chrono::ChLoadBodyBodyBushingPlastic Class Reference

Description

Load for a visco-elasto-plastic bushing acting between two bodies.

It uses three values for stiffness along the X Y Z axes of a coordinate system attached to the second body. This is equivalent to having a bushing with 3x3 diagonal local stiffness matrix. Also, it allows a very simple plasticity model, to cap the plastic force on x,y,z given three yelds.

#include <ChLoadsBody.h>

Inheritance diagram for chrono::ChLoadBodyBodyBushingPlastic:
Collaboration diagram for chrono::ChLoadBodyBodyBushingPlastic:

Public Member Functions

 ChLoadBodyBodyBushingPlastic (std::shared_ptr< ChBody > mbodyA, std::shared_ptr< ChBody > mbodyB, const ChFrame<> abs_application, const ChVector<> mstiffness, const ChVector<> mdamping, const ChVector<> myeld)
 
virtual void ComputeBushingForceTorque (const ChFrameMoving<> &rel_AB, ChVector<> &loc_force, ChVector<> &loc_torque) override
 Implement the computation of bushing force, in local coordinates of the loc_application_B. More...
 
virtual bool IsStiff ()
 Return true if stiff load. More...
 
void SetYeld (const ChVector<> myeld)
 Set plastic yield, forces beyond this limit will be capped. More...
 
ChVector GetYeld () const
 
ChVector GetPlasticDeformation () const
 Get the current accumulated plastic deformation, in [m], that could become nonzero if forces went beyond the plastic yield. More...
 
- Public Member Functions inherited from chrono::ChLoadBodyBodyBushingSpherical
 ChLoadBodyBodyBushingSpherical (std::shared_ptr< ChBody > mbodyA, std::shared_ptr< ChBody > mbodyB, const ChFrame<> abs_application, const ChVector<> mstiffness, const ChVector<> mdamping)
 
void SetStiffness (const ChVector<> mstiffness)
 Set stiffness, along the x y z axes of loc_application_B, es [N/m].
 
ChVector GetStiffness () const
 
void SetDamping (const ChVector<> mdamping)
 Set damping, along the x y z axes of loc_application_B, es [Ns/m].
 
ChVector GetDamping () const
 
- Public Member Functions inherited from chrono::ChLoadBodyBody
 ChLoadBodyBody (std::shared_ptr< ChBody > mbodyA, std::shared_ptr< ChBody > mbodyB, const ChFrame<> abs_application)
 
ChVector GetBushingForce ()
 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 GetBushingTorque ()
 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
 
virtual void ComputeQ (ChState *state_x, ChStateDelta *state_w)
 Compute Q, the generalized load. More...
 
- 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 ()
 Gets the number of DOFs affected by this load (position part)
 
virtual int LoadGet_ndof_w ()
 Gets the number of DOFs affected by this load (speed part)
 
virtual void LoadGetStateBlock_x (ChState &mD)
 Gets all the current DOFs packed in a single vector (position part)
 
virtual void LoadGetStateBlock_w (ChStateDelta &mD)
 Gets all the current DOFs packed in a single vector (speed part)
 
virtual void LoadStateIncrement (const ChState &x, const ChStateDelta &dw, ChState &x_new)
 Increment a packed state (ex. More...
 
virtual int LoadGet_field_ncoords ()
 Number of coordinates in the interpolated field, ex=3 for a tetrahedron finite element or a cable, = 1 for a thermal problem, etc. More...
 
virtual void ComputeJacobian (ChState *state_x, ChStateDelta *state_w, ChMatrix<> &mK, ChMatrix<> &mR, ChMatrix<> &mM)
 Compute jacobians (default fallback). More...
 
virtual void LoadIntLoadResidual_F (ChVectorDynamic<> &R, const double c)
 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 CreateJacobianMatrices ()
 Create the jacobian loads if needed, and also set the ChVariables referenced by the sparse KRM block. More...
 
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 ()
 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) Basically does nothing, but inherited classes must specialize this. More...
 
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...
 

Protected Attributes

ChVector yield
 
ChVector plastic_def
 
- Protected Attributes inherited from chrono::ChLoadBodyBodyBushingSpherical
ChVector stiffness
 
ChVector damping
 
- Protected Attributes inherited from chrono::ChLoadBodyBody
ChFrame loc_application_A
 
ChFrame loc_application_B
 
ChVector locB_force
 
ChVector locB_torque
 
ChFrameMoving frame_Aw
 
ChFrameMoving frame_Bw
 
- Protected Attributes inherited from chrono::ChLoadBase
ChLoadJacobiansjacobians
 

Additional Inherited Members

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

Constructor & Destructor Documentation

chrono::ChLoadBodyBodyBushingPlastic::ChLoadBodyBodyBushingPlastic ( std::shared_ptr< ChBody mbodyA,
std::shared_ptr< ChBody mbodyB,
const ChFrame<>  abs_application,
const ChVector<>  mstiffness,
const ChVector<>  mdamping,
const ChVector<>  myeld 
)
Parameters
mbodyAobject A
mbodyBobject B
abs_applicationcreate the bushing here, in abs. coordinates. Initial alignment as world xyz.
mstiffnessstiffness, along x y z axes of the abs_application
mdampingdamping, along x y z axes of the abs_application
myeldplastic yield, along x y z axes of the abs_application

Member Function Documentation

virtual void chrono::ChLoadBodyBodyBushingPlastic::ComputeBushingForceTorque ( const ChFrameMoving<> &  rel_AB,
ChVector<> &  loc_force,
ChVector<> &  loc_torque 
)
overridevirtual

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

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

Reimplemented from chrono::ChLoadBodyBodyBushingSpherical.

ChVector chrono::ChLoadBodyBodyBushingPlastic::GetPlasticDeformation ( ) const

Get the current accumulated plastic deformation, in [m], that could become nonzero if forces went beyond the plastic yield.

virtual bool chrono::ChLoadBodyBodyBushingPlastic::IsStiff ( )
virtual

Return true if stiff load.

MUST BE LOAD BY CHILDREN CLASSES!!!

Reimplemented from chrono::ChLoadBodyBodyBushingSpherical.

void chrono::ChLoadBodyBodyBushingPlastic::SetYeld ( const ChVector<>  myeld)

Set plastic yield, forces beyond this limit will be capped.

Expressed along the x y z axes of loc_application_B, es [N/m].