SUMO - Simulation of Urban MObility
MSCFModel_IDM Class Reference

The Intelligent Driver Model (IDM) car-following model. More...

#include <MSCFModel_IDM.h>

Inheritance diagram for MSCFModel_IDM:
MSCFModel

Data Structures

class  VehicleVariables

Public Member Functions

VehicleVariablescreateVehicleVariables () const
 Returns model specific values which are stored inside a vehicle and must be used with casting.
MSCFModelduplicate (const MSVehicleType *vtype) const
 Duplicates the car-following model.
 MSCFModel_IDM (const MSVehicleType *vtype, SUMOReal accel, SUMOReal decel, SUMOReal headwayTime, SUMOReal delta, SUMOReal internalStepping)
 Constructor.
 MSCFModel_IDM (const MSVehicleType *vtype, SUMOReal accel, SUMOReal decel, SUMOReal headwayTime, SUMOReal adaptationFactor, SUMOReal adaptationTime, SUMOReal internalStepping)
 Constructor.
 ~MSCFModel_IDM ()
 Destructor.
Implementations of the MSCFModel interface
SUMOReal moveHelper (MSVehicle *const veh, SUMOReal vPos) const
 Applies interaction with stops and lane changing model influences.
SUMOReal followSpeed (const MSVehicle *const veh, SUMOReal speed, SUMOReal gap2pred, SUMOReal predSpeed, SUMOReal predMaxDecel) const
 Computes the vehicle's safe speed (no dawdling)
SUMOReal stopSpeed (const MSVehicle *const veh, SUMOReal gap2pred) const
 Computes the vehicle's safe speed for approaching a non-moving obstacle (no dawdling)
SUMOReal interactionGap (const MSVehicle *const , SUMOReal vL) const
 Returns the maximum gap at which an interaction between both vehicles occurs.
int getModelID () const
 Returns the model's name.
Methods to override by model implementation
virtual SUMOReal freeSpeed (const MSVehicle *const veh, SUMOReal speed, SUMOReal seen, SUMOReal maxSpeed) const
 Computes the vehicle's safe speed without a leader.
virtual void saveState (std::ostream &os)
 Saves the model's definition into the state.
Virtual methods with default implementation
virtual SUMOReal getMaxAccel () const
 Get the vehicle type's maximum acceleration [m/s^2].
virtual SUMOReal getMaxDecel () const
 Get the vehicle type's maximum deceleration [m/s^2].
virtual SUMOReal getImperfection () const
 Get the driver's imperfection.
virtual SUMOReal getHeadwayTime () const
 Get the driver's reaction time [s].
Currently fixed methods
void leftVehicleVsafe (const MSVehicle *const ego, const MSVehicle *const neigh, SUMOReal &vSafe) const
 Incorporates the influence of the vehicle on the left lane.
SUMOReal maxNextSpeed (SUMOReal speed) const
 Returns the maximum speed given the current speed.
SUMOReal brakeGap (SUMOReal speed) const
 Returns the distance the vehicle needs to halt including driver's reaction time.
SUMOReal getSecureGap (const SUMOReal speed, const SUMOReal leaderSpeed, const SUMOReal leaderMaxDecel) const
 Returns the minimum gap to reserve if the leader is braking at maximum.
SUMOReal getSpeedAfterMaxDecel (SUMOReal v) const
 Returns the velocity after maximum deceleration.
Setter methods
virtual void setMaxAccel (SUMOReal accel)
 Sets a new value for maximum acceleration [m/s^2].
virtual void setMaxDecel (SUMOReal decel)
 Sets a new value for maximum deceleration [m/s^2].
virtual void setImperfection (SUMOReal imperfection)
 Sets a new value for driver imperfection.
virtual void setHeadwayTime (SUMOReal headwayTime)
 Sets a new value for driver reaction time [s].

Protected Attributes

SUMOReal myAccel
 The vehicle's maximum acceleration [m/s^2].
SUMOReal myDecel
 The vehicle's maximum deceleration [m/s^2].
SUMOReal myHeadwayTime
 The driver's desired time headway (aka reaction time tau) [s].
const MSVehicleTypemyType
 The type to which this model definition belongs to.

Private Member Functions

SUMOReal _v (const MSVehicle *const veh, SUMOReal gap2pred, SUMOReal mySpeed, SUMOReal predSpeed, SUMOReal desSpeed) const
SUMOReal desiredSpeed (const MSVehicle *const veh) const

Private Attributes

const SUMOReal myAdaptationFactor
 The IDMM adaptation factor beta.
const SUMOReal myAdaptationTime
 The IDMM adaptation time tau.
const SUMOReal myDelta
 The IDM delta exponent.
const SUMOReal myExpFactor
 A computational shortcut for IDMM.
const int myIterations
 The number of iterations in speed calculations.
const SUMOReal myTwoSqrtAccelDecel
 A computational shortcut.

Detailed Description

The Intelligent Driver Model (IDM) car-following model.

See also:
MSCFModel

Definition at line 48 of file MSCFModel_IDM.h.


Constructor & Destructor Documentation

MSCFModel_IDM::MSCFModel_IDM ( const MSVehicleType vtype,
SUMOReal  accel,
SUMOReal  decel,
SUMOReal  headwayTime,
SUMOReal  delta,
SUMOReal  internalStepping 
)

Constructor.

Parameters:
[in]accelThe maximum acceleration
[in]decelThe maximum deceleration
[in]headwayTimethe headway gap
[in]deltaa model constant
[in]internalSteppinginternal time step size

Definition at line 43 of file MSCFModel_IDM.cpp.

Referenced by duplicate().

MSCFModel_IDM::MSCFModel_IDM ( const MSVehicleType vtype,
SUMOReal  accel,
SUMOReal  decel,
SUMOReal  headwayTime,
SUMOReal  adaptationFactor,
SUMOReal  adaptationTime,
SUMOReal  internalStepping 
)

Constructor.

Parameters:
[in]accelThe maximum acceleration
[in]decelThe maximum deceleration
[in]headwayTimethe headway gap
[in]adaptationFactora model constant
[in]adaptationTimea model constant
[in]internalSteppinginternal time step size

Definition at line 53 of file MSCFModel_IDM.cpp.

Destructor.

Definition at line 63 of file MSCFModel_IDM.cpp.


Member Function Documentation

SUMOReal MSCFModel::brakeGap ( SUMOReal  speed) const [inherited]

Returns model specific values which are stored inside a vehicle and must be used with casting.

Reimplemented from MSCFModel.

Definition at line 140 of file MSCFModel_IDM.h.

References myExpFactor.

MSCFModel * MSCFModel_IDM::duplicate ( const MSVehicleType vtype) const [virtual]

Duplicates the car-following model.

Parameters:
[in]vtypeThe vehicle type this model belongs to (1:1)
Returns:
A duplicate of this car-following model

Implements MSCFModel.

Definition at line 127 of file MSCFModel_IDM.cpp.

References MSCFModel_IDM(), MSCFModel::myAccel, MSCFModel::myDecel, myDelta, MSCFModel::myHeadwayTime, myIterations, and TS.

SUMOReal MSCFModel_IDM::followSpeed ( const MSVehicle *const  veh,
SUMOReal  speed,
SUMOReal  gap2pred,
SUMOReal  predSpeed,
SUMOReal  predMaxDecel 
) const [virtual]

Computes the vehicle's safe speed (no dawdling)

Parameters:
[in]vehThe vehicle (EGO)
[in]speedThe vehicle's speed
[in]gap2predThe (netto) distance to the LEADER
[in]predSpeedThe speed of LEADER
Returns:
EGO's safe speed
See also:
MSCFModel::ffeV

Implements MSCFModel.

Definition at line 79 of file MSCFModel_IDM.cpp.

References _v(), and desiredSpeed().

virtual SUMOReal MSCFModel::freeSpeed ( const MSVehicle *const  veh,
SUMOReal  speed,
SUMOReal  seen,
SUMOReal  maxSpeed 
) const [inline, virtual, inherited]

Computes the vehicle's safe speed without a leader.

Returns the velocity of the vehicle in dependence to the length of the free street and the target velocity at the end of the free range.

Parameters:
[in]vehThe vehicle (EGO)
[in]speedThe vehicle's speed
[in]seenThe look ahead distance
[in]maxSpeedThe maximum allowed speed
Returns:
EGO's safe speed

Definition at line 96 of file MSCFModel.h.

References MSCFModel::followSpeed().

Referenced by getMaxSpeedRegardingNextLanes(), MSLane::isInsertionSuccess(), MSVehicle::moveRegardingCritical(), and MSVehicle::vsafeCriticalCont().

virtual SUMOReal MSCFModel::getHeadwayTime ( ) const [inline, virtual, inherited]

Get the driver's reaction time [s].

Returns:
The reaction time of this class' drivers in s

Definition at line 193 of file MSCFModel.h.

References MSCFModel::myHeadwayTime.

Referenced by MSVehicle::checkRewindLinkLanes(), TraCIServerAPI_VehicleType::getVariable(), MSLane::maxSpeedGapInsertion(), MSVehicle::moveChecked(), MSLane::pWagSimpleInsertion(), and MSVehicle::vsafeCriticalCont().

virtual SUMOReal MSCFModel::getImperfection ( ) const [inline, virtual, inherited]

Get the driver's imperfection.

Returns:
The imperfection of drivers of this class

Reimplemented in MSCFModel_KraussOrig1, and MSCFModel_PWag2009.

Definition at line 185 of file MSCFModel.h.

Referenced by TraCIServerAPI_VehicleType::getVariable().

virtual SUMOReal MSCFModel::getMaxAccel ( ) const [inline, virtual, inherited]

Get the vehicle type's maximum acceleration [m/s^2].

Returns:
The maximum acceleration (in m/s^2) of vehicles of this class

Definition at line 169 of file MSCFModel.h.

References MSCFModel::myAccel.

Referenced by TraCIServerAPI_VehicleType::getVariable(), MSCFModel::maxNextSpeed(), MSVehicle::vsafeCriticalCont(), and MSMeanData_HBEFA::MSLaneMeanDataValues::write().

int MSCFModel_IDM::getModelID ( ) const [inline, virtual]

Returns the model's name.

Returns:
The model's name
See also:
MSCFModel::getModelName

Implements MSCFModel.

Definition at line 126 of file MSCFModel_IDM.h.

References myExpFactor, SUMO_TAG_CF_IDM, and SUMO_TAG_CF_IDMM.

SUMOReal MSCFModel::getSecureGap ( const SUMOReal  speed,
const SUMOReal  leaderSpeed,
const SUMOReal  leaderMaxDecel 
) const [inline, inherited]

Returns the minimum gap to reserve if the leader is braking at maximum.

Parameters:
[in]speedEGO's speed
[in]leaderSpeedLEADER's speed
[in]leaderMaxDecelLEADER's max. deceleration rate

Definition at line 239 of file MSCFModel.h.

References ACCEL2SPEED, MSCFModel::brakeGap(), MAX2(), SPEED2DIST, and SUMOReal.

Referenced by MSLaneChanger::change2left(), MSLaneChanger::change2right(), MSLane::freeInsertion(), MSLCM_DK2004::informBlocker(), and MSLane::isInsertionSuccess().

SUMOReal MSCFModel::getSpeedAfterMaxDecel ( SUMOReal  v) const [inline, inherited]

Returns the velocity after maximum deceleration.

Parameters:
[in]vThe velocity
Returns:
The velocity after maximum deceleration

Definition at line 250 of file MSCFModel.h.

References ACCEL2SPEED, MAX2(), MSCFModel::myDecel, and SUMOReal.

Referenced by MSCFModel_Krauss::followSpeed(), MSVehicle::moveRegardingCritical(), MSCFModel_Krauss::stopSpeed(), MSCFModel_Wiedemann::stopSpeed(), and MSVehicle::vsafeCriticalCont().

SUMOReal MSCFModel_IDM::interactionGap ( const MSVehicle * const  veh,
SUMOReal  vL 
) const [virtual]

Returns the maximum gap at which an interaction between both vehicles occurs.

"interaction" means that the LEADER influences EGO's speed.

Parameters:
[in]vehThe EGO vehicle
[in]vLLEADER's speed
Returns:
The interaction gap
Todo:
evaluate signature
See also:
MSCFModel::interactionGap
Todo:
update interactionGap logic to IDM

Reimplemented from MSCFModel.

Definition at line 95 of file MSCFModel_IDM.cpp.

References desiredSpeed(), MSVehicle::getSpeed(), MAX2(), MSCFModel::myAccel, MSCFModel::myDecel, myDelta, SPEED2DIST, and SUMOReal.

void MSCFModel::leftVehicleVsafe ( const MSVehicle *const  ego,
const MSVehicle *const  neigh,
SUMOReal vSafe 
) const [inherited]

Incorporates the influence of the vehicle on the left lane.

In Germany, vehicles on the right lane must not pass a vehicle on the lane left to the if the allowed velocity>60km/h

Parameters:
[in]egoThe ego vehicle
[in]neighThe neighbor vehicle on the left lane
[in,out]vSafeCurrent vSafe; may be adapted due to the left neighbor

Definition at line 86 of file MSCFModel.cpp.

References MSCFModel::followSpeed(), MSVehicle::getCarFollowModel(), MSVehicleType::getLength(), MSCFModel::getMaxDecel(), MSVehicleType::getMinGap(), MSVehicle::getPositionOnLane(), MSVehicle::getSpeed(), MSBaseVehicle::getVehicleType(), MAX2(), MIN2(), and SUMOReal.

Referenced by MSVehicle::moveRegardingCritical().

SUMOReal MSCFModel::maxNextSpeed ( SUMOReal  speed) const [inherited]

Returns the maximum speed given the current speed.

The implementation of this method must take into account the time step duration.

Justification: Due to air brake or other influences, the vehicle's next maximum speed may depend on the vehicle's current speed (given).

Parameters:
[in]speedThe vehicle's current speed
Returns:
The maximum possible speed for the next step

Definition at line 98 of file MSCFModel.cpp.

References ACCEL2SPEED, MSCFModel::getMaxAccel(), MSVehicleType::getMaxSpeed(), MIN2(), MSCFModel::myType, and SUMOReal.

Referenced by MSCFModel_Kerner::followSpeed(), MSCFModel_Krauss::followSpeed(), MSCFModel_KraussOrig1::followSpeed(), MSLane::getFollowerOnConsecutive(), MSCFModel::interactionGap(), MSVehicle::moveChecked(), MSCFModel_KraussOrig1::moveHelper(), MSCFModel::moveHelper(), MSVehicle::moveRegardingCritical(), MSLCM_DK2004::patchSpeed(), MSCFModel_Kerner::stopSpeed(), MSCFModel_Krauss::stopSpeed(), MSCFModel_KraussOrig1::stopSpeed(), MSCFModel_Wiedemann::stopSpeed(), and MSVehicle::vsafeCriticalCont().

SUMOReal MSCFModel_IDM::moveHelper ( MSVehicle *const  veh,
SUMOReal  vPos 
) const [virtual]

Applies interaction with stops and lane changing model influences.

Parameters:
[in]vehThe ego vehicle
[in]vPosThe possible velocity
Returns:
The velocity after applying interactions with stops and lane change model influences

Reimplemented from MSCFModel.

Definition at line 67 of file MSCFModel_IDM.cpp.

References desiredSpeed(), MSVehicle::getCarFollowVariables(), MSCFModel_IDM::VehicleVariables::levelOfService, myAdaptationTime, myExpFactor, and SUMOReal.

void MSCFModel::saveState ( std::ostream &  os) [virtual, inherited]

Saves the model's definition into the state.

Parameters:
[in]osThe output to write the definition into

Definition at line 113 of file MSCFModel.cpp.

virtual void MSCFModel::setHeadwayTime ( SUMOReal  headwayTime) [inline, virtual, inherited]

Sets a new value for driver reaction time [s].

Parameters:
[in]headwayTimeThe new driver reaction time (in s)

Reimplemented in MSCFModel_KraussOrig1.

Definition at line 286 of file MSCFModel.h.

References MSCFModel::myHeadwayTime.

Referenced by TraCIServerAPI_VehicleType::setVariable().

virtual void MSCFModel::setImperfection ( SUMOReal  imperfection) [inline, virtual, inherited]

Sets a new value for driver imperfection.

Parameters:
[in]accelThe new driver imperfection

Reimplemented in MSCFModel_KraussOrig1.

Definition at line 278 of file MSCFModel.h.

References UNUSED_PARAMETER.

Referenced by TraCIServerAPI_VehicleType::setVariable().

virtual void MSCFModel::setMaxAccel ( SUMOReal  accel) [inline, virtual, inherited]

Sets a new value for maximum acceleration [m/s^2].

Parameters:
[in]accelThe new acceleration in m/s^2

Definition at line 262 of file MSCFModel.h.

References MSCFModel::myAccel.

Referenced by TraCIServerAPI_VehicleType::setVariable().

virtual void MSCFModel::setMaxDecel ( SUMOReal  decel) [inline, virtual, inherited]

Sets a new value for maximum deceleration [m/s^2].

Parameters:
[in]accelThe new deceleration in m/s^2

Reimplemented in MSCFModel_KraussOrig1.

Definition at line 270 of file MSCFModel.h.

References MSCFModel::myDecel.

Referenced by TraCIServerAPI_VehicleType::setVariable().

SUMOReal MSCFModel_IDM::stopSpeed ( const MSVehicle *const  veh,
SUMOReal  gap2pred 
) const [virtual]

Computes the vehicle's safe speed for approaching a non-moving obstacle (no dawdling)

Parameters:
[in]vehThe vehicle (EGO)
[in]gap2predThe (netto) distance to the the obstacle
Returns:
EGO's safe speed for approaching a non-moving obstacle
See also:
MSCFModel::ffeS
Todo:
generic Interface, models can call for the values they need

Implements MSCFModel.

Definition at line 85 of file MSCFModel_IDM.cpp.

References _v(), desiredSpeed(), and MSVehicle::getSpeed().


Field Documentation

The IDMM adaptation factor beta.

Definition at line 170 of file MSCFModel_IDM.h.

Referenced by _v().

The IDMM adaptation time tau.

Definition at line 173 of file MSCFModel_IDM.h.

Referenced by moveHelper().

The IDM delta exponent.

Definition at line 167 of file MSCFModel_IDM.h.

Referenced by _v(), duplicate(), and interactionGap().

A computational shortcut for IDMM.

Definition at line 176 of file MSCFModel_IDM.h.

Referenced by _v(), createVehicleVariables(), getModelID(), and moveHelper().

The number of iterations in speed calculations.

Definition at line 179 of file MSCFModel_IDM.h.

Referenced by _v(), and duplicate().

A computational shortcut.

Definition at line 182 of file MSCFModel_IDM.h.

Referenced by _v().

const MSVehicleType* MSCFModel::myType [protected, inherited]

The type to which this model definition belongs to.

Definition at line 294 of file MSCFModel.h.

Referenced by MSCFModel_Wiedemann::_v(), _v(), desiredSpeed(), and MSCFModel::maxNextSpeed().


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