Description

Tire model based on LuGre friction model.

#include <ChLugreTire.h>

Inheritance diagram for chrono::vehicle::ChLugreTire:
Collaboration diagram for chrono::vehicle::ChLugreTire:

Public Member Functions

 ChLugreTire (const std::string &name)
 
virtual std::string GetTemplateName () const override
 Get the name of the vehicle subsystem template.
 
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.
 
double GetWidth () const
 Get the tire width. More...
 
virtual TerrainForce ReportTireForce (ChTerrain *terrain) const override
 Report the tire force and moment.
 
- Public Member Functions inherited from chrono::vehicle::ChTire
 ChTire (const std::string &name)
 
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 GetRadius () const =0
 Get the tire radius.
 
virtual double GetMass () const =0
 Get the tire mass. More...
 
virtual double ReportMass () const
 Report the tire mass. More...
 
virtual ChVector GetInertia () const =0
 Get the tire moments of inertia. More...
 
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.
 
- Public Member Functions inherited from chrono::vehicle::ChPart
 ChPart (const std::string &name)
 Construct a vehicle subsystem with the specified name. More...
 
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.
 
void SetVisualizationType (VisualizationType vis)
 Set the visualization mode for this subsystem.
 
void SetContactFrictionCoefficient (float friction_coefficient)
 Set coefficient of friction. More...
 
void SetContactRestitutionCoefficient (float restitution_coefficient)
 Set coefficient of restitution. More...
 
void SetContactMaterialProperties (float young_modulus, float poisson_ratio)
 Set contact material properties. More...
 
void SetContactMaterialCoefficients (float kn, float gn, float kt, float gt)
 Set contact material coefficients. More...
 
float GetCoefficientFriction () const
 Get coefficient of friction for contact material.
 
float GetCoefficientRestitution () const
 Get coefficient of restitution for contact material.
 
float GetYoungModulus () const
 Get Young's modulus of elasticity for contact material.
 
float GetPoissonRatio () const
 Get Poisson ratio for contact material.
 
float GetKn () const
 Get normal stiffness coefficient for contact material.
 
float GetKt () const
 Get tangential stiffness coefficient for contact material.
 
float GetGn () const
 Get normal viscous damping coefficient for contact material.
 
float GetGt () const
 Get tangential viscous damping coefficient for contact material.
 
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

virtual int GetNumDiscs () const =0
 Return the number of discs used to model this tire.
 
virtual const double * GetDiscLocations () const =0
 Return the lateral disc locations. More...
 
virtual double GetNormalStiffness () const =0
 Return the vertical tire stiffness (for normal force calculation).
 
virtual double GetNormalDamping () const =0
 Return the vertical tire damping coefficient (for normal force calculation).
 
virtual void SetLugreParams ()=0
 Set the parameters in the LuGre friction model.
 
- Protected Member Functions inherited from chrono::vehicle::ChTire
void CalculateKinematics (double time, const WheelState &wheel_state, const ChTerrain &terrain)
 Calculate kinematics quantities based on the given state of the associated wheel body. More...
 
double GetOffset () const
 Get offset from spindle center. More...
 
- Protected Member Functions inherited from chrono::vehicle::ChPart
virtual void Create (const rapidjson::Document &d)
 Create a vehicle subsystem from JSON data. More...
 

Protected Attributes

double m_sigma0 [2]
 Lugre friction model parameters (longitudinal/lateral)
 
double m_sigma1 [2]
 
double m_sigma2 [2]
 
double m_Fc [2]
 
double m_Fs [2]
 
double m_vs [2]
 Stribeck velocity.
 
- 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
 
- Protected Attributes inherited from chrono::vehicle::ChPart
std::string m_name
 subsystem name
 
bool m_output
 specifies whether or not output is generated for this subsystem
 
float m_friction
 contact coefficient of friction
 
float m_restitution
 contact coefficient of restitution
 
float m_young_modulus
 contact material Young modulus
 
float m_poisson_ratio
 contact material Poisson ratio
 
float m_kn
 normal contact stiffness
 
float m_gn
 normal contact damping
 
float m_kt
 tangential contact stiffness
 
float m_gt
 tangential contact damping
 

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 (const ChTerrain &terrain, const ChVector<> &disc_center, const ChVector<> &disc_normal, double disc_radius, ChCoordsys<> &contact, double &depth)
 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, double &camber_angle)
 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, const ChFunction_Recorder &areaDep, ChCoordsys<> &contact, double &depth)
 Collsion algorithm based on a paper of J. 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 Protected Member Functions inherited from chrono::vehicle::ChPart
static void ExportBodyList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChBody >> bodies)
 Export the list of bodies to the specified JSON document.
 
static void ExportShaftList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChShaft >> shafts)
 Export the list of shafts to the specified JSON document.
 
static void ExportJointList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLink >> joints)
 Export the list of joints to the specified JSON document.
 
static void ExportCouplesList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChShaftsCouple >> couples)
 Export the list of shaft couples to the specified JSON document.
 
static void ExportMarkerList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChMarker >> markers)
 Export the list of markers to the specified JSON document.
 
static void ExportLinSpringList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLinkSpringCB >> springs)
 Export the list of translational springs to the specified JSON document.
 
static void ExportRotSpringList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLinkRotSpringCB >> springs)
 Export the list of rotational springs to the specified JSON document.
 
static void ExportBodyLoadList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLoadBodyBody >> loads)
 Export the list of body-body loads to the specified JSON document.
 

Member Function Documentation

virtual const double* chrono::vehicle::ChLugreTire::GetDiscLocations ( ) const
protectedpure virtual

Return the lateral disc locations.

These locations are relative to the tire center.

Implemented in chrono::vehicle::hmmwv::HMMWV_LugreTire, and chrono::vehicle::LugreTire.

double chrono::vehicle::ChLugreTire::GetWidth ( ) const

Get the tire width.

This is just an approximation of a tire width.