1 package org.opentrafficsim.road.gtu.lane.perception.categories.neighbors;
2
3 import org.djunits.value.vdouble.scalar.Acceleration;
4 import org.djunits.value.vdouble.scalar.Length;
5 import org.djunits.value.vdouble.scalar.Speed;
6 import org.djunits.value.vdouble.scalar.Time;
7 import org.opentrafficsim.base.parameters.ParameterException;
8 import org.opentrafficsim.road.gtu.lane.LaneBasedGTU;
9 import org.opentrafficsim.road.gtu.lane.perception.mental.AdaptationSituationalAwareness;
10
11 /**
12 * Estimation of neighbor headway, speed and acceleration.
13 * <p>
14 * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
15 * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
16 * <p>
17 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 6 apr. 2018 <br>
18 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
19 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
20 * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
21 */
22 public interface Estimation
23 {
24 /** No estimation errors. */
25 Estimation NONE = new Estimation()
26 {
27 @Override
28 public NeighborTriplet estimate(final LaneBasedGTU perceivingGtu, final LaneBasedGTU perceivedGtu,
29 final Length distance, final boolean downstream, final Time when) throws ParameterException
30 {
31 return new NeighborTriplet(distance, perceivedGtu.getSpeed(), perceivedGtu.getAcceleration());
32 }
33 };
34
35 /** Underestimation based on situational awareness. */
36 Estimation UNDERESTIMATION = new FactorEstimation()
37 {
38 /** {@inheritDoc} */
39 @Override
40 boolean overEstimation()
41 {
42 return false;
43 }
44 };
45
46 /** OVerestimation based on situational awareness. */
47 Estimation OVERESTIMATION = new FactorEstimation()
48 {
49 /** {@inheritDoc} */
50 @Override
51 boolean overEstimation()
52 {
53 return true;
54 }
55 };
56
57 /**
58 * Estimate headway, speed and acceleration.
59 * @param perceivingGtu LaneBasedGTU; perceiving GTU
60 * @param perceivedGtu LaneBasedGTU; perceived GTU
61 * @param distance Length; actual headway at 'now' (i.e. not at 'when' if there is a reaction time)
62 * @param downstream boolean; downstream (or upstream) neighbor
63 * @param when Time; moment of perception, reaction time included
64 * @return NeighborTriplet; perceived headway, speed and acceleration
65 * @throws ParameterException on invalid parameter value or if parameter is not available
66 */
67 NeighborTriplet estimate(LaneBasedGTU perceivingGtu, LaneBasedGTU perceivedGtu, Length distance, boolean downstream,
68 Time when) throws ParameterException;
69
70 /**
71 * Estimation based on a factor.
72 * <p>
73 * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
74 * <br>
75 * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
76 * <p>
77 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 31 jan. 2019 <br>
78 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
79 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
80 * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
81 */
82 abstract class FactorEstimation implements Estimation
83 {
84
85 /** Sign. */
86 private final double sign;
87
88 /**
89 * Constructor.
90 */
91 FactorEstimation()
92 {
93 this.sign = overEstimation() ? 1.0 : -1.0;
94 }
95
96 /** {@inheritDoc} */
97 @Override
98 public NeighborTriplet estimate(final LaneBasedGTU perceivingGtu, final LaneBasedGTU perceivedGtu,
99 final Length distance, final boolean downstream, final Time when) throws ParameterException
100 {
101 double factor = 1.0 + this.sign * (perceivingGtu.getParameters().getParameter(AdaptationSituationalAwareness.SA_MAX)
102 - perceivingGtu.getParameters().getParameter(AdaptationSituationalAwareness.SA));
103 double delta = (perceivedGtu.getOdometer().si - perceivedGtu.getOdometer(when).si)
104 - (perceivingGtu.getOdometer().si - perceivingGtu.getOdometer(when).si);
105 if (downstream)
106 {
107 delta = -delta; // faster leader increases the headway, faster follower reduces the headway
108 }
109 Length headway = Length.createSI((distance.si + delta) * factor);
110 double egoSpeed = perceivingGtu.getSpeed(when).si;
111 Speed speed = Speed.createSI(egoSpeed + factor * (perceivedGtu.getSpeed(when).si - egoSpeed));
112 Acceleration acceleration = perceivedGtu.getAcceleration(when);
113 return new NeighborTriplet(headway, speed, acceleration);
114 }
115
116 /**
117 * Returns whether this is over-estimation.
118 * @return boolean; whether this is over-estimation
119 */
120 abstract boolean overEstimation();
121 }
122
123 }