predict_th.c

00001 /****************************************************************************
00002  *    Copyright 2010 Andy Kirkham, Stellar Technologies Ltd
00003  *    
00004  *    This file is part of the Satellite Observers Workbench (SOWB).
00005  *
00006  *    SOWB is free software: you can redistribute it and/or modify
00007  *    it under the terms of the GNU General Public License as published by
00008  *    the Free Software Foundation, either version 3 of the License, or
00009  *    (at your option) any later version.
00010  *
00011  *    SOWB is distributed in the hope that it will be useful,
00012  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  *    GNU General Public License for more details.
00015  *
00016  *    You should have received a copy of the GNU General Public License
00017  *    along with SOWB.  If not, see <http://www.gnu.org/licenses/>.
00018  *
00019  *    $Id: main.cpp 5 2010-07-12 20:51:11Z ajk $
00020  *    
00021  ***************************************************************************/
00022 
00023 #include "string.h"
00024 #include "sowb.h"
00025 #include "osd.h"
00026 #include "sgp4sdp4.h"
00027 #include "predict_th.h"
00028 #include "gps.h"
00029 #include "gpio.h"
00030 #include "satapi.h"
00031 #include "debug.h"
00032 
00033 #ifdef PREDICT_TH_RUN
00034 
00035 tle_t       ISS_TLE;
00036 
00037 
00038 
00039 int sgp4sdp4_th_init(void) {
00040     char buf[128];
00041     GPS_TIME t;
00042     double jd_epoch, jd_utc, tsince, phase;
00043     vector_t vel = { 0, 0, 0 };
00044     vector_t pos = { 0, 0, 0 };
00045     vector_t obs_set;
00046     geodetic_t obs_geodetic;
00047     geodetic_t sat_geodetic;
00048     tle_t tle, localtle;
00049     char elements[3][80];
00050 
00051     /* Prepare to begin ISS */
00052     strcpy(elements[0], "ISS (ZARYA)");
00053     strcpy(elements[1], "1 25544U 98067A   10278.19511664  .00012217  00000-0  97221-4 0   147");
00054     strcpy(elements[2], "2 25544 051.6473 027.7875 0007506 064.6316 006.5147 15.71651651680777");
00055     
00056     debug_printf("SGP4SDP4 TH starting 1\r\n");
00057     
00058     ClearFlag(ALL_FLAGS);
00059     Get_Next_Tle_Set(elements, &tle);
00060     memcpy(&localtle, &tle, sizeof(tle_t));
00061     select_ephemeris(&tle);
00062     
00063     gps_get_time(&t);
00064     
00065     if (!t.is_valid) {
00066         debug_printf("SGP4SDP4 TH Abort, invalid time.\r\n");
00067         return 0;
00068     }
00069     
00070     jd_utc = gps_julian_date(&t);
00071     jd_epoch = Julian_Date_of_Epoch(tle.epoch);
00072     tsince = (jd_utc - jd_epoch) * xmnpda;
00073     
00074     if (isFlagSet(DEEP_SPACE_EPHEM_FLAG)) {
00075         //debug_printf("Using SDP4\r\n");
00076         SDP4(tsince, &tle, &pos, &vel, &phase);
00077     }
00078     else {
00079         //debug_printf("Using SGP4\r\n");
00080         SGP4(tsince, &tle, &pos, &vel, &phase);
00081     }
00082 
00083     Convert_Sat_State(&pos, &vel);
00084     //SgpMagnitude(&vel); // scalar magnitude, not brightness...
00085     //double velocity = vel.w;
00086 
00087     GPS_LOCATION_AVERAGE loc;    
00088     gps_get_location_average(&loc);
00089     if (loc.east_west   == 'W') loc.longitude *= -1.;
00090     if (loc.north_south == 'S') loc.latitude  *= -1.;
00091 
00092     obs_geodetic.lat   = loc.latitude * de2ra; // * 56.1920;
00093     obs_geodetic.lon   = loc.longitude * de2ra; // * -3.0339;
00094     obs_geodetic.alt   = loc.height / 1000.;
00095     
00096     Calculate_Obs(jd_utc, &pos, &vel, &obs_geodetic, &obs_set);
00097     Calculate_LatLonAlt(jd_utc, &pos, &sat_geodetic);
00098 
00099     double azimuth     = Degrees(obs_set.x);
00100     double elevation   = Degrees(obs_set.y);
00101     double range       = obs_set.z;
00102     //double rangeRate   = obs_set.w;
00103     //double height      = sat_geodetic.alt;
00104     
00105     //sprintf(buf, "JD UTC : %.5f  JD SAT : %.5f  DIF : %f\r\n", jd_utc, jd_epoch, jd_utc - jd_epoch);
00106     //debug_printf("%s", buf);
00107     
00108     sprintf(buf, "ISS El:%.1f AZ:%.1f %dKm\r\n\n", elevation, azimuth, (int)range);
00109     osd_string_xy(0, 14, buf);
00110     debug_printf("%s", buf);
00111     return 1;
00112     
00113     
00114 }
00115 
00116 #endif
00117