beyond 0.9

Flight Dynamic Library

This library was started to better understand how Flight Dynamics works. It has no intent of efficiency nor performance at the moment, and the goal is mainly to develop a simple API for space observations.

The sources of this library can be found on codeberg and are under the MIT license.

Installation

Beyond requires Python 3.7+, numpy and sgp4. To install the library and its dependencies use pip

pip install beyond

Documentation

• Last release (stable)

• Dev (latest)

Usage

import numpy as np
from beyond.io.tle import Tle
from beyond.frames import create_station
from beyond.dates import Date, timedelta


# Parse TLE
tle = Tle("""ISS (ZARYA)
1 25544U 98067A   19072.15347313  .00000167  00000-0  10147-4 0  9997
2 25544  51.6420 118.6717 0004098  99.2855 123.2259 15.52799885160336""")

# Create a station from which to compute the pass
station = create_station('KSC', (28.524058, -80.65085, 0.0))

for orb in station.visibility(tle.orbit(), start=Date.now(), stop=timedelta(days=1), step=timedelta(minutes=2), events=True):

    # As all angles are given in radians,
    # there is some conversion to do
    azim = -np.degrees(orb.theta) % 360
    elev = np.degrees(orb.phi)
    r = orb.r / 1000.

    print("{event:10} {tle.name}  {date:%Y-%m-%dT%H:%M:%S.%f} {azim:7.2f} {elev:7.2f} {r:10.2f}".format(
        date=orb.date, r=r, azim=azim, elev=elev,
        tle=tle, event=orb.event if orb.event is not None else ""
    ))

    # Stop at the end of the first pass
    if orb.event and orb.event.info == "LOS":
        break

This library is used as basis for the Space-Command utility.

Commons usages for this library are:

• Predicting of satellite visibility

• Computing satellite ground track

• Computing planets visibility

Tests

Beyond is provided with a lot of unit tests. They can be run with pytest and/or tox. The code coverage is around 92%.

References

A lot of the formulas and flight dynamic algorithm are based on Vallado’s Fundamentals of Astrodynamic and Applications 4th ed.