Description

Base class for a double-A arm suspension modeled with bodies and constraints.

Derived from ChSuspension, but still an abstract base class.

The suspension subsystem is modeled with respect to a right-handed frame, with X pointing towards the front, Y to the left, and Z up (ISO standard). The suspension reference frame is assumed to be always aligned with that of the vehicle. When attached to a chassis, only an offset is provided.

All point locations are assumed to be given for the left half of the suspension and will be mirrored (reflecting the y coordinates) to construct the right side.

#include <ChDoubleWishbone.h>

Inheritance diagram for chrono::vehicle::ChDoubleWishbone:
Collaboration diagram for chrono::vehicle::ChDoubleWishbone:

Public Member Functions

virtual std::string GetTemplateName () const override
 Get the name of the vehicle subsystem template.
 
virtual bool IsSteerable () const final override
 Specify whether or not this suspension can be steered.
 
virtual bool IsIndependent () const final override
 Specify whether or not this is an independent suspension.
 
virtual void Initialize (std::shared_ptr< ChChassis > chassis, std::shared_ptr< ChSubchassis > subchassis, std::shared_ptr< ChSteering > steering, const ChVector<> &location, double left_ang_vel=0, double right_ang_vel=0) override
 Initialize this suspension subsystem. More...
 
virtual void AddVisualizationAssets (VisualizationType vis) override
 Add visualization assets for the suspension subsystem. More...
 
virtual void RemoveVisualizationAssets () override
 Remove visualization assets for the suspension subsystem.
 
virtual double GetMass () const override
 Get the total mass of the suspension subsystem.
 
virtual ChVector GetCOMPos () const override
 Get the current global COM location of the suspension subsystem.
 
virtual double GetTrack () override
 Get the wheel track for the suspension subsystem.
 
std::shared_ptr< ChLinkTSDAGetSpring (VehicleSide side) const
 Get a handle to the specified spring element.
 
std::shared_ptr< ChLinkTSDAGetShock (VehicleSide side) const
 Get a handle to the specified shock (damper) element.
 
virtual ChSuspension::Force ReportSuspensionForce (VehicleSide side) const override
 Return current suspension forces (spring and shock) on the specified side.
 
double GetSpringForce (VehicleSide side) const
 Get the force in the spring element.
 
double GetSpringLength (VehicleSide side) const
 Get the current length of the spring element.
 
double GetSpringDeformation (VehicleSide side) const
 Get the current deformation of the spring element.
 
double GetShockForce (VehicleSide side) const
 Get the force in the shock (damper) element.
 
double GetShockLength (VehicleSide side) const
 Get the current length of the shock (damper) element.
 
double GetShockVelocity (VehicleSide side) const
 Get the current deformation velocity of the shock (damper) element.
 
ChVector Get_LCA_sph_pos (VehicleSide side)
 Global coordinates, LCA ball joint position.
 
ChVector Get_UCA_sph_pos (VehicleSide side)
 Global coordinates, UCA ball joint position.
 
virtual void LogConstraintViolations (VehicleSide side) override
 Log current constraint violations.
 
virtual std::shared_ptr< ChBodyGetAntirollBody (VehicleSide side) const override
 Specify the suspension body on the specified side to attach a possible antirollbar subsystem. More...
 
void LogHardpointLocations (const ChVector<> &ref, bool inches=false)
 Log the locations of all hardpoints. More...
 
- Public Member Functions inherited from chrono::vehicle::ChSuspension
 ChSuspension (const std::string &name)
 
const ChVectorGetLocation () const
 Get the location of the suspension subsystem relative to the chassis reference frame. More...
 
std::shared_ptr< ChBodyGetSpindle (VehicleSide side) const
 Get a handle to the spindle body on the specified side.
 
std::shared_ptr< ChShaftGetAxle (VehicleSide side) const
 Get a handle to the axle shaft on the specified side.
 
std::shared_ptr< ChLinkLockRevoluteGetRevolute (VehicleSide side) const
 Get a handle to the revolute joint on the specified side.
 
const ChVectorGetSpindlePos (VehicleSide side) const
 Get the global location of the spindle on the specified side.
 
ChQuaternion GetSpindleRot (VehicleSide side) const
 Get the orientation of the spindle body on the specified side. More...
 
const ChVectorGetSpindleLinVel (VehicleSide side) const
 Get the linear velocity of the spindle body on the specified side. More...
 
ChVector GetSpindleAngVel (VehicleSide side) const
 Get the angular velocity of the spindle body on the specified side. More...
 
double GetAxleSpeed (VehicleSide side) const
 Get the angular speed of the axle on the specified side.
 
void Synchronize ()
 Synchronize this suspension subsystem. More...
 
void ApplyAxleTorque (VehicleSide side, double torque)
 Apply the provided motor torque. More...
 
virtual double getSpindleRadius () const =0
 Return the radius of the spindle body (visualization only).
 
virtual double getSpindleWidth () const =0
 Return the width of the spindle body (visualization only).
 
virtual std::shared_ptr< ChBodyGetBrakeBody (VehicleSide side) const
 Specify the body on the specified side for a possible connection to brake subsystem. More...
 
void ApplyParkingBrake (bool brake)
 Simple model of a parking brake.
 
- 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.
 
virtual void SetOutput (bool state)
 Enable/disable output for this subsystem.
 
bool OutputEnabled () const
 Return the output state for this subsystem.
 

Protected Types

enum  PointId {
  SPINDLE, UPRIGHT, UCA_F, UCA_B,
  UCA_U, UCA_CM, LCA_F, LCA_B,
  LCA_U, LCA_CM, SHOCK_C, SHOCK_A,
  SPRING_C, SPRING_A, TIEROD_C, TIEROD_U,
  NUM_POINTS
}
 Identifiers for the various hardpoints. More...
 

Protected Member Functions

 ChDoubleWishbone (const std::string &name, bool vehicle_frame_inertia=false)
 Protected constructor. More...
 
void SetVehicleFrameInertiaFlag (bool val)
 Indicate whether or not inertia matrices are specified with respect to a vehicle-aligned centroidal frame (flag=true) or with respect to the body centroidal frame (flag=false). More...
 
virtual const ChVector getLocation (PointId which)=0
 Return the location of the specified hardpoint. More...
 
virtual double getSpindleMass () const =0
 Return the mass of the spindle body.
 
virtual double getUCAMass () const =0
 Return the mass of the upper control arm body.
 
virtual double getLCAMass () const =0
 Return the mass of the lower control body.
 
virtual double getUprightMass () const =0
 Return the mass of the upright body.
 
virtual const ChVectorgetSpindleInertia () const =0
 Return the moments of inertia of the spindle body.
 
virtual const ChVectorgetUCAInertiaMoments () const =0
 Return the moments of inertia of the upper control arm body.
 
virtual const ChVectorgetUCAInertiaProducts () const =0
 Return the products of inertia of the upper control arm body.
 
virtual const ChVectorgetLCAInertiaMoments () const =0
 Return the moments of inertia of the lower control arm body.
 
virtual const ChVectorgetLCAInertiaProducts () const =0
 Return the products of inertia of the lower control arm body.
 
virtual const ChVectorgetUprightInertiaMoments () const =0
 Return the moments of inertia of the upright body.
 
virtual const ChVectorgetUprightInertiaProducts () const =0
 Return the products of inertia of the upright body.
 
virtual double getAxleInertia () const =0
 Return the inertia of the axle shaft.
 
virtual double getUCARadius () const =0
 Return the radius of the upper control arm body (visualization only).
 
virtual double getLCARadius () const =0
 Return the radius of the lower control arm body (visualization only).
 
virtual double getUprightRadius () const =0
 Return the radius of the upright body (visualization only).
 
virtual double getSpringRestLength () const =0
 Return the free (rest) length of the spring element.
 
virtual std::shared_ptr< ChLinkTSDA::ForceFunctorgetSpringForceFunctor () const =0
 Return the functor object for spring force.
 
virtual std::shared_ptr< ChLinkTSDA::ForceFunctorgetShockForceFunctor () const =0
 Return the functor object for shock force.
 
- 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

std::shared_ptr< ChBodym_upright [2]
 handles to the upright bodies (left/right)
 
std::shared_ptr< ChBodym_UCA [2]
 handles to the upper control arm bodies (left/right)
 
std::shared_ptr< ChBodym_LCA [2]
 handles to the lower control arm bodies (left/right)
 
std::shared_ptr< ChLinkLockRevolutem_revoluteUCA [2]
 handles to the chassis-UCA revolute joints (left/right)
 
std::shared_ptr< ChLinkLockSphericalm_sphericalUCA [2]
 handles to the upright-UCA spherical joints (left/right)
 
std::shared_ptr< ChLinkLockRevolutem_revoluteLCA [2]
 handles to the chassis-LCA revolute joints (left/right)
 
std::shared_ptr< ChLinkLockSphericalm_sphericalLCA [2]
 handles to the upright-LCA spherical joints (left/right)
 
std::shared_ptr< ChLinkDistancem_distTierod [2]
 handles to the tierod distance constraints (left/right)
 
std::shared_ptr< ChLinkTSDAm_shock [2]
 handles to the spring links (left/right)
 
std::shared_ptr< ChLinkTSDAm_spring [2]
 handles to the shock links (left/right)
 
- Protected Attributes inherited from chrono::vehicle::ChSuspension
ChVector m_location
 location relative to chassis
 
std::shared_ptr< ChBodym_spindle [2]
 handles to spindle bodies
 
std::shared_ptr< ChShaftm_axle [2]
 handles to axle shafts
 
std::shared_ptr< ChShaftsBodym_axle_to_spindle [2]
 handles to spindle-shaft connectors
 
std::shared_ptr< ChLinkLockRevolutem_revolute [2]
 handles to spindle revolute joints
 
- 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
 

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< 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 Enumeration Documentation

◆ PointId

Identifiers for the various hardpoints.

Enumerator
SPINDLE 

spindle location

UPRIGHT 

upright location

UCA_F 

upper control arm, chassis front

UCA_B 

upper control arm, chassis back

UCA_U 

upper control arm, upright

UCA_CM 

upper control arm, center of mass

LCA_F 

lower control arm, chassis front

LCA_B 

lower control arm, chassis back

LCA_U 

lower control arm, upright

LCA_CM 

lower control arm, center of mass

SHOCK_C 

shock, chassis

SHOCK_A 

shock, lower control arm

SPRING_C 

spring, chassis

SPRING_A 

spring, lower control arm

TIEROD_C 

tierod, chassis

TIEROD_U 

tierod, upright

Constructor & Destructor Documentation

◆ ChDoubleWishbone()

chrono::vehicle::ChDoubleWishbone::ChDoubleWishbone ( const std::string &  name,
bool  vehicle_frame_inertia = false 
)
protected

Protected constructor.

Parameters
[in]namename of the subsystem
[in]vehicle_frame_inertiainertia specified in vehicle-aligned centroidal frames?

Member Function Documentation

◆ AddVisualizationAssets()

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

Add visualization assets for the suspension subsystem.

This default implementation uses primitives.

Reimplemented from chrono::vehicle::ChSuspension.

◆ GetAntirollBody()

virtual std::shared_ptr<ChBody> chrono::vehicle::ChDoubleWishbone::GetAntirollBody ( VehicleSide  side) const
inlineoverridevirtual

Specify the suspension body on the specified side to attach a possible antirollbar subsystem.

Return the corresponding lower control arm.

Reimplemented from chrono::vehicle::ChSuspension.

◆ getLocation()

virtual const ChVector chrono::vehicle::ChDoubleWishbone::getLocation ( PointId  which)
protectedpure virtual

Return the location of the specified hardpoint.

The returned location must be expressed in the suspension reference frame.

Implemented in chrono::vehicle::generic::Generic_DoubleWishboneRear, chrono::vehicle::generic::Generic_DoubleWishboneFront, chrono::vehicle::generic::Generic_DoubleWishbone, and chrono::vehicle::sedan::Sedan_DoubleWishbone.

◆ Initialize()

void chrono::vehicle::ChDoubleWishbone::Initialize ( std::shared_ptr< ChChassis chassis,
std::shared_ptr< ChSubchassis subchassis,
std::shared_ptr< ChSteering steering,
const ChVector<> &  location,
double  left_ang_vel = 0,
double  right_ang_vel = 0 
)
overridevirtual

Initialize this suspension subsystem.

The suspension subsystem is initialized by attaching it to the specified chassis and (if provided) to the specified subchassis, at the specified location (with respect to and expressed in the reference frame of the chassis). It is assumed that the suspension reference frame is always aligned with the chassis reference frame. If a steering subsystem is provided, the suspension tierods are to be attached to the steering's central link body (steered suspension); otherwise they are to be attached to the chassis (non-steered suspension).

Parameters
[in]chassisassociated chassis subsystem
[in]subchassisassociated subchassis subsystem (may be null)
[in]steeringassociated steering subsystem (may be null)
[in]locationlocation relative to the chassis frame
[in]left_ang_velinitial angular velocity of left wheel
[in]right_ang_velinitial angular velocity of right wheel

Implements chrono::vehicle::ChSuspension.

◆ LogHardpointLocations()

void chrono::vehicle::ChDoubleWishbone::LogHardpointLocations ( const ChVector<> &  ref,
bool  inches = false 
)

Log the locations of all hardpoints.

The reported locations are expressed in the suspension reference frame. By default, these values are reported in SI units (meters), but can be optionally reported in inches.

◆ SetVehicleFrameInertiaFlag()

void chrono::vehicle::ChDoubleWishbone::SetVehicleFrameInertiaFlag ( bool  val)
inlineprotected

Indicate whether or not inertia matrices are specified with respect to a vehicle-aligned centroidal frame (flag=true) or with respect to the body centroidal frame (flag=false).

Note that this function must be called before Initialize().


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