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1   package org.opentrafficsim.road.gtu.lane.perception.headway;
2   
3   import org.djunits.value.vdouble.scalar.Length;
4   import org.opentrafficsim.core.gtu.GTUException;
5   import org.opentrafficsim.core.gtu.behavioralcharacteristics.BehavioralCharacteristics;
6   import org.opentrafficsim.core.network.NetworkException;
7   import org.opentrafficsim.road.gtu.lane.LaneBasedGTU;
8   import org.opentrafficsim.road.gtu.lane.tactical.following.CarFollowingModel;
9   import org.opentrafficsim.road.network.speed.SpeedLimitInfo;
10  import org.opentrafficsim.road.network.speed.SpeedLimitTypes;
11  
12  /**
13   * Container for a reference to information about a (lane based) GTU and a headway. The Headway can store information about GTUs
14   * or objects ahead of the reference GTU, behind the reference GTU, or (partially) parallel to the reference GTU. In addition to
15   * the (perceived) headway, several other pieces of information can be stored, such as (perceived) speed, (perceived)
16   * acceleration, (perceived) turn indicators, and (perceived) braking lights. <br>
17   * This particular version returns behavioral information about the observed GTU objects based on their real state.<br>
18   * Special care must be taken in curves when perceiving headway of a GTU or object on an adjacent lane.The question is whether
19   * we perceive the parallel or ahead/behind based on a line perpendicular to the front/back of the GTU (rectangular), or
20   * perpendicular to the center line of the lane (wedge-shaped in case of a curve). The difficulty of a wedge-shaped situation is
21   * that reciprocity might be violated: in case of a clothoid, for instance, it is not sure that the point on the center line
22   * when projected from lane 1 to lane 2 is the same as the projection from lane 2 to lane 1. The same holds for shapes with
23   * sharp bends. Therefore, algorithms implementing headway should only project the <i>reference point</i> of the reference GTU
24   * on the center line of the adjacent lane, and then calculate the forward position and backward position on the adjacent lane
25   * based on the reference point. Still, our human perception of what is parallel and what not, is not reflected by fractional
26   * positions. See examples in <a href=
27   * "http://simulation.tudelft.nl:8085/browse/OTS-113">http://simulation.tudelft.nl:8085/browse/OTS-113</a>.
28   * <p>
29   * Copyright (c) 2013-2016 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
30   * BSD-style license. See <a href="http://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
31   * </p>
32   * $LastChangedDate: 2015-07-24 02:58:59 +0200 (Fri, 24 Jul 2015) $, @version $Revision: 1147 $, by $Author: averbraeck $,
33   * initial version May 27, 2016 <br>
34   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
35   * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
36   * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
37   */
38  public class HeadwayGTUReal extends AbstractHeadwayGTU
39  {
40      /** */
41      private static final long serialVersionUID = 20160527L;
42  
43      /** stored car following model of the observed GTU. */
44      private final CarFollowingModel carFollowingModel;
45  
46      /** stored behavioral characteristics of the observed GTU. */
47      private final BehavioralCharacteristics behavioralCharacteristics;
48  
49      /** stored speed limit info of the observed GTU. */
50      private final SpeedLimitInfo speedLimitInfo;
51  
52      /**
53       * Construct a new Headway information object, for a GTU ahead of us or behind us.
54       * @param gtu the observed GTU, can not be null.
55       * @param distance the distance to the other object; if this constructor is used, distance cannot be null.
56       * @param gtuStatus the observable characteristics of the GTU.
57       * @throws GTUException when id is null, objectType is null, or parameters are inconsistent
58       */
59      public HeadwayGTUReal(final LaneBasedGTU gtu, final Length distance, final GTUStatus... gtuStatus) throws GTUException
60      {
61          super(gtu.getId(), gtu.getGTUType(), distance, true, gtu.getLength(), gtu.getSpeed(), gtu.getAcceleration(), gtuStatus);
62          this.carFollowingModel = gtu.getTacticalPlanner().getCarFollowingModel();
63          this.behavioralCharacteristics = new BehavioralCharacteristics(gtu.getBehavioralCharacteristics());
64          this.speedLimitInfo = getSpeedLimitInfo(gtu);
65      }
66  
67      /**
68       * Construct a new Headway information object, for a GTU parallel with us.
69       * @param gtu the observed GTU, can not be null.
70       * @param overlapFront the front-front distance to the other GTU; if this constructor is used, this value cannot be null.
71       * @param overlap the 'center' overlap with the other GTU; if this constructor is used, this value cannot be null.
72       * @param overlapRear the rear-rear distance to the other GTU; if this constructor is used, this value cannot be null.
73       * @throws GTUException when id is null, or parameters are inconsistent
74       */
75      public HeadwayGTUReal(final LaneBasedGTU gtu, final Length overlapFront, final Length overlap, final Length overlapRear)
76          throws GTUException
77      {
78          super(gtu.getId(), gtu.getGTUType(), overlapFront, overlap, overlapRear, true, gtu.getLength(), gtu.getSpeed(), gtu
79              .getAcceleration());
80          this.carFollowingModel = gtu.getTacticalPlanner().getCarFollowingModel();
81          this.behavioralCharacteristics = new BehavioralCharacteristics(gtu.getBehavioralCharacteristics());
82          this.speedLimitInfo = getSpeedLimitInfo(gtu);
83      }
84      
85      /**
86       * Creates speed limit prospect for given GTU.
87       * @param gtu gtu to the the speed limit prospect for
88       * @return speed limit prospect for given GTU
89       */
90      // TODO this is a simple fix, and getReferenceLane()
91      private SpeedLimitInfo getSpeedLimitInfo(final LaneBasedGTU gtu)
92      {
93          SpeedLimitInfo sli = new SpeedLimitInfo();
94          sli.addSpeedInfo(SpeedLimitTypes.MAX_VEHICLE_SPEED, gtu.getMaximumSpeed());
95          try
96          {
97              sli.addSpeedInfo(SpeedLimitTypes.FIXED_SIGN,
98                      gtu.getReferencePosition().getLane().getSpeedLimit(gtu.getGTUType()));
99          }
100         catch (NetworkException | GTUException exception)
101         {
102             throw new RuntimeException("Could not obtain speed limit from lane for perception.", exception);
103         }
104         return sli;
105     }
106 
107     /** {@inheritDoc} */
108     @Override
109     public final CarFollowingModel getCarFollowingModel()
110     {
111         return this.carFollowingModel;
112     }
113 
114     /** {@inheritDoc} */
115     @Override
116     public final BehavioralCharacteristics getBehavioralCharacteristics()
117     {
118         return this.behavioralCharacteristics;
119     }
120 
121     /** {@inheritDoc} */
122     @Override
123     public final SpeedLimitInfo getSpeedLimitInfo()
124     {
125         return this.speedLimitInfo;
126     }
127 
128 }