBodyBushingGeneric::ComputeBodyBodyForceTorque ( const ChFrameMoving<> &  rel_AB,
ChVector<> &  loc_force,
ChVector<> &  loc_torque 
)
overrideprotectedvirtual

Implement the computation of the bushing force, in local coordinates of the loc_application_B.

Force is assumed applied to loc_application_B of body B, and its opposite reaction to A.

Implements chrono::ChLoadBodyBody.

◆ IsStiff()

virtual bool chrono::ChLoadBodyBodyBushingGeneric::IsStiff ( )
inlineoverrideprotectedvirtual

Report if this is load is stiff.

If so, InjectKRMmatrices will provide the jacobians of the load.

Implements chrono::ChLoadBase.

◆ NeutralDisplacement()

ChFrame& chrono::ChLoadBodyBodyBushingGeneric::NeutralDisplacement ( )
inline

Set/get the initial pre-displacement of the bushing, as the pre-displacement of A, expressed in local coordinate system of loc_application_B.

Default behavior is no initial pre-displacement.

◆ SetNeutralForce()

void chrono::ChLoadBodyBodyBushingGeneric::SetNeutralForce ( const ChVector<>  mf)
inline

Set the initial pre-load of the bushing, applied to loc_application_A, expressed in local coordinate system of loc_application_B.

By default it is zero.

◆ SetNeutralTorque()

void chrono::ChLoadBodyBodyBushingGeneric::SetNeutralTorque ( const ChVector<>  mt)
inline

Set the initial pre-load torque of the bushing, applied to loc_application_A, expressed in local coordinate system of loc_application_B.

By default it is zero.


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