-
Notifications
You must be signed in to change notification settings - Fork 2
/
MH370BackTrack.py
executable file
·134 lines (105 loc) · 6.4 KB
/
MH370BackTrack.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
#!/usr/bin/env python
# http://mcleodsean.wordpress.com/2014/04/15/mh-370-back-tracking/
import math
import matplotlib.pyplot as plt
from matplotlib.patches import Circle
satelliteInfo0011 = { 'Y': 0.0, 'Vz': 159.58, 'LOSSpeed': 250.43, 'PreviousPingTimeOffset': 91.0, 'PingRadius': 2652, 'Color': 'b', 'Elevation': 39.33 }
satelliteInfo2240 = { 'Y': 233.91 - 451.20, 'Vz': 123.31, 'LOSSpeed': 175.49, 'PreviousPingTimeOffset': 60.0, 'PingRadius': 2206, 'Color': 'r', 'Elevation': 47.54 }
satelliteInfo2140 = { 'Y': 233.91 - 557.62, 'Vz': 88.38, 'LOSSpeed': 118.34, 'PreviousPingTimeOffset': 60.0, 'PingRadius': 1965, 'Color': 'g', 'Elevation': 52.01 }
satelliteInfo2040 = { 'Y': 233.91 - 625.88, 'Vz': 47.42, 'LOSSpeed': 57.02, 'PreviousPingTimeOffset': 60.0, 'PingRadius': 1806, 'Color': 'c', 'Elevation': 54.98 }
satelliteInfo1940 = { 'Y': 233.91 - 651.30, 'Vz': 3.22, 'LOSSpeed': 4.97, 'PreviousPingTimeOffset': 78.0, 'PingRadius': 1760, 'Color': 'm', 'Elevation': 55.80 }
satelliteInfos = [satelliteInfo0011, satelliteInfo2240, satelliteInfo2140, satelliteInfo2040, satelliteInfo1940]
LOSSpeeds = [ (250.43, 125.35), (175.49, 100.64), (118.34, 79.85), (57.02, 65.80), (4.97, 39.14) ]
aircraftGS = 470
# Setup LOS Speeds
LOSSpeedsSelection = 1
for index in range(0, len(satelliteInfos)):
first, second = LOSSpeeds[index]
if LOSSpeedsSelection == 1:
satelliteInfos[index]['LOSSpeed'] = first
else:
satelliteInfos[index]['LOSSpeed'] = second
# Set up plot
fig = plt.figure(1, figsize=(8.5, 11))
ax = plt.subplot(111, aspect='equal')
#ax.set_xlim(-3000,3000)
#ax.set_ylim(3000,-3000)
graph_limits = ((-4000,5000), (-3000,3000))
ax.set_xlim(*graph_limits[0])
ax.set_ylim(*reversed(graph_limits[1]))
for satelliteInfo in satelliteInfos:
pingCircle = Circle((0,satelliteInfo['Y']), radius=satelliteInfo['PingRadius'], fill=False)
ax.add_artist(pingCircle)
ax.scatter(0, satelliteInfo['Y'], c=satelliteInfo['Color'])
ax.set_title("MH370 Backtrack - %dkt - Last Doppler LOS Speed - %dkt" % (aircraftGS, satelliteInfos[0]['LOSSpeed']))
ax.text(0, 2800, '00:11')
ax.text(0, 2150, '22:40')
ax.text(0, 1800, '21:40')
ax.text(0, 1550, '20:40')
ax.text(0, 1300, '19:40')
# Last radar position lat - 6.5381 lon - 96.408
ax.scatter(1906.59, -354.75, c='y', s=50, marker='D')
aircraftCircle = Circle((1906.59,-354.75), radius=650, fill=False, color='y')
ax.add_artist(aircraftCircle)
ax.annotate('Northern 19:40 Arc', xy=(1668,-958), xytext=(700,-1100), arrowprops=dict(facecolor='black'))
ax.annotate('Southern 19:40 Arc', xy=(1634,235), xytext=(600,100), arrowprops=dict(facecolor='black'))
latitudes = [(35, ' '), (333, 'S5'), (632, 'S10'), (931, 'S15'), (1223, 'S20'), (1528, 'S25'), (1828, 'S30'), (2127, 'S35'), (-263, 'N5'), (-562, 'N10'), (-861, 'N15')]
for latitude in latitudes:
yCart, latText = latitude
ax.plot((graph_limits[0][0],graph_limits[0][1]-350), (yCart,yCart), color='grey', alpha=0.5)
ax.text(graph_limits[0][1]-300, yCart, latText)
def distance(x1, y1, x2, y2):
dx = x1 - x2
dy = y1 - y2
return math.sqrt(dx * dx + dy * dy)
def calc(aircraftX, aircraftY, satelliteIndex):
if satelliteIndex == len(satelliteInfos) - 1:
return
# Unpack satellite info
satelliteInfo = satelliteInfos[satelliteIndex]
satelliteVz = satelliteInfo['Vz']
satelliteElevation = satelliteInfo['Elevation']
satelliteY = satelliteInfo['Y']
LOSSpeed = satelliteInfo['LOSSpeed']
backtrackTime = satelliteInfo['PreviousPingTimeOffset']
distanceFromSatelliteToAircraft = distance(0.0, satelliteY, aircraftX, aircraftY)
bearingFromSatelliteToAircaft = math.asin(aircraftX/distanceFromSatelliteToAircraft)
aircraftDistanceCoveredBetweenLastTwoPings = (backtrackTime / 60.0) * aircraftGS
satelliteCone = satelliteVz * math.cos(math.radians(satelliteElevation))
aircraftCone = aircraftGS * math.cos(math.radians(satelliteElevation))
satelliteLOS = satelliteCone * math.cos(bearingFromSatelliteToAircaft)
try:
aircraftBearingAngleDifference = math.degrees(math.acos((LOSSpeed + satelliteLOS) / aircraftCone))
except ValueError:
return
aircraftLOS = aircraftCone * math.cos(math.radians(aircraftBearingAngleDifference))
finalLOS = aircraftLOS - satelliteLOS
bearingPositive = 180 - math.degrees(bearingFromSatelliteToAircaft) + aircraftBearingAngleDifference
bearingNegative = 180 - math.degrees(bearingFromSatelliteToAircaft) - aircraftBearingAngleDifference
matches = []
for bearing in [bearingPositive, bearingNegative]:
previousAircraftX = -9999
previousAircraftY = -9999
if bearing > 90.0 and bearing <= 180.0:
previousAircraftX = aircraftX - aircraftDistanceCoveredBetweenLastTwoPings * math.sin(math.radians(180.0 - bearing))
previousAircraftY = aircraftY - aircraftDistanceCoveredBetweenLastTwoPings * math.cos(math.radians(180.0 - bearing))
elif bearing > 180.0 and bearing <= 270.0:
previousAircraftX = aircraftX + aircraftDistanceCoveredBetweenLastTwoPings * math.sin(math.radians(bearing - 180.0))
previousAircraftY = aircraftY - aircraftDistanceCoveredBetweenLastTwoPings * math.cos(math.radians(bearing - 180.0))
if previousAircraftX != -9999 and previousAircraftY != -9999:
distanceFromPreviousSatelitePoint = distance(0.0, satelliteInfos[satelliteIndex + 1]['Y'], previousAircraftX, previousAircraftY)
rangeRingDiff = math.fabs(distanceFromPreviousSatelitePoint - satelliteInfos[satelliteIndex + 1]['PingRadius'])
if rangeRingDiff < (0.02 + (satelliteIndex * 0.5)/100.0) * satelliteInfos[satelliteIndex + 1]['PingRadius']:
if satelliteIndex == 0:
ax.scatter(aircraftX, aircraftY, c=satelliteInfo['Color'])
ax.scatter(previousAircraftX, previousAircraftY, c=satelliteInfos[satelliteIndex + 1]['Color'])
ax.plot([aircraftX, previousAircraftX], [aircraftY, previousAircraftY])
calc(previousAircraftX, previousAircraftY, satelliteIndex + 1)
return
for bearing in range(1, 360, 1):
pingRadius = satelliteInfos[0]['PingRadius']
aircraftX = pingRadius * math.sin(math.radians(bearing))
aircraftY = pingRadius * math.cos(math.radians(bearing))
calc(aircraftX, aircraftY, 0)
plt.savefig("MH370 Backtrack - %dkt - Last Doppler LOS Speed - %dkt.png" % (aircraftGS, satelliteInfos[0]['LOSSpeed']))
plt.show()