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I am trying to model a multi-stage lunar mission with STK Astrogator. The vehicle separation happens after the first Trans Lunar Injection Burn. I've been trying to figure out how to arrange the Mission Control Sequence accordingly but I keep getting infeasible answers. Is there something that I am doing wrong?

I have included a screenshot of my MCS here. The main question I have is where should place the 'Follow' segment such that the satellite separates from the launch vehicle after TransLunarInjection?

Edit: More detail: The error that I am currently getting from STK is: Satellite trajectory intersects with Earth during Target_Sequence.ToSwingBy segment Collision occurred: (date I input).

Any help will be much appreciated! Thank you!

enter image description here

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    $\begingroup$ You can always edit your question to add or change things. Best to put all relevant stuff in the question body rather than in comments. $\endgroup$ Jan 31 '20 at 20:09
  • $\begingroup$ What exactly are you trying to simulate with the "Follow" segment? Are you trying to simulate both the upper stage and the satellite the entire way? You could add a small instantaneous propulsive segment to your sequence to simulate vehicle separation and then just assume your entire sequence is for the satellite (whether attached or not) $\endgroup$
    – Carlos N
    Feb 4 '20 at 17:52
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You aren't using the follow segment properly. A follow segment is normally used at the begging of the MCS to replace either a launch segment or an initial state. It grabs a state (or perhaps an entire ephemeris) from another satellite in STK and then propagates forward from that state according to the segments of the MCS. What you've done by putting the follow segment in your MCS, is changed the state of the spacecraft at that point to be whatever the follow segment is following. So you've started with your trajectory in the MCS using the launch, and then started over with the follow. You're creating a discontinuous MCS by doing this.

The way to do this correctly is to create another satellite, and have the follow segment be the first segment of that satellite. Then make the follow refer to your baseline satellite and have it give the state from wherever you want the separation to occur.

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