TransX TransX planning - IMFD burning : how to burn in IMFD a transX plan ?

potjoe

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VX: -1738.66
VY: -11821.3
VZ: -556.655

Looking at it, I can already tell you it won't work : these state vectors seems to be relative to a sun-centered trajectory (they're all negative). However, you cannot use them to perform an ejection burn, because when you're ejecting, you're still under Earth's SOI, so to speak you're still referencing the Earth. This is why on IMFD you're setting your plan in the course Program, and then you have to use the Orbit eject program which "converts" your sun-centered velocities to earth-centered velocitites.

Is there a specific thread where you're following the development of your program ? I'd like to keep your work under an attentive eye ;)
 

Marijn

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Looking at it, I can already tell you it won't work : these state vectors seems to be relative to a sun-centered trajectory (they're all negative).

The data also includes a list of bodies which are orbited:
399,10,299,299,10,499,499

Earth is 399, sun is 10 etc.

So it seems the data is bound to a body being orbited.

The state vectors also inlude RX, RY and RZ. I don't know what they mean.

Would this change things?

Is there a specific thread where you're following the development of your program ? I'd like to keep your work under an attentive eye ;)

Not yet, but I am getting close to a first version. It's a web-app, so I can send you a link to check it out.
 

potjoe

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I've looked in Rx values, doesn't seem to help a lot here...

Sure I would be pleased to have have a look on your project ;)
 

Tommy

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I am aware of this behaviour actually, but does it mean that TransX Plan is not reliable or even doable because of its inacurracy ? I mean... to me the main objective is to be able to plan everything I can before take-off, and then proceed with that plan. Is it just fantasy haha ?!
The TransX plan isn't perfect, but it's the best tool currently available for planning slings. The inaccuracies are small enough to be corrected with fairly small MCC's.

This part has lost me... I'm not able to find all these numbers in Tx. I might seem blind, but i'm just really confused.
If Tx gives me before the ejection burn an "Inc" value and a "Focus PeD", these numbers are no longer available after departure, since the displayed trajectory in Slinghot view isn't the planned one but the current one. Moreover, since I am not able to eject using IMFD Delta-v program in order to match perfectly both Inc. (which stands for Rinc and not EqI in IMFD right?), PeD, and Pe MJD between Tx plan and what IMFD'Map shows me, these values are changing in TransX during the trip (since the Pe MJD has changed too) ! So when I'm performing MCCs, i'm totally guessing the swing-by date and attitude I need to correct for. !
Very simple solution for this, involves a pencil and paper. As you plan the trip in TransX, write down the values. Use those values for the MCC's, ignoring what TransX is telling you after the ejection.

For the first part, as I said above, once I ejected i cannot find out what the Distance and Inclination correct values are supposed to be since TransX displays the current trajectory, and not the planned one. Where can I find these values ?
Finally, I don't know in which thread i've read it, but can't we use the planet approach program in order to set up both PeD Pe MJD and Rinc ?!
Planet Approch only works once you are very close to the planet's SOI, by which time the correction requires a lot of dV. Using Delta-V and Map you can fine tune the approach much farther out when it's more efficient.
 
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Marijn

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I've looked in Rx values, doesn't seem to help a lot here...

Sure I would be pleased to have have a look on your project ;)

Hi Potjoe,
It took a little longer than anticipated, but I got a more or less working version I'd like you to have a look at. Do you have some spare time? It's working as intended in Google Chrome only at the moment.
 

potjoe

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Hi Marjin,

A bit busy at the moment, but PM me the link, I'll try to have a look when I have some time today and during following days.
 

Marijn

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.. but PM me the link
Link and some explanation sent. Let me know what you think or run into.

---------- Post added at 07:31 PM ---------- Previous post was at 06:39 PM ----------

Oh. I forgot about a little change I made a long time ago affecting the total crew mass of a fully manned XR5. I am using XRSound and not UMMU which somehow results in a little different total crew mass.

I can't change this quickly now, but if you give crewmember Teal'c a mass of 54 instead of the default 104, the total crew mass should become 1224. Then all delta-v calculations on the screen should be confirmed by BurnTimeCalc upon scenario load.

---------- Post added 01-15-19 at 07:15 PM ---------- Previous post was 01-14-19 at 07:31 PM ----------

Hmm. I noticed we share the same user profile.. Will fix that when you are finished having a look..
 
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