Description

TMeasy handling tire model.

#include <ChTMeasyTire.h>

Inheritance diagram for chrono::vehicle::ChTMeasyTire:
Collaboration diagram for chrono::vehicle::ChTMeasyTire:

Public Member Functions

 ChTMeasyTire (const std::string &name)
 
virtual std::string GetTemplateName () const override
 Get the name of the vehicle subsystem template.
 
virtual double GetRadius () const override
 Get the tire radius.
 
virtual double GetWidth () const override
 Get the width of the tire.
 
virtual double GetVisualizationWidth () const override
 Get visualization width.
 
double GetSlipAngle_internal () const
 Get the tire slip angle computed internally by the TMsimple model (in radians). More...
 
double GetLongitudinalSlip_internal () const
 Get the tire longitudinal slip computed internally by the TMsimple model. More...
 
double GetTireOmega ()
 
void GuessTruck80Par (unsigned int li, double tireWidth, double ratio, double rimDia, double pinfl_li=1.0, double pinfl_use=1.0, double damping_ratio=0.5)
 Guess Tire Parameters from characteristic truck tire parameter pattern (Ratio = 80%). More...
 
void GuessTruck80Par (double loadForce, double tireWidth, double ratio, double rimDia, double pinfl_li=1.0, double pinfl_use=1.0, double damping_ratio=0.5)
 
void GuessPassCar70Par (unsigned int li, double tireWidth, double ratio, double rimDia, double pinfl_li=1.0, double pinfl_use=1.0, double damping_ratio=0.5)
 Guess Tire Parameters from characteristic passenger car tire parameter pattern (Ratio = 70%). More...
 
void GuessPassCar70Par (double loadForce, double tireWidth, double ratio, double rimDia, double pinfl_li=1.0, double pinfl_use=1.0, double damping_ratio=0.5)
 
void SetVerticalStiffness (double Cz)
 Set vertical tire stiffness as linear function by coefficient [N/m].
 
void SetVerticalStiffness (std::vector< double > &defl, std::vector< double > &frc)
 Set vertical tire stiffness as nonlinear function by coefficients at nominal load 1 [N/m] and nominal load 2 [N/m]. More...
 
void SetFrictionCoefficient (double coef)
 Set the tire reference coefficient of friction.
 
void SetRollingResistanceCoefficient (double coef)
 Set rolling resistance coefficients (default: 0.01).
 
void WritePlots (const std::string &plFileName, const std::string &plTireFormat)
 Generate basic tire plots. More...
 
virtual double GetDeflection () const override
 Get the tire deflection.
 
bool CheckParameters ()
 Simple parameter consistency test.
 
- Public Member Functions inherited from chrono::vehicle::ChForceElementTire
virtual TerrainForce ReportTireForce (ChTerrain *terrain) const override
 Report the tire force and moment. More...
 
virtual TerrainForce ReportTireForceLocal (ChTerrain *terrain, ChCoordsys<> &tire_frame) const override
 Report the tire forces expressed in the tire frame. More...
 
const ContactDataReportTireContactData () const
 Report current tire-terrain contact information. More...
 
void SetVerbose (bool verbose)
 Enable/disable information terminal output (default: false).
 
- 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...
 
void SetPressure (double pressure)
 Set the internal tire pressure [Pa]. More...
 
double GetPressure () const
 Get the internal tire pressure [Pa].
 
virtual double GetTireMass () const =0
 Return the tire mass.
 
virtual ChVector3d 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...
 
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.
 

Static Public Member Functions

static double GetTireMaxLoad (unsigned int li)
 Get maximum tire load from Load Index (LI) in N [0:279].
 
- Static Public Member Functions inherited from chrono::vehicle::ChTire
static ChVector3d 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 ChVector3d &moments, const ChVector3d &products, const ChMatrix33<> &vehicle_rot, const ChMatrix33<> &body_rot)
 Utility function for transforming inertia tensors between centroidal frames. More...
 

Protected Member Functions

virtual void SetTMeasyParams ()=0
 Set the parameters in the TMsimple model.
 
virtual double GetNormalStiffnessForce (double depth) const override final
 Return the vertical tire stiffness contribution to the normal force.
 
virtual double GetNormalDampingForce (double depth, double velocity) const override final
 Return the vertical tire damping contribution to the normal force.
 
virtual void Initialize (std::shared_ptr< ChWheel > wheel) override
 Initialize this tire by associating it to the specified wheel.
 
virtual void Synchronize (double time, const ChTerrain &terrain) override
 Update the state of this tire system at the current time. More...
 
virtual void Advance (double step) override
 Advance the state of this tire by the specified time step.
 
void CombinedCoulombForces (double &fx, double &fy, double fz, double muscale)
 
void tmxy_combined (double &f, double &fos, double s, double df0, double sm, double fm, double ss, double fs)
 
double AlignmentTorque (double fy)
 
double InterpL (double w1, double w2)
 
double InterpQ (double w1, double w2)
 
- Protected Member Functions inherited from chrono::vehicle::ChForceElementTire
 ChForceElementTire (const std::string &name)
 Construct a tire with the specified name.
 
virtual TerrainForce GetTireForce () const override
 Get the tire force and moment. 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.
 
- 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< ChVisualShapeTriangleMeshAddVisualizationMesh (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 (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

bool m_use_startup_transition
 
double m_time
 
double m_begin_start_transition
 
double m_end_start_transition
 
double m_vnum
 
double m_unloaded_radius
 reference tire radius
 
double m_width
 tire width
 
double m_rim_radius
 tire rim radius
 
double m_bottom_radius
 radius where tire bottoming begins
 
double m_bottom_stiffness
 stiffness of the tire/bottom contact
 
double m_rolling_resistance
 actual rolling friction coeff
 
double m_d1
 polynomial coefficient for stiffness interpolation, linear
 
double m_d2
 polynomial coefficient for stiffness interpolation, quadratic
 
double m_vcoulomb
 
double m_frblend_begin
 
double m_frblend_end
 
VehicleSide m_measured_side
 
TMeasyCoeff m_par
 
TireStates m_states
 
- Protected Attributes inherited from chrono::vehicle::ChForceElementTire
ContactData m_data
 tire-terrain collision information
 
TerrainForce m_tireforce
 tire forces (in tire contact frame)
 
ChFunctionInterp m_areaDep
 lookup table for estimation of penetration depth from intersection area
 
std::shared_ptr< ChVisualShapem_cyl_shape
 visualization cylinder asset
 
bool m_verbose
 verbose output
 
- Protected Attributes inherited from chrono::vehicle::ChTire
std::shared_ptr< ChWheelm_wheel
 associated wheel subsystem
 
double m_stepsize
 tire integration step size (if applicable)
 
double m_pressure
 internal tire pressure
 
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 Protected Member Functions inherited from chrono::vehicle::ChTire
static bool DiscTerrainCollision (CollisionType method, const ChTerrain &terrain, const ChVector3d &disc_center, const ChVector3d &disc_normal, double disc_radius, double width, const ChFunctionInterp &areaDep, ChCoordsys<> &contact, double &depth, float &mu)
 Perform disc-terrain collision detection, using the specified method. More...
 
static void ConstructAreaDepthTable (double disc_radius, ChFunctionInterp &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 ChVector3d &disc_center, const ChVector3d &disc_normal, double disc_radius, ChCoordsys<> &contact, double &depth, float &mu)
 Perform disc-terrain collision detection. More...
 
static bool DiscTerrainCollision4pt (const ChTerrain &terrain, const ChVector3d &disc_center, const ChVector3d &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 ChVector3d &disc_center, const ChVector3d &disc_normal, double disc_radius, double width, const ChFunctionInterp &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).
 

Member Function Documentation

◆ GetLongitudinalSlip_internal()

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

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

The reported value will be similar to that reported by ChTire::GetLongitudinalSlip.

◆ GetSlipAngle_internal()

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

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

The reported value will be similar to that reported by ChTire::GetSlipAngle.

◆ GuessPassCar70Par() [1/2]

void chrono::vehicle::ChTMeasyTire::GuessPassCar70Par ( double  loadForce,
double  tireWidth,
double  ratio,
double  rimDia,
double  pinfl_li = 1.0,
double  pinfl_use = 1.0,
double  damping_ratio = 0.5 
)
Parameters
loadForcetire nominal load force [N]
tireWidthtire width [m]
ratiouse 0.75 meaning 75%
rimDiarim diameter [m]
pinfl_liinflation pressure at load index
pinfl_useinflation pressure in this configuration
damping_ratioscaling factor for normal damping coefficient

◆ GuessPassCar70Par() [2/2]

void chrono::vehicle::ChTMeasyTire::GuessPassCar70Par ( unsigned int  li,
double  tireWidth,
double  ratio,
double  rimDia,
double  pinfl_li = 1.0,
double  pinfl_use = 1.0,
double  damping_ratio = 0.5 
)

Guess Tire Parameters from characteristic passenger car tire parameter pattern (Ratio = 70%).

Parameters
litire load index
tireWidthtire width [m]
ratiouse 0.75 meaning 75%
rimDiarim diameter [m]
pinfl_liinflation pressure at load index
pinfl_useinflation pressure in this configuration
damping_ratioscaling factor for normal damping coefficient

◆ GuessTruck80Par() [1/2]

void chrono::vehicle::ChTMeasyTire::GuessTruck80Par ( double  loadForce,
double  tireWidth,
double  ratio,
double  rimDia,
double  pinfl_li = 1.0,
double  pinfl_use = 1.0,
double  damping_ratio = 0.5 
)
Parameters
loadForcetire nominal load force [N]
tireWidthtire width [m]
ratiouse 0.75 meaning 75%
rimDiarim diameter [m]
pinfl_liinflation pressure at load index
pinfl_useinflation pressure in this configuration
damping_ratioscaling factor for normal damping coefficient

◆ GuessTruck80Par() [2/2]

void chrono::vehicle::ChTMeasyTire::GuessTruck80Par ( unsigned int  li,
double  tireWidth,
double  ratio,
double  rimDia,
double  pinfl_li = 1.0,
double  pinfl_use = 1.0,
double  damping_ratio = 0.5 
)

Guess Tire Parameters from characteristic truck tire parameter pattern (Ratio = 80%).

Parameters
litire load index
tireWidthtire width [m]
ratiouse 0.75 meaning 75%
rimDiarim diameter [m]
pinfl_liinflation pressure at load index
pinfl_useinflation pressure in this configuration
damping_ratioscaling factor for normal damping coefficient

◆ SetVerticalStiffness()

void chrono::vehicle::ChTMeasyTire::SetVerticalStiffness ( std::vector< double > &  defl,
std::vector< double > &  frc 
)

Set vertical tire stiffness as nonlinear function by coefficients at nominal load 1 [N/m] and nominal load 2 [N/m].

void SetVerticalStiffness(double Cz1, double Cz2); Set vertical tire stiffness as nonlinear function by calculation from tire test data (least squares).

◆ Synchronize()

void chrono::vehicle::ChTMeasyTire::Synchronize ( double  time,
const ChTerrain terrain 
)
overrideprotectedvirtual

Update the state of this tire system at the current time.

Parameters
[in]timecurrent time
[in]terrainreference to the terrain system

Reimplemented from chrono::vehicle::ChTire.

◆ WritePlots()

void chrono::vehicle::ChTMeasyTire::WritePlots ( const std::string &  plFileName,
const std::string &  plTireFormat 
)

Generate basic tire plots.

This function creates a Gnuplot script file with the specified name.


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