Description

Concrete tire class that implements the Pacejka tire model.

#include <ChPacejkaTire.h>

Inheritance diagram for chrono::vehicle::ChPacejkaTire:
Collaboration diagram for chrono::vehicle::ChPacejkaTire:

Public Member Functions

 ChPacejkaTire (const std::string &name, const std::string &pacTire_paramFile)
 Default constructor for a Pacejka tire. More...
 
 ChPacejkaTire (const std::string &name, const std::string &pacTire_paramFile, double Fz_override, bool use_transient_slip=true)
 Construct a Pacejka tire with specified vertical load, for testing purposes. More...
 
virtual std::string GetTemplateName () const override
 Get the name of the vehicle subsystem template.
 
void SetDrivenWheel (bool val)
 Specify whether or not the associated wheel is driven. More...
 
virtual void AddVisualizationAssets (VisualizationType vis) override
 Add visualization assets for the rigid tire subsystem.
 
virtual void RemoveVisualizationAssets () override
 Remove visualization assets for the rigid tire subsystem.
 
virtual double GetRadius () const override
 Get the tire radius.
 
virtual double GetWidth () const override
 Get tire width.
 
virtual double GetVisualizationWidth () const
 Get visualization tire width.
 
TerrainForce GetTireForce_pureSlip (const bool local=true) const
 Return the reactions for the pure slip EQs, in local or global coords.
 
TerrainForce GetTireForce_combinedSlip (const bool local=true) const
 Return the reactions for the combined slip EQs, in local or global coords. More...
 
double GetSlipAngle_internal () const
 Get the tire slip angle computed internally by the Pacejka model (in radians). More...
 
double GetLongitudinalSlip_internal () const
 Get the tire longitudinal slip computed internally by the Pacejka model. More...
 
double GetCamberAngle_internal () const
 Get the camber angle for the Pacejka tire model (in radians). More...
 
void WriteOutData (double time, const std::string &outFilename)
 Write output data to a file.
 
void set_Fz_override (double Fz)
 Manually set the vertical wheel load as an input.
 
WheelState getState_from_KAG (double kappa, double alpha, double gamma, double Vx)
 Return orientation, Vx (global) and omega/omega_y (global). More...
 
double get_average_Advance_time ()
 Get the average simulation time per step spent in advance()
 
double get_average_ODE_time ()
 Get the average simulation time per step spent in calculating ODEs.
 
double get_kappa () const
 Get current wheel longitudinal slip.
 
double get_alpha () const
 Get current wheel slip angle.
 
double get_gamma () const
 Get current wheel camber angle.
 
double get_kappaPrime () const
 Get current long slip rate used in Magic Formula EQs.
 
double get_alphaPrime () const
 Get current slip angle using in Magic Formula.
 
double get_gammaPrime () const
 Get current camber angle used in Magic Formula.
 
double get_min_long_slip () const
 Get minimum longitudinal slip rate.
 
double get_max_long_slip () const
 Get maximum longitudinal slip rate.
 
double get_min_lat_slip () const
 Get the minimum allowable lateral slip angle, alpha.
 
double get_max_lat_slip () const
 Get the maximum allowable lateral slip angle, alpha.
 
double get_longvl () const
 Get the longitudinal velocity.
 
double get_tire_rolling_rad () const
 Get the tire rolling radius, ideally updated each step.
 
- Public Member Functions inherited from chrono::vehicle::ChForceElementTire
virtual TerrainForce ReportTireForce (ChTerrain *terrain) const override
 Report the tire force and moment.
 
virtual TerrainForce ReportTireForce (ChTerrain *terrain, ChCoordsys<> &tire_frame) const override
 Get the tire forces expressed in the tire frame. More...
 
- Public Member Functions inherited from chrono::vehicle::ChTire
void SetStepsize (double val)
 Set the value of the integration step size for the underlying dynamics (if applicable). More...
 
double GetStepsize () const
 Get the current value of the integration step size.
 
void SetCollisionType (CollisionType collision_type)
 Set the collision type for tire-terrain interaction. More...
 
virtual double GetTireMass () const =0
 Return the tire mass.
 
virtual ChVector GetTireInertia () const =0
 Return the tire moments of inertia (in the tire centroidal frame).
 
double GetSlipAngle () const
 Return the tire slip angle calculated based on the current state of the associated wheel body. More...
 
double GetLongitudinalSlip () const
 Return the tire longitudinal slip calculated based on the current state of the associated wheel body. More...
 
double GetCamberAngle () const
 Return the tire camber angle calculated based on the current state of the associated wheel body. More...
 
virtual double GetDeflection () const
 Report the tire deflection.
 
const std::string & GetMeshFilename () const
 Get the name of the Wavefront file with tire 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

const std::string & getPacTireParamFile () const
 
- Protected Member Functions inherited from chrono::vehicle::ChForceElementTire
 ChForceElementTire (const std::string &name)
 Construct a tire with the specified name.
 
- Protected Member Functions inherited from chrono::vehicle::ChTire
 ChTire (const std::string &name)
 Construct a tire subsystem with given name.
 
void CalculateKinematics (const WheelState &wheel_state, const ChCoordsys<> &tire_frame)
 Calculate kinematics quantities based on the given state of the associated wheel body. More...
 
double GetOffset () const
 Get offset from spindle center. More...
 
std::shared_ptr< ChTriangleMeshShapeAddVisualizationMesh (const std::string &mesh_file_left, const std::string &mesh_file_right)
 Add mesh visualization to the body associated with this tire (a wheel spindle body). More...
 
- 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 (ChVector<> &com, ChMatrix33<> &inertia)
 Add this subsystem's inertia properties. 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::string m_paramFile
 
- Protected Attributes inherited from chrono::vehicle::ChForceElementTire
ContactData m_data
 tire-terrain collision information
 
TerrainForce m_tireforce
 tire forces (in tire contact frame)
 
ChFunction_Recorder m_areaDep
 
- Protected Attributes inherited from chrono::vehicle::ChTire
std::shared_ptr< ChWheelm_wheel
 associated wheel subsystem
 
double m_stepsize
 tire integration step size (if applicable)
 
CollisionType m_collision_type
 method used for tire-terrain collision
 
std::string m_vis_mesh_file
 name of OBJ file for visualization of this tire (may be empty)
 
double m_slip_angle
 
double m_longitudinal_slip
 
double m_camber_angle
 
- 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
 

Additional Inherited Members

- Public Types inherited from chrono::vehicle::ChTire
enum  CollisionType { SINGLE_POINT, FOUR_POINTS, ENVELOPE }
 
- Static Public Member Functions inherited from chrono::vehicle::ChTire
static ChVector EstimateInertia (double tire_width, double aspect_ratio, double rim_diameter, double tire_mass, double t_factor=2)
 Utility function for estimating the tire moments of inertia. More...
 
- Static Public Member Functions inherited from chrono::vehicle::ChPart
static ChMatrix33 TransformInertiaMatrix (const ChVector<> &moments, const ChVector<> &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::ChTire
static bool DiscTerrainCollision (CollisionType method, const ChTerrain &terrain, const ChVector<> &disc_center, const ChVector<> &disc_normal, double disc_radius, double width, const ChFunction_Recorder &areaDep, ChCoordsys<> &contact, double &depth, float &mu)
 Perform disc-terrain collision detection, using the specified method. More...
 
static void ConstructAreaDepthTable (double disc_radius, ChFunction_Recorder &areaDep)
 Utility function to construct a loopkup table for penetration depth as function of intersection area, for a given tire radius. More...
 
static bool DiscTerrainCollision1pt (const ChTerrain &terrain, const ChVector<> &disc_center, const ChVector<> &disc_normal, double disc_radius, ChCoordsys<> &contact, double &depth, float &mu)
 Perform disc-terrain collision detection. More...
 
static bool DiscTerrainCollision4pt (const ChTerrain &terrain, const ChVector<> &disc_center, const ChVector<> &disc_normal, double disc_radius, double width, ChCoordsys<> &contact, double &depth, float &mu)
 Perform disc-terrain collision detection considering the curvature of the road surface. More...
 
static bool DiscTerrainCollisionEnvelope (const ChTerrain &terrain, const ChVector<> &disc_center, const ChVector<> &disc_normal, double disc_radius, double width, const ChFunction_Recorder &areaDep, ChCoordsys<> &contact, double &depth, float &mu)
 Collsion algorithm based on a paper of J. 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).
 

Constructor & Destructor Documentation

◆ ChPacejkaTire() [1/2]

chrono::vehicle::ChPacejkaTire::ChPacejkaTire ( const std::string &  name,
const std::string &  pacTire_paramFile 
)

Default constructor for a Pacejka tire.

Construct a Pacejka tire for which the vertical load is calculated internally. The model includes transient slip calculations. chrono can suggest a time step for use with the ODE slips

Parameters
[in]namename of this tire
[in]pacTire_paramFilename of the parameter file

◆ ChPacejkaTire() [2/2]

chrono::vehicle::ChPacejkaTire::ChPacejkaTire ( const std::string &  name,
const std::string &  pacTire_paramFile,
double  Fz_override,
bool  use_transient_slip = true 
)

Construct a Pacejka tire with specified vertical load, for testing purposes.

Parameters
[in]namename of this tire
[in]pacTire_paramFilename of the parameter file
[in]Fz_overrideprescribed vertical load
[in]use_transient_slipindicate if using transient slip model

Member Function Documentation

◆ GetCamberAngle_internal()

double chrono::vehicle::ChPacejkaTire::GetCamberAngle_internal ( ) const
inline

Get the camber angle for the Pacejka tire model (in radians).

The reported value will be the same as that reported by ChTire::GetCamberAngle.

◆ GetLongitudinalSlip_internal()

double chrono::vehicle::ChPacejkaTire::GetLongitudinalSlip_internal ( ) const
inline

Get the tire longitudinal slip computed internally by the Pacejka model.

The reported value will be the same as that reported by ChTire::GetLongitudinalSlip.

◆ GetSlipAngle_internal()

double chrono::vehicle::ChPacejkaTire::GetSlipAngle_internal ( ) const
inline

Get the tire slip angle computed internally by the Pacejka model (in radians).

The reported value will be the same as that reported by ChTire::GetSlipAngle.

◆ getState_from_KAG()

WheelState chrono::vehicle::ChPacejkaTire::getState_from_KAG ( double  kappa,
double  alpha,
double  gamma,
double  Vx 
)

Return orientation, Vx (global) and omega/omega_y (global).

Assumes the tire is going straight forward (global x-dir), and the returned state's orientation yields gamma and alpha, as x and z NASA angles

Parameters
[in]kappa...
[in]alpha...
[in]gamma...
[in]Vxtire forward velocity x-dir

◆ GetTireForce_combinedSlip()

TerrainForce chrono::vehicle::ChPacejkaTire::GetTireForce_combinedSlip ( const bool  local = true) const

Return the reactions for the combined slip EQs, in local or global coords.

Return the reactions for the combined slip EQs, in local or global coordinates.

◆ SetDrivenWheel()

void chrono::vehicle::ChPacejkaTire::SetDrivenWheel ( bool  val)
inline

Specify whether or not the associated wheel is driven.

By default, the wheel is assumed not driven.


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