benelsen / SAASGP4.jl

WIP

SAASGP4

SAASGP4.jl is a thin Julia wrapper for the SAA (Standardized Astrodynamic Algorithm) SGP4 library.

Installation

SAASGP4.jl currently only works on x86_64 Linux and you might need to install libiomp5 and/or libiomp-dev.

The package is currently unregistered, but can be installed through clone:

Pkg.clone("https://github.com/benelsen/SAASGP4.jl")

Usage

using SAASGP4

# load the TLE using strings
satkey = SAASGP4.tleAddSatFrLines(
    "1 90021U RELEAS14 00051.47568104 +.00000184 +00000+0 +00000-4 0 0814",
    "2 90021   0.0222 182.4923 0000720  45.6036 131.8822  1.00271328 1199")

# initialize the loaded TLE
SAASGP4.sgp4InitSat(satkey)

# parse the start time from a DTG string into a float of days since 1950
starttime = SAASGP4.DTGToUTC("00051.47568104")

# initialize the arrays to store the propagated positions, velocities etc.
poss = Array{Array{Float64, 1}, 1}()
vels = Array{Array{Float64, 1}, 1}()
llhs = Array{Array{Float64, 1}, 1}()
mses = Array{Float64, 1}()

# propagate the TLE for 10 days in 1/2 day increments
for ds50UTC in starttime:0.5:(starttime + 10)
    pos, vel, llh, mse = SAASGP4.sgp4PropDs50UTC(satkey, ds50UTC)
    push!(poss, pos)
    push!(vels, vel)
    push!(llhs, llh)
    push!(mses, mse)
end

# remove the TLE from memory
SAASGP4.sgp4RemoveSat(satkey)
SAASGP4.tleRemoveSat(satkey)

License

The underlying SGP4 library is non-export controlled, but subject to the SGP4 Open License Agreement.

The wrapper itself is licensed under the MIT "Expat" License.