Description

Base class for an idler subsystem.

An idler consists of the idler wheel and a connecting body. The idler wheel is connected through a revolute joint to the connecting body which in turn is connected to the chassis through a translational joint. A linear actuator acts as a tensioner.

#include <ChIdler.h>

Inheritance diagram for chrono::vehicle::ChIdler:
Collaboration diagram for chrono::vehicle::ChIdler:

Public Member Functions

 ChIdler (const std::string &name)
 
virtual GuidePinType GetType () const =0
 Return the type of track shoe consistent with this idler.
 
std::shared_ptr< ChBodyGetWheelBody () const
 Get a handle to the road wheel body.
 
std::shared_ptr
< ChLinkLockRevolute
GetRevolute () const
 Get a handle to the revolute joint.
 
virtual double GetWheelRadius () const =0
 Get the radius of the idler wheel.
 
void SetCollide (bool val)
 Turn on/off collision flag for the idler wheel.
 
virtual double GetMass () const
 Get the mass of the idler subsystem.
 
virtual void Initialize (std::shared_ptr< ChBodyAuxRef > chassis, const ChVector<> &location)
 Initialize this idler subsystem. More...
 
virtual void AddVisualizationAssets (VisualizationType vis) override
 Add visualization assets for the idler subsystem. More...
 
virtual void RemoveVisualizationAssets () override
 Remove visualization assets for the idler subsystem. 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.
 
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 Types

enum  PointId {
  WHEEL, CARRIER, CARRIER_CHASSIS, TSDA_CARRIER,
  TSDA_CHASSIS, NUM_POINTS
}
 Identifiers for the various hardpoints. More...
 

Protected Member Functions

virtual const ChVector GetLocation (PointId which)=0
 Return the location of the specified hardpoint. More...
 
virtual double GetWheelMass () const =0
 Return the mass of the idler wheel body.
 
virtual const ChVectorGetWheelInertia ()=0
 Return the moments of inertia of the idler wheel body.
 
virtual double GetCarrierMass () const =0
 Return the mass of the carrier body.
 
virtual const ChVectorGetCarrierInertia ()=0
 Return the moments of inertia of the carrier body.
 
virtual double GetCarrierVisRadius () const =0
 Return a visualization radius for the carrier body.
 
virtual double GetPrismaticPitchAngle () const =0
 Return the pitch angle of the prismatic joint.
 
virtual ChSpringForceCallbackGetTensionerForceCallback () const =0
 Return the callback function for spring force.
 
virtual double GetTensionerFreeLength () const =0
 Return the free length for the tensioner spring.
 

Protected Attributes

std::shared_ptr< ChBodym_wheel
 handle to the idler wheel body
 
std::shared_ptr< ChBodym_carrier
 handle to the carrier body
 
std::shared_ptr
< ChLinkLockRevolute
m_revolute
 handle to wheel-carrier revolute joint
 
std::shared_ptr
< ChLinkLockPrismatic
m_prismatic
 handle to carrier-chassis translational joint
 
std::shared_ptr< ChLinkSpringCBm_tensioner
 handle to the TSDA tensioner element
 
- 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
 

Member Enumeration Documentation

Identifiers for the various hardpoints.

Enumerator
WHEEL 

idler wheel location

CARRIER 

carrier location

CARRIER_CHASSIS 

carrier, connection to chassis (translational)

TSDA_CARRIER 

TSDA connection to carrier.

TSDA_CHASSIS 

TSDA connection to chassis.

Constructor & Destructor Documentation

chrono::vehicle::ChIdler::ChIdler ( const std::string &  name)
Parameters
[in]namename of the subsystem

Member Function Documentation

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

Add visualization assets for the idler subsystem.

This default implementation adds assets to the carrier body.

Reimplemented from chrono::vehicle::ChPart.

Reimplemented in chrono::vehicle::DoubleIdler, chrono::vehicle::SingleIdler, chrono::vehicle::ChDoubleIdler, and chrono::vehicle::ChSingleIdler.

virtual const ChVector chrono::vehicle::ChIdler::GetLocation ( PointId  which)
protectedpure virtual

Return the location of the specified hardpoint.

The returned location must be expressed in the idler subsystem reference frame.

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

Initialize this idler subsystem.

The idler 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 idler subsystem reference frame is always aligned with the chassis reference frame. A derived idler subsystem template class must extend this default implementation and specify contact geometry for the idler wheel.

Parameters
[in]chassishandle to the chassis body
[in]locationlocation relative to the chassis frame

Reimplemented in chrono::vehicle::ChDoubleIdler, and chrono::vehicle::ChSingleIdler.

void chrono::vehicle::ChIdler::RemoveVisualizationAssets ( )
overridevirtual

Remove visualization assets for the idler subsystem.

This default implementation removes the assets from the carrier body.

Reimplemented from chrono::vehicle::ChPart.

Reimplemented in chrono::vehicle::ChDoubleIdler, and chrono::vehicle::ChSingleIdler.