ommread

Read data from orbit mean-elements message (OMM) file

Since R2024a

Syntax

ommStruct = ommread(ommFile)

Description

ommStruct = ommread(ommFile) reads the data from an orbit mean-elements message (OMM) file, ommFile. The function outputs a vector of structures containing data from the input OMM file in tleStruct. You can then use the propagateOrbit function to calculate the position and velocity using ommStruct.

If the OMM file contains multiple entries for the same catalog number, the function outputs only the data corresponding to the latest epoch, which is defined for each OMM set.

Examples

Read Data from OMM File and Calculate Position and Velocity from Data

Read data from the OMM file 'eccentricOrbitSatellite.xml' and calculate the position and velocity of the satellite at 12:00:00 on May 10, 2020.

Read the data from the OMM file 'eccentricOrbitSatellite.xml', which is on the MATLAB^® path. The file is provided with Aerospace Toolbox.

ommStruct = ommread('eccentricOrbitSatellite.xml')

ommStruct = 
  struct with fields:

                             Name: "Satellite 41"
           SatelliteCatalogNumber: 20041
                            Epoch: 05-May-2020 13:51:55
                            BStar: 0
    RightAscensionOfAscendingNode: 30
                     Eccentricity: 0.7415
                      Inclination: 60
              ArgumentOfPeriapsis: 280
                      MeanAnomaly: 289.4697
                       MeanMotion: 0.0083

Calculate the position and velocity corresponding to the input time using the OMM data defined in ommStruct.

[r,v] = propagateOrbit(datetime(2020, 5, 10, 12, 0, 0),ommStruct);

Input Arguments

ommFile — OMM file

character vector | string scalar

OMM file, specified as a character vector or a string scalar. The file must exist in the current folder or in a folder on the MATLAB path, or the argument must include a full or relative path to a file. You can then use the propagateOrbit function to calculate the position and velocity of one or more spacecraft over time using the orbits defined in ommStruct. This function supports the .xml and .json OMM file formats. For more information on OMM files, see Orbit Mean-Elements Message (OMM) File.

Example: 'eccentricOrbitSatellite.xml'

Data Types: char | string

Output Arguments

ommStruct — OMM structures

vector of structures

OMM structures extracted from ommFile, returned as a vector of structures. To calculate the position and velocity of one or more spacecraft over time using Orbit Mean-Elements Message (OMM) data, use this vector of structures as an input to the propagateOrbit function.

For more information on OMM file structures, see Orbit Mean-Elements Message (OMM) File. If the OMM file contains multiple entries for the same catalog number, the function outputs only the data corresponding to the latest epoch, which is defined for each OMM set.

Field Name	Description	Unit
Name	Name of the satellite.	N/A
SatelliteCatalogNumber	Unique satellite identifier	N/A
Epoch	Reference time of the orbital elements	datetime
BStar	Drag term	1/(Earth radii)
RightAscensionOfAscendingNode	Longitude of ascending node	degrees
Eccentricity	Orbital eccentricity	N/A
Inclination	Orbital inclination	degrees
ArgumentOfPeriapsis	Argument of periapsis	degrees
MeanAnomaly	Mean anomaly	degrees/second
MeanMotion	Mean motion	degrees/second

Version History

Introduced in R2024a