Checking trajectory of a craft

[enjoystastycheeses]

I'm playing around with creating Apollo missions and I'm trying to have the actions be performed in the correct order:

1. Orbit
2. Transmunar Injection
3. MEM extraction

However, I'm having a hard time figuring out a way of having the game check the trajectory of the craft. There doesn't seem to be "on an escape trajectory out of x" or "has encounter with x" node so I'm wondering what other people are doing to validate these checks.

Ie:

• IF "Encounter = Mun" or "On escape trajectory from Kerbin (towards Mun)"
• THEN "Show dialog box to extract MEM"

Is this possible at the moment?

[Hurzelgnurk]

My dirty workaround was based on AP height around Kerbin. If I tried anything with the mun it counts only after you reach the soi and thats a bit late for transposition and docking.

[MulleDK19]

Maybe the sphere of influence check node? Or that combined with a velocity test.

[enjoystastycheeses]

5 hours ago, MulleDK19 said:

Maybe the sphere of influence check node? Or that combined with a velocity test.

 

12 hours ago, Hurzelgnurk said:

My dirty workaround was based on AP height around Kerbin. If I tried anything with the mun it counts only after you reach the soi and thats a bit late for transposition and docking.

 

I considered Apo/Velocity/Distance from Kerbin/Surface height but these would be triggered in any direction. I could head to Duna (on an Apollo mission) and start triggering subsequent nodes.

SOI check isn't ideal as you're basically already there and that's not a "realistic" recreation.

[MulleDK19]

11 minutes ago, enjoystastycheeses said:

SOI check isn't ideal as you're basically already there and that's not a "realistic" recreation.

There's a "Left SOI" node.

[enjoystastycheeses]

1 hour ago, MulleDK19 said:

There's a "Left SOI" node.

I think when it comes to going to the Mun, you both exit Kerbin SOI and enter Mun SOI instantly so that leaves me in the same spot..

[StrikeEagleCC]

How about the "Orbit Parameters" node? If you have en encounter in your trajectory, say the Mun from Kerbin, can that node detect a periapsis inside the Mun SOI before you get there?

[Hurzelgnurk]

Does not seem to count as the orbit parameter until you reach soi. Mun orbit parameters like  45000m>pe>35000m only get a positive when you are in soi of mun so we are still left at that way too late point in time.

[Ker Ball One]

The way I did it is by knowing the precise escape velocity for the specific expected starting orbit.

The check velocity node can be set to reference orbital velocity.   So if you first check for orbital parameters with zero inclination, zero eccentricity, and 150 km apo and peri... The escape velocity will always be the same.