Description

Base class for a Rack-Pinion steering subsystem.

Derived from ChSteering, but still an abstract base class.

The steering subsystem is modeled with respect to a right-handed frame with with X pointing towards the front, Y to the left, and Z up (ISO standard). The steering link translates along the Y axis. We do not explicitly model the pinion but instead use the implied rack-pinion constraint to calculate the rack displacement from a given pinion rotation angle.

#include <ChRackPinion.h>

Inheritance diagram for chrono::vehicle::ChRackPinion:
Collaboration diagram for chrono::vehicle::ChRackPinion:

Public Member Functions

 ChRackPinion (const std::string &name)
 Construct a rack-pinion steering mechanism with given base name. More...
 
virtual std::string GetTemplateName () const override
 Get the name of the vehicle subsystem template.
 
virtual void Initialize (std::shared_ptr< ChChassis > chassis, const ChVector<> &location, const ChQuaternion<> &rotation) override
 Initialize this steering subsystem. More...
 
virtual void AddVisualizationAssets (VisualizationType vis) override
 Add visualization assets for the steering subsystem. More...
 
virtual void RemoveVisualizationAssets () override
 Remove visualization assets for the steering subsystem.
 
virtual void Synchronize (double time, double steering) override
 Update the state of this steering subsystem at the current time. More...
 
virtual void LogConstraintViolations () override
 Log current constraint violations.
 
- Public Member Functions inherited from chrono::vehicle::ChSteering
const ChFrameGetRelTransform () const
 Get the frame of the steering subsystem relative to the associated chassis reference frame.
 
std::shared_ptr< ChBodyGetSteeringLink () const
 Get a handle to the main link of the steering subsystems. 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.
 
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.
 

Protected Member Functions

virtual void InitializeInertiaProperties () override
 Initialize subsystem inertia properties. More...
 
virtual void UpdateInertiaProperties () override
 Update subsystem inertia properties. More...
 
virtual double GetSteeringLinkMass () const =0
 Return the mass of the steering link.
 
virtual ChVector GetSteeringLinkInertia () const =0
 Return the moments of inertia of the steering link.
 
virtual double GetSteeringLinkCOM () const =0
 Return the steering link COM offset in Y direction (positive to the left).
 
virtual double GetSteeringLinkRadius () const =0
 Return the radius of the steering link (visualization only).
 
virtual double GetSteeringLinkLength () const =0
 Return the length of the steering link (visualization only).
 
virtual double GetPinionRadius () const =0
 Return the radius of the pinion.
 
virtual double GetMaxAngle () const =0
 Return the maximum rotation angle of the pinion (in either direction).
 
virtual void ExportComponentList (rapidjson::Document &jsonDocument) const override
 Export this subsystem's component list to the specified JSON object. More...
 
virtual void Output (ChVehicleOutput &database) const override
 Output data for this subsystem's component list to the specified database.
 
- Protected Member Functions inherited from chrono::vehicle::ChSteering
 ChSteering (const std::string &name)
 Construct a steering subsystem with given name.
 
- 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...
 
virtual void Create (const rapidjson::Document &d)
 Create a vehicle subsystem from JSON data. More...
 

Protected Attributes

std::shared_ptr< ChLinkLockPrismaticm_prismatic
 handle to the prismatic joint chassis-link
 
std::shared_ptr< ChLinkLinActuatorm_actuator
 handle to the linear actuator on steering link
 
- Protected Attributes inherited from chrono::vehicle::ChSteering
ChFrame m_rel_xform
 location and orientation relative to associated chassis
 
std::shared_ptr< ChBodym_link
 handle to the main steering link
 
- 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
 
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

- 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::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< ChLinkTSDA >> springs)
 Export the list of translational springs to the specified JSON document.
 
static void ExportRotSpringList (rapidjson::Document &jsonDocument, std::vector< std::shared_ptr< ChLinkRSDA >> 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.
 
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

◆ ChRackPinion()

chrono::vehicle::ChRackPinion::ChRackPinion ( const std::string &  name)

Construct a rack-pinion steering mechanism with given base name.

Parameters
[in]namename of the subsystem

Member Function Documentation

◆ AddVisualizationAssets()

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

Add visualization assets for the steering subsystem.

This default implementation uses primitives.

Reimplemented from chrono::vehicle::ChPart.

◆ ExportComponentList()

void chrono::vehicle::ChRackPinion::ExportComponentList ( rapidjson::Document &  jsonDocument) const
overrideprotectedvirtual

Export this subsystem's component list to the specified JSON object.

Derived classes should override this function and first invoke the base class implementation, followed by calls to the various static Export***List functions, as appropriate.

Reimplemented from chrono::vehicle::ChPart.

◆ Initialize()

void chrono::vehicle::ChRackPinion::Initialize ( std::shared_ptr< ChChassis chassis,
const ChVector<> &  location,
const ChQuaternion<> &  rotation 
)
overridevirtual

Initialize this steering subsystem.

The steering subsystem is initialized by attaching it to the specified chassis at the specified location (with respect to and expressed in the reference frame of the chassis) and with specified orientation (with respect to the chassis reference frame).

Parameters
[in]chassisassociated chassis subsystem
[in]locationlocation relative to the chassis frame
[in]rotationorientation relative to the chassis frame

Implements chrono::vehicle::ChSteering.

◆ InitializeInertiaProperties()

void chrono::vehicle::ChRackPinion::InitializeInertiaProperties ( )
overrideprotectedvirtual

Initialize subsystem inertia properties.

Derived classes must override this function and set the subsystem mass (m_mass) and, if constant, the subsystem COM frame and its inertia tensor. This function is called during initialization of the vehicle system.

Implements chrono::vehicle::ChPart.

◆ Synchronize()

void chrono::vehicle::ChRackPinion::Synchronize ( double  time,
double  steering 
)
overridevirtual

Update the state of this steering subsystem at the current time.

The steering subsystem is provided the current steering driver input (a value between -1 and +1). Positive steering input indicates steering to the left. This function is called during the vehicle update.

Parameters
[in]timecurrent time
[in]steeringcurrent steering input [-1,+1]

Implements chrono::vehicle::ChSteering.

◆ UpdateInertiaProperties()

void chrono::vehicle::ChRackPinion::UpdateInertiaProperties ( )
overrideprotectedvirtual

Update subsystem inertia properties.

Derived classes must override this function and set the global subsystem transform (m_xform) and, unless constant, the subsystem COM frame (m_com) and its inertia tensor (m_inertia). Calculate the current inertia properties and global frame of this subsystem. This function is called every time the state of the vehicle system is advanced in time.

Implements chrono::vehicle::ChPart.


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