Description

Base class for a vehicle wheel subsystem.

A wheel subsystem does not own a body. Instead, when attached to a suspension subsystem, the wheel's mass properties are used to update those of the spindle body owned by the suspension. A concrete wheel subsystem can optionally carry its own visualization assets (which are associated with the suspension's spindle body).

#include <ChWheel.h>

Inheritance diagram for chrono::vehicle::ChWheel:
Collaboration diagram for chrono::vehicle::ChWheel:

Public Member Functions

virtual std::string GetTemplateName () const override
 Get the name of the vehicle subsystem template.
 
virtual double GetRadius () const
 Get the wheel radius (for visualization only).
 
virtual double GetWidth () const
 Get the wheel width (for visualization only).
 
virtual void Initialize (std::shared_ptr< ChChassis > chassis, std::shared_ptr< ChBody > spindle, VehicleSide side, double offset=0)
 Initialize this wheel subsystem by associating it to an existing spindle of a suspension subsystem. More...
 
void EnableCollision (bool state)
 Enable/disable contact for the wheel. More...
 
void Synchronize ()
 Synchronize the wheel subsystem. More...
 
void Synchronize (const TerrainForce &tire_force)
 Synchronize the wheel subsystem. More...
 
std::shared_ptr< ChTireGetTire () const
 Get the tire attached to this wheel.
 
void SetTire (std::shared_ptr< ChTire > tire)
 Associate the given tire with this wheel.
 
std::shared_ptr< ChBodyGetSpindle () const
 Get the associated spindle body.
 
VehicleSide GetSide () const
 Get the vehicle side on which this wheel is mounted.
 
ChVector3d GetPos () const
 Get wheel position (expressed in absolute frame).
 
WheelState GetState () const
 Get the current state for this wheel. More...
 
virtual void AddVisualizationAssets (VisualizationType vis) override
 Add visualization assets for the wheel subsystem. More...
 
virtual void RemoveVisualizationAssets () override
 Remove visualization assets for the wheel subsystem.
 
const std::string & GetMeshFilename () const
 Get the name of the Wavefront file with wheel visualization mesh. More...
 
- Public Member Functions inherited from chrono::vehicle::ChPart
const std::string & GetName () const
 Get the name identifier for this subsystem.
 
void SetName (const std::string &name)
 Set the name identifier for this subsystem.
 
bool IsInitialized () const
 Return flag indicating whether or not the part is fully constructed.
 
double GetMass () const
 Get the subsystem mass. More...
 
const ChFrameGetCOMFrame () const
 Get the current subsystem COM frame (relative to and expressed in the subsystem's reference frame). More...
 
const ChMatrix33GetInertia () const
 Get the current subsystem inertia (relative to the subsystem COM frame). More...
 
const ChFrameGetTransform () const
 Get the current subsystem position relative to the global frame. More...
 
void SetVisualizationType (VisualizationType vis)
 Set the visualization mode for this subsystem.
 
virtual void SetOutput (bool state)
 Enable/disable output for this subsystem.
 
bool OutputEnabled () const
 Return the output state for this subsystem.
 
virtual void ExportComponentList (rapidjson::Document &jsonDocument) const
 Export this subsystem's component list to the specified JSON object. More...
 
virtual void Output (ChVehicleOutput &database) const
 Output data for this subsystem's component list to the specified database.
 

Protected Member Functions

 ChWheel (const std::string &name)
 Construct a wheel subsystem with given name.
 
virtual void InitializeInertiaProperties () override
 Initialize subsystem inertia properties. More...
 
virtual void UpdateInertiaProperties () override
 Update subsystem inertia properties. More...
 
virtual double GetWheelMass () const =0
 
virtual const ChVector3dGetWheelInertia () const =0
 
- Protected Member Functions inherited from chrono::vehicle::ChPart
 ChPart (const std::string &name)
 Construct a vehicle subsystem with the specified name.
 
void AddMass (double &mass)
 Add this subsystem's mass. More...
 
void AddInertiaProperties (ChVector3d &com, ChMatrix33<> &inertia)
 Add this subsystem's inertia properties. More...
 
virtual void Create (const rapidjson::Document &d)
 Create a vehicle subsystem from JSON data. More...
 
void ExportBodyList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChBody >> bodies) const
 Export the list of bodies to the specified JSON document.
 
void ExportShaftList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChShaft >> shafts) const
 Export the list of shafts to the specified JSON document.
 
void ExportJointList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLink >> joints) const
 Export the list of joints to the specified JSON document.
 
void ExportCouplesList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChShaftsCouple >> couples) const
 Export the list of shaft couples to the specified JSON document.
 
void ExportMarkerList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChMarker >> markers) const
 Export the list of markers to the specified JSON document.
 
void ExportLinSpringList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLinkTSDA >> springs) const
 Export the list of translational springs to the specified JSON document.
 
void ExportRotSpringList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLinkRSDA >> springs) const
 Export the list of rotational springs to the specified JSON document.
 
void ExportBodyLoadList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLoadBodyBody >> loads) const
 Export the list of body-body loads to the specified JSON document.
 

Protected Attributes

std::shared_ptr< ChBodym_spindle
 associated suspension spindle body
 
std::shared_ptr< ChTirem_tire
 attached tire subsystem
 
VehicleSide m_side
 wheel mounted on left/right side
 
double m_offset
 offset from spindle center
 
std::string m_vis_mesh_file
 visualization mesh file (may be empty)
 
std::shared_ptr< ChVisualShapeTriangleMeshm_trimesh_shape
 visualization mesh asset
 
std::shared_ptr< ChVisualShapem_cyl_shape
 visualization cylinder asset
 
std::shared_ptr< ChLoadBodyForcem_spindle_terrain_force
 terrain force loads on the spindle
 
std::shared_ptr< ChLoadBodyTorquem_spindle_terrain_torque
 terrain torque loads on the spindle
 
- Protected Attributes inherited from chrono::vehicle::ChPart
std::string m_name
 subsystem name
 
bool m_initialized
 specifies whether ot not the part is fully constructed
 
bool m_output
 specifies whether or not output is generated for this subsystem
 
std::shared_ptr< ChPartm_parent
 parent subsystem (empty if parent is vehicle)
 
double m_mass
 subsystem mass
 
ChMatrix33 m_inertia
 inertia tensor (relative to subsystem COM)
 
ChFrame m_com
 COM frame (relative to subsystem reference frame)
 
ChFrame m_xform
 subsystem frame expressed in the global frame
 

Friends

class ChTire
 
class ChWheeledVehicle
 
class ChTireTestRig
 

Additional Inherited Members

- Static Public Member Functions inherited from chrono::vehicle::ChPart
static ChMatrix33 TransformInertiaMatrix (const ChVector3d &moments, const ChVector3d &products, const ChMatrix33<> &vehicle_rot, const ChMatrix33<> &body_rot)
 Utility function for transforming inertia tensors between centroidal frames. More...
 
- Static Protected Member Functions inherited from chrono::vehicle::ChPart
static void RemoveVisualizationAssets (std::shared_ptr< ChPhysicsItem > item)
 Erase all visual shapes from the visual model associated with the specified physics item (if any).
 
static void RemoveVisualizationAsset (std::shared_ptr< ChPhysicsItem > item, std::shared_ptr< ChVisualShape > shape)
 Erase the given shape from the visual model associated with the specified physics item (if any).
 

Member Function Documentation

◆ AddVisualizationAssets()

void chrono::vehicle::ChWheel::AddVisualizationAssets ( VisualizationType  vis)
overridevirtual

Add visualization assets for the wheel subsystem.

This default implementation uses primitives.

Reimplemented from chrono::vehicle::ChPart.

Reimplemented in chrono::vehicle::artcar::ARTcar_Wheel.

◆ EnableCollision()

void chrono::vehicle::ChWheel::EnableCollision ( bool  state)
inline

Enable/disable contact for the wheel.

This function controls contact of the wheel with all other collision shapes in the simulation. Must be called after initialization and has effect only if the derived object has defined some collision shapes.

◆ GetMeshFilename()

const std::string& chrono::vehicle::ChWheel::GetMeshFilename ( ) const
inline

Get the name of the Wavefront file with wheel visualization mesh.

An empty string is returned if no mesh was specified.

◆ GetState()

WheelState chrono::vehicle::ChWheel::GetState ( ) const

Get the current state for this wheel.

This includes the location, orientation, linear and angular velocities, all expressed in the global reference frame, as well as the wheel angular speed about its rotation axis.

◆ Initialize()

void chrono::vehicle::ChWheel::Initialize ( std::shared_ptr< ChChassis chassis,
std::shared_ptr< ChBody spindle,
VehicleSide  side,
double  offset = 0 
)
virtual

Initialize this wheel subsystem by associating it to an existing spindle of a suspension subsystem.

The optional 'offset' argument allows models with double wheels(tires). The default value offset=0 corresponds to an axle with a single tire. A positive offset corresponds to an "outer" wheel, while a negative offset corresponds to an "inner" wheel. The wheel mass and inertia are used to increment those of the associated spindle body.

Parameters
chassischassis vehicle (may be null)
spindleassociated suspension spindle body
sidewheel mounted on left/right side
offsetoffset from associated spindle center

Reimplemented in chrono::vehicle::jeep::Cherokee_Wheel, chrono::vehicle::hmmwv::HMMWV_Wheel, and chrono::vehicle::generic::Generic_Wheel.

◆ InitializeInertiaProperties()

void chrono::vehicle::ChWheel::InitializeInertiaProperties ( )
overrideprotectedvirtual

Initialize subsystem inertia properties.

Derived classes must override this function and set the subsystem mass (m_mass) and, if constant, the subsystem COM frame and its inertia tensor. This function is called during initialization of the vehicle system.

Implements chrono::vehicle::ChPart.

◆ Synchronize() [1/2]

void chrono::vehicle::ChWheel::Synchronize ( )

Synchronize the wheel subsystem.

This version queries the forces from the attached tire and applies them to the associated suspension.

◆ Synchronize() [2/2]

void chrono::vehicle::ChWheel::Synchronize ( const TerrainForce tire_force)

Synchronize the wheel subsystem.

This version uses the provided forces as external applied tire/terrain forces.

◆ UpdateInertiaProperties()

void chrono::vehicle::ChWheel::UpdateInertiaProperties ( )
overrideprotectedvirtual

Update subsystem inertia properties.

Derived classes must override this function and set the global subsystem transform (m_xform) and, unless constant, the subsystem COM frame (m_com) and its inertia tensor (m_inertia). Calculate the current inertia properties and global frame of this subsystem. This function is called every time the state of the vehicle system is advanced in time.

Implements chrono::vehicle::ChPart.


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono_vehicle/wheeled_vehicle/ChWheel.h
  • /builds/uwsbel/chrono/src/chrono_vehicle/wheeled_vehicle/ChWheel.cpp