chrono::ChShaftsGearboxAngled Class Reference

## Description

Class for defining a gearbox with 1D input and 1D output, but with different directions in 3D space.

Basically it defines a transmission ratio between two 1D entities of ChShaft type, and transmits the reaction of the gearbox to a 3D body that acts as the support truss. A typical example is the case of a gearbox with bevel gears, where input shaft and output shaft are at 90°. Note that the more basic ChShaftsGear can do the same, except that it does not provide a way to transmit reaction to a truss body.

#include <ChShaftsGearboxAngled.h>

Inheritance diagram for chrono::ChShaftsGearboxAngled:
Collaboration diagram for chrono::ChShaftsGearboxAngled:

## Public Member Functions

ChShaftsGearboxAngled (const ChShaftsGearboxAngled &other)

virtual ChShaftsGearboxAngledClone () const override
"Virtual" copy constructor (covariant return type).

virtual int GetNumCoords () const
Get the number of scalar variables affected by constraints in this link.

virtual int GetDOC_c () override
Number of scalar constraints.

virtual void IntStateGatherReactions (const unsigned int off_L, ChVectorDynamic<> &L) override
From item's reaction forces to global reaction vector.

virtual void IntStateScatterReactions (const unsigned int off_L, const ChVectorDynamic<> &L) override
From global reaction vector to item's reaction forces.

virtual void IntLoadResidual_CqL (const unsigned int off_L, ChVectorDynamic<> &R, const ChVectorDynamic<> &L, const double c) override
Takes the term Cq'*L, scale and adds to R at given offset: R += c*Cq'*L.

virtual void IntLoadConstraint_C (const unsigned int off, ChVectorDynamic<> &Qc, const double c, bool do_clamp, double recovery_clamp) override
Takes the term C, scale and adds to Qc at given offset: Qc += c*C.

virtual void IntToDescriptor (const unsigned int off_v, const ChStateDelta &v, const ChVectorDynamic<> &R, const unsigned int off_L, const ChVectorDynamic<> &L, const ChVectorDynamic<> &Qc) override
Prepare variables and constraints to accommodate a solution:

virtual void IntFromDescriptor (const unsigned int off_v, ChStateDelta &v, const unsigned int off_L, ChVectorDynamic<> &L) override
After a solver solution, fetch values from variables and constraints into vectors:

virtual void InjectConstraints (ChSystemDescriptor &mdescriptor) override
Tell to a system descriptor that there are constraints of type ChConstraint in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this. More...

virtual void ConstraintsBiReset () override
Sets to zero the known term (b_i) of encapsulated ChConstraints.

virtual void ConstraintsBiLoad_C (double factor=1, double recovery_clamp=0.1, bool do_clamp=false) override
Adds the current C (constraint violation) to the known term (b_i) of encapsulated ChConstraints.

virtual void ConstraintsBiLoad_Ct (double factor=1) override
Adds the current Ct (partial t-derivative, as in C_dt=0-> [Cq]*q_dt=-Ct) to the known term (b_i) of encapsulated ChConstraints.

Adds the current jacobians in encapsulated ChConstraints.

virtual void ConstraintsFetch_react (double factor=1) override
Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...

virtual bool Initialize (std::shared_ptr< ChShaft > mshaft1, std::shared_ptr< ChShaft > mshaft2, std::shared_ptr< ChBodyFrame > mbody, ChVector<> &mdir1, ChVector<> &mdir2)
Use this function after gear creation, to initialize it, given two shafts to join, and the 3D body that acts as a truss and receives the reaction torque of the gearbox. More...

ChShaftGetShaft1 ()
Get the first shaft (carrier wheel)

ChShaftGetShaft2 ()
Get the second shaft.

ChBodyFrameGetBodyTruss ()
Get the third shaft.

void SetTransmissionRatio (double mt0)
Set the transmission ratio t, as in w2=t*w1, or t=w2/w1 , or t*w1 - w2 = 0. More...

double GetTransmissionRatio () const
Get the transmission ratio t, as in w2=t*w1, or t=w2/w1.

void SetShaftDirection1 (ChVector<> md)
Set the direction of shaft 1 (input) respect to 3D body, as a normalized vector expressed in the coordinates of the body. More...

void SetShaftDirection2 (ChVector<> md)
Set the direction of shaft 2 (output) respect to 3D body, as a normalized vector expressed in the coordinates of the body. More...

const ChVectorGetShaftDirection1 () const
Get the direction of the shaft 1 (input) respect to 3D body, as a normalized vector expressed in the coordinates of the body. More...

const ChVectorGetShaftDirection2 () const
Get the direction of the shaft 2 (input) respect to 3D body, as a normalized vector expressed in the coordinates of the body. More...

double GetTorqueReactionOn1 () const
Get the reaction torque considered as applied to the 1st axis.

double GetTorqueReactionOn2 () const
Get the reaction torque considered as applied to the 2nd axis.

ChVector GetTorqueReactionOnBody () const
Get the reaction torque considered as applied to the body (the truss of the gearbox), expressed in local body coordinates. More...

virtual void Update (double mytime, bool update_assets=true) override
Update all auxiliary data of the gear transmission at given time.

virtual void ArchiveOUT (ChArchiveOut &marchive) override
Method to allow serialization of transient data to archives.

virtual void ArchiveIN (ChArchiveIn &marchive) override
Method to allow deserialization of transient data from archives. More...

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

ChSystemGetSystem () const
Get the pointer to the parent ChSystem()

virtual void SetSystem (ChSystem *m_system)
Set the pointer to the parent ChSystem() and also add to new collision system / remove from old coll.system.

void AddAsset (std::shared_ptr< ChAsset > masset)
Add an optional asset (it can be used to define visualization shapes, es ChSphereShape, or textures, or custom attached properties that the user can define by creating his class inherited from ChAsset)

std::vector< std::shared_ptr< ChAsset > > & GetAssets ()

std::shared_ptr< ChAssetGetAssetN (unsigned int num)
Access the Nth asset in the list of optional assets.

virtual ChFrame GetAssetsFrame (unsigned int nclone=0)
Get the master coordinate system for assets that have some geometric meaning. More...

virtual unsigned int GetAssetsFrameNclones ()
Optionally, a ChPhysicsItem can return multiple asset coordinate systems; this can be helpful if, for example, when a ChPhysicsItem contains 'clones' with the same assets (ex. More...

virtual bool GetCollide () const
Tell if the object is subject to collision. More...

virtual void SyncCollisionModels ()
If this physical item contains one or more collision models, synchronize their coordinates and bounding boxes to the state of the item. More...

If this physical item contains one or more collision models, add them to the system's collision engine. More...

virtual void RemoveCollisionModelsFromSystem ()
If this physical item contains one or more collision models, remove them from the system's collision engine. More...

virtual void GetTotalAABB (ChVector<> &bbmin, ChVector<> &bbmax)
Get the entire AABB axis-aligned bounding box of the object. More...

virtual void GetCenter (ChVector<> &mcenter)
Get a symbolic 'center' of the object. More...

virtual void StreamINstate (ChStreamInBinary &mstream)
Method to deserialize only the state (position, speed) Must be implemented by child classes. More...

virtual void StreamOUTstate (ChStreamOutBinary &mstream)
Method to serialize only the state (position, speed) Must be implemented by child classes. More...

virtual void Setup ()
This might recompute the number of coordinates, DOFs, constraints, in case this might change (ex in ChAssembly), as well as state offsets of contained items (ex in ChMesh)

virtual void Update (bool update_assets=true)
As above, but does not require updating of time-dependent data. More...

virtual void SetNoSpeedNoAcceleration ()
Set zero speed (and zero accelerations) in state, without changing the position. More...

virtual int GetDOF ()
Get the number of scalar coordinates (variables), if any, in this item. More...

virtual int GetDOF_w ()
Get the number of scalar coordinates of variables derivatives (usually = DOF, but might be different than DOF, ex. More...

virtual int GetDOC ()
Get the number of scalar constraints, if any, in this item.

virtual int GetDOC_d ()
Get the number of scalar constraints, if any, in this item (only unilateral constr.) Children classes might override this. More...

unsigned int GetOffset_x ()
Get offset in the state vector (position part)

unsigned int GetOffset_w ()
Get offset in the state vector (speed part)

unsigned int GetOffset_L ()
Get offset in the lagrangian multipliers.

void SetOffset_x (const unsigned int moff)
Set offset in the state vector (position part) Note: only the ChSystem::Setup function should use this.

void SetOffset_w (const unsigned int moff)
Set offset in the state vector (speed part) Note: only the ChSystem::Setup function should use this.

void SetOffset_L (const unsigned int moff)
Set offset in the lagrangian multipliers Note: only the ChSystem::Setup function should use this.

virtual void IntStateGather (const unsigned int off_x, ChState &x, const unsigned int off_v, ChStateDelta &v, double &T)
From item's state to global state vectors y={x,v} pasting the states at the specified offsets. More...

virtual void IntStateScatter (const unsigned int off_x, const ChState &x, const unsigned int off_v, const ChStateDelta &v, const double T)
From global state vectors y={x,v} to item's state (and update) fetching the states at the specified offsets. More...

virtual void IntStateGatherAcceleration (const unsigned int off_a, ChStateDelta &a)
From item's state acceleration to global acceleration vector. More...

virtual void IntStateScatterAcceleration (const unsigned int off_a, const ChStateDelta &a)
From global acceleration vector to item's state acceleration. More...

virtual void IntStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv)
Computes x_new = x + Dt , using vectors at specified offsets. More...

virtual void IntLoadResidual_F (const unsigned int off, ChVectorDynamic<> &R, const double c)
Takes the F force term, scale and adds to R at given offset: R += c*F. More...

virtual void IntLoadResidual_Mv (const unsigned int off, ChVectorDynamic<> &R, const ChVectorDynamic<> &w, const double c)
Takes the M*v term, multiplying mass by a vector, scale and adds to R at given offset: R += c*M*w. More...

virtual void IntLoadConstraint_Ct (const unsigned int off, ChVectorDynamic<> &Qc, const double c)
Takes the term Ct, scale and adds to Qc at given offset: Qc += c*Ct. More...

virtual void VariablesFbReset ()
Sets the 'fb' part (the known term) of the encapsulated ChVariables to zero.

Adds the current forces (applied to item) into the encapsulated ChVariables, in the 'fb' part: qf+=forces*factor.

Initialize the 'qb' part of the ChVariables with the current value of speeds. More...

virtual void VariablesFbIncrementMq ()
Adds M*q (masses multiplied current 'qb') to Fb, ex. More...

virtual void VariablesQbSetSpeed (double step=0)
Fetches the item speed (ex. More...

virtual void VariablesQbIncrementPosition (double step)
Increment item positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor. More...

virtual void InjectVariables (ChSystemDescriptor &mdescriptor)
Tell to a system descriptor that there are variables of type ChVariables in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this. More...

Adds the current Qc (the vector of C_dtdt=0 -> [Cq]*q_dtdt=Qc ) to the known term (b_i) of encapsulated ChConstraints.

Adds the current link-forces, if any, (caused by springs, etc.) to the 'fb' vectors of the ChVariables referenced by encapsulated ChConstraints.

virtual void InjectKRMmatrices (ChSystemDescriptor &mdescriptor)
Tell to a system descriptor that there are items of type ChKblock in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may 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...

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)

Protected Attributes inherited from chrono::ChPhysicsItem
ChSystemsystem
parent system

std::vector< std::shared_ptr< ChAsset > > assets
set of assets

unsigned int offset_x
offset in vector of state (position part)

unsigned int offset_w
offset in vector of state (speed part)

unsigned int offset_L
offset in vector of lagrangian multipliers

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

## Member Function Documentation

 void chrono::ChShaftsGearboxAngled::ArchiveIN ( ChArchiveIn & marchive )
overridevirtual

Method to allow deserialization of transient data from archives.

Method to allow de serialization of transient data from archives.

Reimplemented from chrono::ChPhysicsItem.

 void chrono::ChShaftsGearboxAngled::ConstraintsFetch_react ( double factor = 1 )
overridevirtual

Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints.

Mostly used after the solver provided the solution in ChConstraints. Also, should convert the reactions obtained from dynamical simulation, from link space to intuitive react_force and react_torque.

Reimplemented from chrono::ChPhysicsItem.

 const ChVector& chrono::ChShaftsGearboxAngled::GetShaftDirection1 ( ) const

Get the direction of the shaft 1 (input) respect to 3D body, as a normalized vector expressed in the coordinates of the body.

 const ChVector& chrono::ChShaftsGearboxAngled::GetShaftDirection2 ( ) const

Get the direction of the shaft 2 (input) respect to 3D body, as a normalized vector expressed in the coordinates of the body.

 ChVector chrono::ChShaftsGearboxAngled::GetTorqueReactionOnBody ( ) const

Get the reaction torque considered as applied to the body (the truss of the gearbox), expressed in local body coordinates.

 bool chrono::ChShaftsGearboxAngled::Initialize ( std::shared_ptr< ChShaft > mshaft1, std::shared_ptr< ChShaft > mshaft2, std::shared_ptr< ChBodyFrame > mbody, ChVector<> & mdir1, ChVector<> & mdir2 )
virtual

Use this function after gear creation, to initialize it, given two shafts to join, and the 3D body that acts as a truss and receives the reaction torque of the gearbox.

Each shaft and body must belong to the same ChSystem. Shafts directions are considered in local body coordinates.

Parameters
 mshaft1 first (input) shaft to join mshaft2 second (output) shaft to join mbody 3D body to use as truss (also carrier, if rotates as in planetary gearboxes) mdir1 the direction of the first shaft on 3D body defining the gearbox truss mdir2 the direction of the first shaft on 3D body defining the gearbox truss
 void chrono::ChShaftsGearboxAngled::InjectConstraints ( ChSystemDescriptor & mdescriptor )
overridevirtual

Tell to a system descriptor that there are constraints of type ChConstraint in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this.

Reimplemented from chrono::ChPhysicsItem.

 void chrono::ChShaftsGearboxAngled::SetShaftDirection1 ( ChVector<> md )

Set the direction of shaft 1 (input) respect to 3D body, as a normalized vector expressed in the coordinates of the body.