Description

Definition of a track assembly.

A track assembly consists of a sprocket, an idler (with tensioner mechanism), a set of rollers, a set of suspensions (road-wheel assemblies), and a collection of track shoes.

#include <ChTrackAssembly.h>

Inheritance diagram for chrono::vehicle::ChTrackAssembly:
Collaboration diagram for chrono::vehicle::ChTrackAssembly:

Public Member Functions

VehicleSide GetVehicleSide () const
 Return the vehicle side for this track assembly.
 
size_t GetNumRoadWheelAssemblies () const
 Get the number of suspensions.
 
size_t GetNumRollers () const
 Get the number of rollers.
 
virtual size_t GetNumTrackShoes () const =0
 Get the number of track shoes.
 
virtual std::shared_ptr
< ChSprocket
GetSprocket () const =0
 Get a handle to the sprocket.
 
std::shared_ptr< ChIdlerGetIdler () const
 Get a handle to the idler subsystem.
 
std::shared_ptr< ChTrackBrakeGetBrake () const
 Get a handle to the brake subsystem.
 
std::shared_ptr
< ChRoadWheelAssembly
GetRoadWheelAssembly (size_t id) const
 Get a handle to the specified suspension subsystem.
 
std::shared_ptr< ChRollerGetRoller (size_t id) const
 Get a handle to the specified roller subsystem.
 
std::shared_ptr< ChRoadWheelGetRoadWheel (size_t id) const
 Get a handle to the specified road wheel subsystem.
 
virtual std::shared_ptr
< ChTrackShoe
GetTrackShoe (size_t id) const =0
 Get a handle to the specified track shoe subsystem.
 
const ChVectorGetTrackShoePos (size_t id) const
 Get the global location of the specified track shoe. More...
 
const ChQuaternionGetTrackShoeRot (size_t id) const
 Get the orientation of the the specified track shoe. More...
 
const ChVectorGetTrackShoeLinVel (size_t id) const
 Get the linear velocity of the specified track shoe. More...
 
ChVector GetTrackShoeAngVel (size_t id) const
 Get the angular velocity of the the specified track shoe. More...
 
BodyState GetTrackShoeState (size_t id) const
 Get the complete state for the specified track shoe. More...
 
void GetTrackShoeStates (BodyStates &states) const
 Get the complete states for all track shoes. More...
 
double GetMass () const
 Get the total mass of the track assembly. More...
 
virtual const ChVector GetSprocketLocation () const =0
 Get the relative location of the sprocket subsystem. More...
 
virtual const ChVector GetIdlerLocation () const =0
 Get the relative location of the idler subsystem. More...
 
virtual const ChVector GetRoadWhelAssemblyLocation (int which) const =0
 Get the relative location of the specified suspension subsystem. More...
 
virtual const ChVector GetRollerLocation (int which) const
 Get the relative location of the specified roller subsystem. More...
 
void Initialize (std::shared_ptr< ChBodyAuxRef > chassis, const ChVector<> &location)
 Initialize this track assembly subsystem. More...
 
void SetSprocketVisualizationType (VisualizationType vis)
 Set visualization type for the sprocket subsystem.
 
void SetIdlerVisualizationType (VisualizationType vis)
 
void SetRoadWheelAssemblyVisualizationType (VisualizationType vis)
 Set visualization type for the suspension subsystems.
 
void SetRoadWheelVisualizationType (VisualizationType vis)
 Set visualization type for the road-wheel subsystems.
 
void SetRollerVisualizationType (VisualizationType vis)
 Set visualization type for the roller subsystems.
 
void SetTrackShoeVisualizationType (VisualizationType vis)
 Set visualization type for the track shoe subsystems.
 
void Synchronize (double time, double braking, const TrackShoeForces &shoe_forces)
 Update the state of this track assembly at the current time. More...
 
void LogConstraintViolations ()
 Log current constraint violations.
 
- 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 track shoe subsystem.
 
void SetName (const std::string &name)
 Set the name identifier for this track shoe subsystem.
 
void SetVisualizationType (VisualizationType vis)
 Set the visualization mode for this subsystem.
 
virtual void AddVisualizationAssets (VisualizationType vis)
 Add visualization assets to this subsystem, for the specified visualization mode.
 
virtual void RemoveVisualizationAssets ()
 Remove all visualization assets from 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.
 

Protected Member Functions

 ChTrackAssembly (const std::string &name, VehicleSide side)
 
virtual bool Assemble (std::shared_ptr< ChBodyAuxRef > chassis)=0
 Assemble track shoes over wheels. More...
 

Protected Attributes

VehicleSide m_side
 assembly on left/right vehicle side
 
std::shared_ptr< ChIdlerm_idler
 idler (and tensioner) subsystem
 
std::shared_ptr< ChTrackBrakem_brake
 sprocket brake
 
ChRoadWheelAssemblyList m_suspensions
 road-wheel assemblies
 
ChRollerList m_rollers
 roller subsystems
 
- Protected Attributes inherited from chrono::vehicle::ChPart
std::string m_name
 
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

- 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...
 

Constructor & Destructor Documentation

chrono::vehicle::ChTrackAssembly::ChTrackAssembly ( const std::string &  name,
VehicleSide  side 
)
protected
Parameters
[in]namename of the subsystem
[in]sideassembly on left/right vehicle side

Member Function Documentation

virtual bool chrono::vehicle::ChTrackAssembly::Assemble ( std::shared_ptr< ChBodyAuxRef chassis)
protectedpure virtual

Assemble track shoes over wheels.

Return true if the track shoes were initialized in a counter clockwise direction and false otherwise.

virtual const ChVector chrono::vehicle::ChTrackAssembly::GetIdlerLocation ( ) const
pure virtual

Get the relative location of the idler subsystem.

The track assembly reference frame is ISO, with origin at the sprocket center.

Implemented in chrono::vehicle::TrackAssemblyDoublePin, chrono::vehicle::TrackAssemblySinglePin, chrono::vehicle::m113::M113a_TrackAssemblySinglePin, chrono::vehicle::m113::M113_TrackAssemblyDoublePin, and chrono::vehicle::m113::M113_TrackAssemblySinglePin.

double chrono::vehicle::ChTrackAssembly::GetMass ( ) const

Get the total mass of the track assembly.

This includes the masses of the sprocket, idler, suspensions, and track shoes.

virtual const ChVector chrono::vehicle::ChTrackAssembly::GetRoadWhelAssemblyLocation ( int  which) const
pure virtual

Get the relative location of the specified suspension subsystem.

The track assembly reference frame is ISO, with origin at the sprocket center.

Implemented in chrono::vehicle::TrackAssemblyDoublePin, chrono::vehicle::TrackAssemblySinglePin, chrono::vehicle::m113::M113a_TrackAssemblySinglePin, chrono::vehicle::m113::M113_TrackAssemblyDoublePin, and chrono::vehicle::m113::M113_TrackAssemblySinglePin.

virtual const ChVector chrono::vehicle::ChTrackAssembly::GetRollerLocation ( int  which) const
virtual

Get the relative location of the specified roller subsystem.

The track assembly reference frame is ISO, with origin at the sprocket center.

Reimplemented in chrono::vehicle::TrackAssemblyDoublePin, and chrono::vehicle::TrackAssemblySinglePin.

virtual const ChVector chrono::vehicle::ChTrackAssembly::GetSprocketLocation ( ) const
pure virtual

Get the relative location of the sprocket subsystem.

The track assembly reference frame is ISO, with origin at the sprocket center.

Implemented in chrono::vehicle::TrackAssemblyDoublePin, chrono::vehicle::TrackAssemblySinglePin, chrono::vehicle::m113::M113a_TrackAssemblySinglePin, chrono::vehicle::m113::M113_TrackAssemblyDoublePin, and chrono::vehicle::m113::M113_TrackAssemblySinglePin.

ChVector chrono::vehicle::ChTrackAssembly::GetTrackShoeAngVel ( size_t  id) const

Get the angular velocity of the the specified track shoe.

Return the angular velocity of the shoe body frame, expressed in the global reference frame.

const ChVector& chrono::vehicle::ChTrackAssembly::GetTrackShoeLinVel ( size_t  id) const

Get the linear velocity of the specified track shoe.

Return the linear velocity of the shoe body center, expressed in the global reference frame.

const ChVector& chrono::vehicle::ChTrackAssembly::GetTrackShoePos ( size_t  id) const

Get the global location of the specified track shoe.

The returned location is that of the shoe body in the track shoe subsystem.

const ChQuaternion& chrono::vehicle::ChTrackAssembly::GetTrackShoeRot ( size_t  id) const

Get the orientation of the the specified track shoe.

The track shoe body orientation is returned as a quaternion representing a rotation with respect to the global reference frame. This is the orientation of the shoe body in the track shoe subsystem.

BodyState chrono::vehicle::ChTrackAssembly::GetTrackShoeState ( size_t  id) const

Get the complete state for the specified track shoe.

This includes the location, orientation, linear and angular velocities, all expressed in the global reference frame.

void chrono::vehicle::ChTrackAssembly::GetTrackShoeStates ( BodyStates states) const

Get the complete states for all track shoes.

These include the locations, orientations, linear and angular velocities for all track shoes in this track assembly, all expressed in the global reference frame. It is assumed that the vector of body states was properly sized.

void chrono::vehicle::ChTrackAssembly::Initialize ( std::shared_ptr< ChBodyAuxRef chassis,
const ChVector<> &  location 
)

Initialize this track assembly subsystem.

The subsystem is initialized by attaching it to the specified chassis body at the specified location (with respect to and expressed in the reference frame of the chassis). It is assumed that the track assembly reference frame is always aligned with the chassis reference frame.

Parameters
[in]chassishandle to the chassis body
[in]locationlocation relative to the chassis frame
void chrono::vehicle::ChTrackAssembly::Synchronize ( double  time,
double  braking,
const TrackShoeForces shoe_forces 
)

Update the state of this track assembly at the current time.

Parameters
[in]timecurrent time
[in]brakingbraking driver input
[in]shoe_forcesvector of tire force structures