Flyby-only grand tour

[MedwedianPresident]

There is an increasing trend of using flyby maneuvers like in real life, but there also is the everlasting tradition of the grand tour in Kerbal Space Program. I have decided to make a little feasibility study/challenge which combines both concepts in an interesting way.

Your tasks are:

1. Prove that it is possible to plot a trajectory that passes through the SOI's of all stock (all OPM/Real Solar System/planet pack of your specification) planets without midcourse corrections. Only a single Kerbin ejection burn may be made, it's about gravity assists from then on. You must change the maximum number of patched conics iterations in the settings file in order to plan the flight. I don't care if you use HyperEdit because I want to see if it is possible at all. It is especially interesting if you have Principia installed. It is enough if every planet is approached a single time, e.g. no return to Kerbin is required. However, I think that multiple flyby maneuvers of the same planet may be needed. You do not need to execute the mission, I only need to see the picture of the trajectory.

2. Document the trajectory in full detail - tell me the exact date, phase angle and DV of the ejection burn and the order of the gravity assists as well as the respective flyby periapses if you can. Also tell me the duration of the mission if you can.

 

Good luck!

[Thor Wotansen]

This challenge is very possible from a mathematical standpoint, however you won't get the trajectory line in KSP to do that.  The patched conics used by the game engine cause errors on distant node and SOI changes.

[322997am]

I would like to modify the rules as the game glitches the course a bit resulting in my path flailing all over the place. Allow us to make correction burns

[Teilnehmer]

The problem MedwedianPresident sets is too complicated even letting alone the trajectory errors.

I’d suggest the following reformulation of the challenge rules:

• burns are permitted;
• the tour with the least total Δv wins.

So we could approach the problem gradually. Every next participant would try to make their total Δv less, and eventually, we would come near the lower bound.

[Mukita12]

On 10/16/2017 at 12:55 PM, Teilnehmer said:

The problem MedwedianPresident sets is too complicated even letting alone the trajectory errors.

I’d suggest the following reformulation of the challenge rules:

• burns are permitted;
• the tour with the least total Δv wins.

So we could approach the problem gradually. Every next participant would try to make their total Δv less, and eventually, we would come near the lower bound.

that would be possible if you using RO And RSS

But it was impossible to do this on stock

[Teilnehmer]

4 hours ago, Mukita12 said:

that would be possible if you using RO And RSS

Wow.

[Teilnehmer]

On 10/24/2017 at 8:15 PM, Mukita12 said:

that would be possible if you using RO And RSS

But it was impossible to do this on stock

Could you please share your considerations?

[Mukita12]

29 minutes ago, Teilnehmer said:

Could you please share your considerations?

yEAH I WILL

 

 

(My keyboard)

[MinimalMinmus]

This challenge is most definitely possible with a few burns. Bradley Whistance did it with a SSTO, and yes, with no refuel AT ALL until he came back to Kerbin.

With no burn, I'd say impossible. With such a small margin, then due to the butterfly effect, and supposing such a "mega flyby" trajectory even exists, then you could imagine a 1mm error for the Moho Flyby results in a 1m error for the Eve/Gilly flyby, resulting in a 1 km error for the Duna flyby, and 1 Mm for Dres. While those numbers are probably false, the accumulated, exponential error would end in a complete fail in meeting the four moons of Jool, and subsequently Eeloo.

And 1 mm would be very, VERY small compared to the scale between planets. It's in fact much less than the errors accumulated due to floating-point errors or even small glitches in the physics system (say, you are accounted to leaving Kerbin's SOI a few milliseconds later).

So here's my verdict: impossible without, very definitely possible with, even with no refuel or staging.

[Mukita12]

On 10/27/2017 at 3:01 PM, Teilnehmer said:

Could you please share your considerations?

If the challenge say you can't burn for next flyby that's mean we can't change angle from where we launch 

Remember on Ksp every planet has different Inclination 

[Teilnehmer]

I don’t quite understand. The inclination can be changed during a fly-by. Of course, there are lots of constraints how it can be changed. But it’s not obvious for me why the challenge is impossible in the stock KSP (letting alone the butterfly effect mentioned by@MinimalMinmus of course).

And what’s different in the real Solar system?

Edited November 1, 2017 by Teilnehmer

[Mukita12]

Just now, Teilnehmer said:

I don’t quite understand. The inclination can be changed during a fly-by. Of course, there are lots of constraints how it can be changed. But it’s not obvious for me that the challenge is impossible in the stock KSP (letting alone the butterfly effect mentioned by@MinimalMinmus of course).

And what’s different in the real Solar system?

In RSS Once you get the right Planetary Alignment You can Do this With just little correct burn if you want go closer to planet

[Teilnehmer]

Could you elaborate / demonstrate what you mean?

[Mukita12]

Just now, Teilnehmer said:

Could you elaborate / demonstrate what you mean?

watch BevolJ Outer Planet Grand tour and Tyler Raiz Voyager 2 on Youtube and you get what i mean

[MinimalMinmus]

The other main problem I see, past the problem of it being a chaotic system, is that it takes a very specific configuration to manage to do exactly what you want.

Example:

I decide to start with a KEKKJ trajectory, visiting Kerbin, Mun, Minmus, Eve, and Gilly before heading to Jool.

First, the "Gravitational assistance-a-holics" of yours know you must get the Mun in a very specific position.

BUT you must also wait for Minmus to be here, hopefully not too close, as it would bother you.

Then you come to Eve, hopefully grabbing Gilly on the way (which is %@#$£ hard, by the way).

Now, you come back to Kerbin twice, while praying Mun or Minmus won't ruin any of your passes.

... And as a Bouquet Final, you must pray for Jool to be right where you want!

(and in fact, also hope Tylo is right where you want, to get into the system)

Such a combination of constraints is only possible very, very rarely. And while there are other routes, of course, they all have this batsh*t insane timing requirement.

[Mukita12]

34 minutes ago, MinimalMinmus said:

The other main problem I see, past the problem of it being a chaotic system, is that it takes a very specific configuration to manage to do exactly what you want.

Example:

I decide to start with a KEKKJ trajectory, visiting Kerbin, Mun, Minmus, Eve, and Gilly before heading to Jool.

First, the "Gravitational assistance-a-holics" of yours know you must get the Mun in a very specific position.

BUT you must also wait for Minmus to be here, hopefully not too close, as it would bother you.

Then you come to Eve, hopefully grabbing Gilly on the way (which is %@#$£ hard, by the way).

Now, you come back to Kerbin twice, while praying Mun or Minmus won't ruin any of your passes.

... And as a Bouquet Final, you must pray for Jool to be right where you want!

(and in fact, also hope Tylo is right where you want, to get into the system)

Such a combination of constraints is only possible very, very rarely. And while there are other routes, of course, they all have this batsh*t insane timing requirement.

Exactly

[Helmetman]

I don't get the 

On ‎15‎/‎10‎/‎2017 at 10:04 AM, MedwedianPresident said:

 Only a single Kerbin ejection burn may be made, it's about gravity assists from then on.

Attitude control propellant was used on i.e. the Voyager spacecraft using Hydrazine for the 'necessary' course corrections to go from Jupiter, Saturn > > >
Is this challenge a test to see what can be done in ksp as it has been done in real life? Okay. It hasn't been done in real life, thus. So it's pure a KSP challenge and impossible to execute when patched conics errors the ballistics of your vessel upon SOI change. 

Obviously the challenge is about testing the gravity assist skills of other players. I'm all for such a thing, just think of something differently.
A thought from the top of my head is to create a pre specced vessel (of your making) with a set but very scarce amount of fuel and then see which player gets it the furthest.
EDIT: by furthest I mean how many SOI changes each respective user can manage.
 

Edited November 4, 2017 by Helmetman

[MinimalMinmus]

20 hours ago, Helmetman said:

Is this challenge a test to see what can be done in ksp as it has been done in real life? Okay. It hasn't been done in real life, thus. So it's pure a KSP challenge and impossible to execute when patched conics errors the ballistics of your vessel upon SOI change.

Well, as I said, it's probably possible, but "possible" in the sense of "Landing on Tylo with one hand while you complete Sonic Wave in Geometry dash while blindfolded, while completing a 35x35x35 rubik's cube with your feet, while bellydancing perfectly, reciting the entirety of Hamlet and composing a piece for symphonic orchestra is possible". It is not impossible in the sense that it contradicts no physical law, but it is still pretty much so.

Edited November 5, 2017 by MinimalMinmus