Satellites

examples/satellite.php

@@ -0,0 +1,23 @@
+<?php
+
+include __DIR__ . '/../vendor/autoload.php';
+
+use Andrmoel\AstronomyBundle\Events\SolarEclipse\SolarEclipse;
+use Andrmoel\AstronomyBundle\Location;
+use Andrmoel\AstronomyBundle\TimeOfInterest;
+
+date_default_timezone_set('UTC');
+
+$string = <<<END
+ISS             109. 73.0 27.5 -2.0 v  402
+1 25544U 98067A   19155.51091253  .00000344  00000-0  13620-4 0  9994
+2 25544  51.6453  64.2093 0007540  13.2790 173.5287 15.51165870173281
+END;
+
+$TLEParser = \Andrmoel\AstronomyBundle\Parsers\ParserFactory::get(\Andrmoel\AstronomyBundle\Parsers\TLEParser::class, $string);
+$tle = $TLEParser->getParsedData();
+
+$T = TimeOfInterest::createFromString('2019-06-04 00:00:00')->getJulianCenturiesFromJ2000();
+$kep = \Andrmoel\AstronomyBundle\Calculations\SatelliteCalc::twoLineElements2keplerianElements($tle, $T);
+
+var_dump($kep);die();

src/AstronomicalObjects/Satellite.php

@@ -0,0 +1,83 @@
+<?php
+
+namespace Andrmoel\AstronomyBundle\AstronomicalObjects;
+
+class Satellite extends AstronomicalObject
+{
+    /** @var string two line element */
+    private $tle = '';
+
+    // Satellite data
+    private $satelliteNo = 0;
+    private $classification = 0;
+    private $internationalId = 0;
+    private $revolutionNoAtEpoch = 0;
+
+    // Epoch of TLE data set
+    private $epoch = 0;
+
+    // Kepler parameters
+    private $inclination = 0;
+    private $raan = 0; // Right ascension of ascending node
+    private $eccentricity = 0;
+    private $aop = 0; // Argument of perigee
+    private $meanAnomaly = 0;
+    private $meanMotion = 0;
+
+    public function __construct($tle)
+    {
+        parent::__construct();
+
+        $this->tle = $tle;
+        $this->parseTLE();
+    }
+
+
+    /**
+     * Parse two line element
+     */
+    private function parseTLE()
+    {
+        $valid = array(
+            1 => false, // Validate line 1
+            2 => false, // Validate line 2
+        );
+
+        $lines = explode("\n", $this->tle);
+        $lines = str_replace("\r", '', $lines);
+        foreach ($lines as $line) {
+            if (strlen($line) == 69) {
+                $lineNo = substr($line, 0, 1);
+var_dump($lineNo); //TODO
+                switch ($lineNo) {
+                    case '1':
+                        $this->satelliteNo = trim(substr($line, 2, 5));
+                        $this->classification = substr($line, 7, 1);
+                        $this->internationalId = trim(substr($line, 9, 7));
+                        $this->epoch = new TimeOfInterest();
+                        $this->epoch->setTleEpoch(substr($line, 18, 14));
+
+                        var_dump($this->epoch->getTimeString());
+                        die();
+                        $ftdmm = substr($line, 33, 9); //TODO
+                        // TODO
+                        $valid[1] = true;
+                        break;
+                    case '2':
+                        $this->satelliteNo = trim(substr($line, 2, 5));
+                        $this->inclination = doubleval(substr($line, 8, 8));
+                        $this->raan = doubleval(substr($line, 17, 8));
+                        $this->eccentricity = doubleval('0.' . substr($line, 26, 7));
+                        $this->aop = doubleval(substr($line, 34, 8));
+                        $this->meanAnomaly = doubleval(substr($line, 43, 8));
+                        $this->meanMotion = doubleval(substr($line, 52, 11));
+                        $this->revolutionNoAtEpoch = intval(substr($line, 63, 5));
+                        $valid[2] = true;
+                        break;
+                    default:
+                        break;
+                }
+            }
+        }
+    }
+}

src/Calculations/SatelliteCalc.php

@@ -0,0 +1,166 @@
+<?php
+
+namespace Andrmoel\AstronomyBundle\Calculations;
+
+use Andrmoel\AstronomyBundle\AstronomicalObjects\Planets\Earth;
+use Andrmoel\AstronomyBundle\Constants;
+use Andrmoel\AstronomyBundle\Entities\TwoLineElements;
+use Andrmoel\AstronomyBundle\Utils\AngleUtil;
+use Andrmoel\AstronomyBundle\Utils\GeneralUtil;
+
+class SatelliteCalc
+{
+    public static function twoLineElements2keplerianElements(TwoLineElements $tle, float $T): array
+    {
+        $T0 = $tle->getEpoch()->getJulianCenturiesFromJ2000();
+        $M0 = $tle->getMeanAnomaly();
+        $n = $tle->getMeanMotion();
+        $d1mm = $tle->get1thDerivativeOfMeanMotion();
+        $d2mm = $tle->get2ndDerivativeOfMeanMotion();
+        $e = $tle->getEccentricity();
+
+        $dT = $T - $T0;
+
+        $M = self::getMeanAnomaly($tle, $dT);
+
+        $a = self::getSemiMajorAxis($tle, $dT);
+
+        var_dump($a);
+        die();
+
+        $E = self::getEccentricAnomaly($M0, $e);
+
+
+        var_dump("ECCC", $E);
+        die();
+        // TODO ...
+        return [];
+    }
+
+    private static function getMeanAnomaly(TwoLineElements $tle, float $dT): float
+    {
+        $M0 = $tle->getMeanAnomaly();
+        $n = $tle->getMeanMotion();
+        $d1mm = $tle->get1thDerivativeOfMeanMotion();
+        $d2mm = $tle->get2ndDerivativeOfMeanMotion();
+
+        $M = $M0
+            + $n * $dT
+            + $d1mm * pow($dT, 2)
+            + $d2mm * pow($dT, 3);
+
+        return $M;
+    }
+
+    public static function getTrueAnomaly(TwoLineElements $tle): float
+    {
+        $e = $tle->getEccentricity();
+        $E = self::getEccentricAnomaly($tle);
+
+        $ERad = deg2rad($E);
+
+        $ThetaRad = 2 * atan(
+                sqrt((1 + $e) / (1 - $e)) * tan($ERad / 2)
+            );
+
+        $Theta = rad2deg($ThetaRad);
+
+        return $Theta;
+    }
+
+    public static function getEccentricAnomaly(TwoLineElements $tle): float
+    {
+        $M = $tle->getMeanAnomaly();
+        $e = $tle->getEccentricity();
+        $MRad = deg2rad($M);
+
+        $Ei = $M + 0.85 * $e * GeneralUtil::sign(sin($MRad));
+
+        do {
+            $EiRad = deg2rad($Ei);
+
+            $Ej = $Ei - ($Ei - $e * sin($EiRad) - $M) / (1 - $e * cos($EiRad));
+            $Ei = $Ej;
+        } while (abs($Ei - $Ej) > 1e-8);
+
+        $Ei = AngleUtil::normalizeAngle($Ei);
+
+        return $Ei;
+    }
+
+    private static function getSemiMajorAxis(TwoLineElements $tle, float $dT): float
+    {
+        $n = $tle->getMeanMotion();
+        $nRad = deg2rad($n);
+        $d1mm = $tle->get1thDerivativeOfMeanMotion();
+        $d2mm = $tle->get2ndDerivativeOfMeanMotion();
+
+        $mu0 = sqrt(Constants::GRAVITATIONAL_PARAMETER);
+
+        $a0 = pow($mu0 / $n, 2 / 3);
+
+        var_dump($a1);die();
+
+        $a = pow($GM, 1 / 3) / pow((2 * $n * pi()) / 86400, 2 / 3);
+
+        return $a;
+    }
+
+    public static function getRightAscensionOfAscendingNode(TwoLineElements $tle, float $dT): float
+    {
+        $iRad = deg2rad($i);
+
+        $dOmega = -9.9641 * pow(Earth::RADIUS / $a, 3.5) * (cos($iRad) / (pow(1 - pow($e, 2), 2)));
+        $Omega = $Omega0 + $dOmega * $dT;
+
+        return $Omega;
+    }
+
+    public static function getArgumentOfPerigee(TwoLineElements $tle, float $dT): float
+    {
+        $iRad = deg2rad($i);
+
+        $dOmega = 4.98 * pow(Earth::RADIUS / $a, 3.5) * ((5 * pow(cos($iRad), 2) - 1) / pow(1 - pow($e, 2), 2));
+        $omega = $omega0 + $dOmega * $dT;
+
+        return $omega;
+    }
+
+    public static function getPerifocalCoordinateSystem(TwoLineElements $tle): array
+    {
+        $TRad = deg2rad($trueAnomaly);
+
+        $k = ($a * (1 - pow($e, 2))) / (1 + $e * cos($TRad));
+
+        $x = $k * cos($TRad);
+        $y = $k * sin($TRad);
+        $z = 0;
+
+        return [$x, $y, $z];
+    }
+
+    public static function fofo(): array
+    {
+        $x0 = 0;
+        $y0 = 0;
+
+        $aopRad = deg2rad($aop);
+        $raanRad = deg2rad($raan);
+        $iRad = deg2rad($i);
+
+        // Rotation matrix
+        $Px = cos($aopRad) * cos($raanRad) - sin($aopRad) * sin($raanRad) * cos($iRad);
+        $Py = cos($aopRad) * sin($raanRad) + sin($aopRad) * cos($raanRad) * cos($iRad);
+        $Pz = sin($aopRad) * sin($iRad);
+
+        $Qx = -sin($aopRad) * cos($raanRad) - cos($aopRad) * sin($raanRad) * cos($iRad);
+        $Qy = -sin($aopRad) * sin($raanRad) + cos($aopRad) * cos($raanRad) * cos($iRad);
+        $Qz = cos($aopRad) * sin($iRad);
+
+        $x = $Px * $x0 + $Qx * $y0;
+        $y = $Py * $x0 + $Qy * $y0;
+        $z = $Pz * $x0 + $Qz * $y0;
+
+        return [$x, $y, $z];
+    }
+}

src/Constants.php

@@ -7,4 +7,5 @@ class Constants
     // 299792.458 km/s
     public const LIGHT_SPEED_AU = 17314463348.4; // Speed of light in 10^-8 AU/day
     public const CONSTANT_OF_ABERRATION = 0.0056932; // degrees
+    public const GRAVITATIONAL_PARAMETER = 3.986005e14;
 }

src/Entities/KeplerianElements.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Andrmoel\AstronomyBundle\Entities;
+
+class KeplerianElements
+{
+    private $eccentricity = 0.0;
+    private $semimajorAxis = 0.0;
+    private $inclination = 0.0;
+    private $longitudeOfAscNode = 0.0;
+    private $argumentOfPeriapsis = 0.0;
+    private $trueAnomaly = 0.0;
+}

src/Entities/TwoLineElements.php

@@ -0,0 +1,74 @@
+<?php
+
+namespace Andrmoel\AstronomyBundle\Entities;
+
+use Andrmoel\AstronomyBundle\TimeOfInterest;
+
+class TwoLineElements
+{
+    const EPHEMERIS_TYPE_SGP4 = 0;
+    const EPHEMERIS_TYPE_SGP = 1;
+//    const EPHEMERIS_TYPE_SGP4 = 2;
+    const EPHEMERIS_TYPE_SDP4 = 3;
+    const EPHEMERIS_TYPE_SGP8 = 4;
+    const EPHEMERIS_TYPE_SDP8 = 5;
+
+    private $satelliteNo = '';
+    private $classification = '';
+    private $internationalDesignator = '';
+    private $epoch = null;
+    private $d1MeanMotion = 0.0;
+    private $d2MeanMotion = 0.0;
+    private $BSTARDragTerm = 0.0;
+    private $ephemerisType = '';
+    private $setNumber = 0;
+    private $inclination = 0.0;
+    private $rightAscensionOfAscendingNode = 0.0;
+    private $eccentricity = 0.0;
+    private $argumentOfPerigee = 0.0;
+    private $meanAnomaly = 0.0;
+    private $meanMotion = 0.0;
+    private $revolutionNoAtEpoch = 0;
+
+    public function __construct(array $tleData)
+    {
+        foreach ($tleData as $var => $value) {
+            $this->$var = $value;
+        }
+    }
+
+    public static function createFromTLEData(array $tleData)
+    {
+
+    }
+
+    public function getEpoch(): TimeOfInterest
+    {
+        return $this->epoch;
+    }
+
+    public function get1thDerivativeOfMeanMotion(): float
+    {
+        return $this->d1MeanMotion;
+    }
+
+    public function get2ndDerivativeOfMeanMotion(): float
+    {
+        return $this->d2MeanMotion;
+    }
+
+    public function getEccentricity(): float
+    {
+        return $this->eccentricity;
+    }
+
+    public function getMeanAnomaly(): float
+    {
+        return $this->meanAnomaly;
+    }
+
+    public function getMeanMotion(): float
+    {
+        return $this->meanMotion;
+    }
+}