Line data    Source code

       1             : /****************************************************************************/
       2             : // Eclipse SUMO, Simulation of Urban MObility; see https://eclipse.dev/sumo
       3             : // Copyright (C) 2001-2024 German Aerospace Center (DLR) and others.
       4             : // This program and the accompanying materials are made available under the
       5             : // terms of the Eclipse Public License 2.0 which is available at
       6             : // https://www.eclipse.org/legal/epl-2.0/
       7             : // This Source Code may also be made available under the following Secondary
       8             : // Licenses when the conditions for such availability set forth in the Eclipse
       9             : // Public License 2.0 are satisfied: GNU General Public License, version 2
      10             : // or later which is available at
      11             : // https://www.gnu.org/licenses/old-licenses/gpl-2.0-standalone.html
      12             : // SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-or-later
      13             : /****************************************************************************/
      14             : /// @file    MSCFModel_Kerner.cpp
      15             : /// @author  Daniel Krajzewicz
      16             : /// @author  Laura Bieker
      17             : /// @author  Michael Behrisch
      18             : /// @date    03.04.2010
      19             : ///
      20             : // car-following model by B. Kerner
      21             : // Implementation based on "B. S. Kerner, S. L. Klenov, A. Brakemeier, Testbed for Wireless Vehicle Communication: a
      22             : // Simulation Approach based on Three-Phase Traffic Theory"
      23             : // https://arxiv.org/abs/0712.2711
      24             : /****************************************************************************/
      25             : #include <config.h>
      26             : 
      27             : #include <microsim/MSVehicle.h>
      28             : #include <microsim/MSLane.h>
      29             : #include "MSCFModel_Kerner.h"
      30             : #include <utils/common/RandHelper.h>
      31             : 
      32             : 
      33             : // ===========================================================================
      34             : // method definitions
      35             : // ===========================================================================
      36         231 : MSCFModel_Kerner::MSCFModel_Kerner(const MSVehicleType* vtype) :
      37             :     MSCFModel(vtype),
      38         231 :     myK(vtype->getParameter().getCFParam(SUMO_ATTR_K, 0.5)),
      39         231 :     myPhi(vtype->getParameter().getCFParam(SUMO_ATTR_CF_KERNER_PHI, 5.0)),
      40         231 :     myTauDecel(myDecel * myHeadwayTime) {
      41             :     // Kerner does not drive very precise and may violate minGap on occasion
      42         231 :     myCollisionMinGapFactor = vtype->getParameter().getCFParam(SUMO_ATTR_COLLISION_MINGAP_FACTOR, 0.1);
      43         231 : }
      44             : 
      45             : 
      46         462 : MSCFModel_Kerner::~MSCFModel_Kerner() {}
      47             : 
      48             : 
      49             : double
      50     4319768 : MSCFModel_Kerner::finalizeSpeed(MSVehicle* const veh, double vPos) const {
      51     4319768 :     const double vNext = MSCFModel::finalizeSpeed(veh, vPos);
      52             :     VehicleVariables* vars = (VehicleVariables*)veh->getCarFollowVariables();
      53     4319768 :     vars->rand = RandHelper::rand(veh->getRNG());
      54     4319768 :     return vNext;
      55             : }
      56             : 
      57             : 
      58             : double
      59    29742536 : MSCFModel_Kerner::followSpeed(const MSVehicle* const veh, double speed, double gap, double predSpeed, double /*predMaxDecel*/, const MSVehicle* const /*pred*/, const CalcReason /*usage*/) const {
      60    29742536 :     return MIN2(_v(veh, speed, maxNextSpeed(speed, veh), gap, predSpeed), maxNextSpeed(speed, veh));
      61             : }
      62             : 
      63             : 
      64             : double
      65    12329167 : MSCFModel_Kerner::stopSpeed(const MSVehicle* const veh, const double speed, double gap, double /*decel*/, const CalcReason /*usage*/) const {
      66    12329167 :     return MIN2(_v(veh, speed, maxNextSpeed(speed, veh), gap, 0), maxNextSpeed(speed, veh));
      67             : }
      68             : 
      69             : 
      70             : MSCFModel::VehicleVariables*
      71        6879 : MSCFModel_Kerner::createVehicleVariables() const {
      72        6879 :     VehicleVariables* ret = new VehicleVariables();
      73             :     /// XXX should use egoVehicle->getRNG()
      74        6879 :     ret->rand = RandHelper::rand();
      75        6879 :     return ret;
      76             : }
      77             : 
      78             : 
      79             : double
      80    42071703 : MSCFModel_Kerner::_v(const MSVehicle* const veh, double speed, double vfree, double gap, double predSpeed) const {
      81    42071703 :     if (predSpeed == 0 && gap < 0.01) {
      82             :         return 0;
      83             :     }
      84             :     // !!! in the following, the prior step is not considered!!!
      85    41996935 :     double G = MAX2((double) 0, (double)(SPEED2DIST(myK * speed) + myPhi / myAccel * speed * (speed - predSpeed)));
      86    50509433 :     double vcond = gap > G ? speed + ACCEL2SPEED(myAccel) : speed + MAX2(ACCEL2SPEED(-myDecel), MIN2(ACCEL2SPEED(myAccel), predSpeed - speed));
      87    41996935 :     double vsafe = (double)(-1. * myTauDecel + sqrt(myTauDecel * myTauDecel + (predSpeed * predSpeed) + (2. * myDecel * gap)));
      88             :     VehicleVariables* vars = (VehicleVariables*)veh->getCarFollowVariables();
      89    41996935 :     double va = MAX2((double) 0, MIN3(vfree, vsafe, vcond)) + vars->rand;
      90             :     //std::cout << SIMTIME << " veh=" << veh->getID() << " speed=" << speed << " gap=" << gap << " G=" << G << " predSpeed=" << predSpeed << " vfree=" << vfree << " vsafe=" << vsafe << " vcond=" << vcond << " rand=" << vars->rand << "\n";
      91    41996935 :     double v = MAX2((double) 0, MIN4(vfree, va, speed + ACCEL2SPEED(myAccel), vsafe));
      92             :     return v;
      93             : }
      94             : 
      95             : 
      96             : MSCFModel*
      97           0 : MSCFModel_Kerner::duplicate(const MSVehicleType* vtype) const {
      98           0 :     return new MSCFModel_Kerner(vtype);
      99             : }