chrono::ChLoadBodyBody Class Referenceabstract

Description

Bushing base class.

Base class for wrench loads (a force + a torque) acting between two bodies. See children classes for concrete implementations.

#include <ChLoadsBody.h>

Inheritance diagram for chrono::ChLoadBodyBody:
Collaboration diagram for chrono::ChLoadBodyBody:

Public Member Functions

 ChLoadBodyBody (std::shared_ptr< ChBody > mbodyA, std::shared_ptr< ChBody > mbodyB, const ChFrame<> abs_application)
 
virtual void ComputeBushingForceTorque (const ChFrameMoving<> &rel_AB, ChVector<> &loc_force, ChVector<> &loc_torque)=0
 Compute the force between the two bodies, in local reference loc_application_B, given rel_AB, i.e. More...
 
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 bool IsStiff ()=0
 Return true if stiff load. More...
 
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

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::ChLoadBodyBody::ChLoadBodyBody ( std::shared_ptr< ChBody mbodyA,
std::shared_ptr< ChBody mbodyB,
const ChFrame<>  abs_application 
)
Parameters
mbodyAobject A
mbodyBobject B
abs_applicationcreate the bushing here, in abs. coordinates.

Member Function Documentation

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

Compute the force between the two bodies, in local reference loc_application_B, given rel_AB, i.e.

the position and speed of loc_application_A respect to loc_application_B. Force is assumed applied to body B, and its opposite to A. Inherited classes MUST IMPLEMENT THIS.

Implemented in chrono::ChLoadBodyBodyBushingGeneric, chrono::ChLoadBodyBodyBushingMate, chrono::ChLoadBodyBodyBushingPlastic, and chrono::ChLoadBodyBodyBushingSpherical.

virtual void chrono::ChLoadBodyBody::ComputeQ ( ChState state_x,
ChStateDelta state_w 
)
virtual

Compute Q, the generalized load.

It calls ComputeBushingForceTorque, so in children classes you do not need to implement it. Called automatically at each Update().

Parameters
state_xstate position to evaluate Q
state_wstate speed to evaluate Q

Implements chrono::ChLoadCustomMultiple.