I am simulating the example of LEO station keeping in GMAT with a delta-v thrusters of 2.5m / s, my question is how can I determine the time in which the thrusters act to raise the height of the orbit and thus maintain the orbit ?

The graph shows the elapsed seconds on the X axis, and the height in km on the Y axis.

I think that the time it takes to raise the height of the orbit is the blue line that I draw, am I correct?

enter image description here

EDIT: I add data for better clarity: The report of the result of the simulation (during the firing of the propeller to raise the orbit) is as follows:

enter image description here

The first column "LEOsat.ElapsedSecs" shows the elapsed time

The second column "LEOsat.Earth.Altitude" is the altitude of the satellite

The third column "TCM1.Element1" is the delta-v of the thruster for raises the orbital apogee

The fourth column "TCM2.Element1" is the delta-v of the thruster to circularize the orbit

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    $\begingroup$ I think there may be some details you need to share here as well. If you are running the simulation yourself, can you include the specific parameters that you've used? GMAT probably has more than one way to do this, can you name the options you've used? Thanks! $\endgroup$
    – uhoh
    Aug 9, 2020 at 14:39
  • $\begingroup$ Is the y axis altitude and the x axis elapsed time? If so, in what units? If so, why should thruster firing correspond to instantaneous altitude? (To raise perigee efficiently, you thrust while at apogee, etc.) $\endgroup$ Aug 9, 2020 at 22:26
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    $\begingroup$ I fear, this will be another "Play Kerbal Space Program to understand, what you are doing" Post ;-) .... The Blue Line you draw is the orbits altitude from the last perigee before you turn on your engines till the first apogee after you shut down your engines. It seams like the shown manouvre(s) is/are a/two instantanious one(s) at the perigee and a second one at apogee. $\endgroup$
    – CallMeTom
    Aug 10, 2020 at 5:38
  • $\begingroup$ Sorry, edit the question to add data $\endgroup$ Aug 10, 2020 at 6:07
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    $\begingroup$ Unfortunately, the blue line isn't what you think. You can always see the oscillations in height because the orbit is sligthly elliptical. Low is perigee, high is apogee. You need to calculate the difference between old and new perigee and old and new apogee to get the change in kinetic energy, then use the thrust to work out how long the burn was.Its not the blue line. the blue line is half an orbit - from old perigee to new apogee. They can coincidentally be the same, but I doubt it. $\endgroup$
    – Polygnome
    Aug 10, 2020 at 8:51


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