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Fire-and-forget tourists to LKO and back


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The challenge is simple: make a Fire-and-forget rocket that sends tourists to LKO and back.

Spoiler

An incredibly lazy backstory

 

Due to budget cuts, the KSP has found itself with no qualified pilots whatsoever. To rectify the situation, they need to get money, fast. Gene has an idea: Space tourism! There are lots of Kerbals which will pay big Kerbucks to go to space. Unfortunately, to build a rocket to do this, they must sell all their probe cores to get the money -- They already owe the KerBank and Mafia thousands. Hence, the KSP requires an uncontrolled rocket to do tourism missions.

 

If someone comes up with a better one, msg me. If I like it, I will put it here :)

RULES

  • No shenanigans. Shenanigans are allowed, but will put you in a separate category.
  • Tourists must come home safe. It doesn't need to recover itself.
  • No control of the craft whatsoever after launch. Optimally, there would be no probe core or crew pod the craft. (You may put tourists in a crew pod)
  • Orbit is "PE > 75km"
  • You may do whatever you want on the pad; no input after you leave the pad -- Bill has a quadcopter you can take apart for it's R/C circuits.
  • No alt+F12 menu

 

CATEGORIES

  • Stock - 100% stock install. KER & other informational mods are allowed to show your orbit in screens.
  • KOS - Stock with KOS installed. All other rules apply. (Trivially easy, so not very interesting...)
  • Shenanigans - KOS or Stock, but you can do things like using cannons on the pad.
  • Modded - All mods are allowed, except cheaty mods like hyper edit. Too easy.
  • Lo-tech - Tier 3 or lower. You can use KOS if it's doohickey is tier 3 or lower.

If KOS's doohickey is >= Tier 3 you can use it.

 

SCORING

score = [Mass on the pad] / [# tourists].

Lowest score wins.

e.g., 50 tons & 10 Kerbals = 50/10 = 5.  50 tons and 5 Kerbals = 50/5 = 10

 

Stock highscore: ICMM ∞

KOS highscore: ICMM ∞

Shenanigans highscore: ICMM ∞

Lo-tech highscore: ICMM ∞

Modded highscore: ICMM ∞

 

More scores

Spoiler

Stock

Spoiler

Nothing yet...

KOS

Spoiler

Nothing yet...

Shenanigans

Spoiler

Nothing yet...

Lo-tech

Spoiler

Nothing yet...

Modded

Spoiler

Nothing yet...

 

 

My entry

I will do this later today!

 

SUBMIT

  • Preferably, record a video. OBS works well and is free.
  • If you submit an album... Honor system. 
  • Craft file should be supplied so we can confirm that it works.

BADGE

If someone would make one, that would be awesome! Separate badges for each category, please.

Edited by icantmakemodels
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What do you mean by "fire and forget"? Can we have any control on the craft after the launch?

If no, then I think a stock entry would be very very hard to do...

 

EDIT: Mostly because we probably need to stage and at least we need to initiate the de-orbit burn seperately I think.

 

Altough now that I think of it, it could be possible to have 1 engine pointing the wrong directions with low thrust that is fired on the launch. Then the main engines run out of fuel once it has reached stable orbit and the 1 engine pointing retrograde would do the deorbit burn... Interesting

EDIT2: But then again tier 3 technology makes that quite hard to achieve since you would need to be able to build an SSTO with all that extra weight added... So probably still quite impossible

EDIT3: Just realised that low-tech seems to be its own category so I'll probably try to do a stock entry without that tech restriction to see if it is possible :P

Edited by tseitsei89
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3 hours ago, icantmakemodels said:

@tseitsei89: Yes, no control of the craft after launch. I don't really expect the stock category to be possible, but it's there for completeness sake.

 

I don't have the skill for it, but a perfect gravity turn with something like an Ant pointing retrograde seems like it would work.  Does it have to make a full orbit, or (like the tourism contracts) only have to pass the 70 km PE mark?

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Getting to orbit - doable

Deorbit - doable

Actually landing alive - don't know how I could do that...

I cheated a little tough even to achieve these results. I clicked 'hold prograde' on SAS immediately after the launch but other than that no input.

 

The problem is the landing. I can't use chutes because I can't open them :P

I thought about using the big heatshield and lithobraking but the drag of the heatshield made unable to get to orbit and I couldn't find a way to fix it + I don't even know if the heatshield would slow me down enough on the way down...

If someone can actually do this I will be seriously impressed :)

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I believe a stock "fire and forget" rocket has never been attempted. EVER. This challenge will surely be interesting.

Creating a vessel which only needs 1 push of the spacebar is rather possible. RAPIERS, heavy rocket with gravity turning, all possible! Returning can be done through a small engine pointing retrograde, with a heat shield behind it.

5 hours ago, tseitsei89 said:

The problem is the landing. I can't use chutes because I can't open them :P

I thought about using the big heatshield and lithobraking but the drag of the heatshield made unable to get to orbit and I couldn't find a way to fix it + I don't even know if the heatshield would slow me down enough on the way down...

Firstly, update 1.2 has allowed parachutes to deploy automatically, without control, without the "when safe" mode.

Secondly, the drag of the heat shield shouldn't make it problematic to go to orbit. I've tried it before, and so far it controls easily and just seems like a flat surface. I could do a test, @tseitsei89, if you still feel unconfident about drag?

Edited by EliteGuy3
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I use a nose come on a heat shield for launch, it burns off harmlessly on reentry... that said I don't know how I'd get a landable craft with no input post launch, maybe with mechjebs new scripting features! probably cheating tho :$

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4 hours ago, EliteGuy3 said:

 

Firstly, update 1.2 has allowed parachutes to deploy automatically, without control, without the "when safe" mode.

Secondly, the drag of the heat shield shouldn't make it problematic to go to orbit. I've tried it before, and so far it controls easily and just seems like a flat surface. I could do a test, @tseitsei89, if you still feel unconfident about drag?

For your first point: Yes you are correct but what do you think will happen if I put the chutes to deploy on first stage (the only place where I could possibly deploy them in this challenge)? That's right they immediately deploy on launch since we are on safe speed and altitude... And if I don't deploy them there I can't deploy them at all...

For your second point: Yes I know that you can get to orbit (quite easily) with the big inflatable heatshield deployed from the start BUT I was unable to make that happen without input after the launch. Someone else might be able to do it tough. And also because of the drag the craft becomes heavier and it might be that the heatshield will not be draggy enough to slow the craft down enough to save the kerbal...

But if you have any more ideas for the landing part please keep them coming :)

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1) parachutes have been deployable, but remain stowed until their settings determine since about 0.90 I believe. You can trigger them in space just fine. With the 1.0 physics the settings don't have the range to do this reliably though.

2) LKO is a stable orbit. Learn Newtons 1st law. Without kOS or RemoteTech, this is impossible. Even mechjeb cant do this.

3) The lowest tier you can get a kOS part is 4, not 3. The lowest tier you can get a non-commandable kerbal carrying container is 4, not 3. Unless youre counting from 0 for some reason, I suggest you fix this.

4) The guidlines for challenges suggest you propose your own effort as well. If you'd done this, you'd have seen all these problems.

Just for fun, I did it anyway, with a launch weight of ~30t carrying 5 kerbals. Using a proper zero-lift turn and a tier 4 kOS unit and 2x tier 4 cabins, it wasn't difficult. I don't expect this to be included in the results.

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Without a mod like KOS or MJ this challenge is not within the realms of reasonable possibilities.

From launch to orbit without any input (after the obvious lift-off) is possible with careful design.
Returning from orbit to the surface is also possible. After the initial command to start the de-orbit process that is.
From launch to orbit to landing is not. Somewhere in orbit you'll have to issue a command. Either to flip the ship around or to ignite an engine.

The ONLY way to come close to this without a pilot mod is to ignite the de-orbit engine AT LAUNCH and have the main launch engine run dry once it reaches orbit. And to do this with only tier 3 tech? Let's summarize this challenge in just two letters: NO.

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Technically there is one way to do it without MJ or kOS or kRPC but it requires such perfect math that it's not doable except by accident unless you have something to calculate that math with (like MJ, kOS, or kRPC).  That way is this:

Get a stable orbit, but one with a very high apapsis that gets near the mun's orbit, but doesn't encounter it *yet*.  This is a stable orbit *for now*.

Wait serveral orbits until it does sync up with the Mun.

Have timed it just right so the Mun deflects the orbit enough to put it on a re-entry path back to Kerbin.  Now the orbit is no longer a stable orbit, and it can re-enter.

Of course there's NO WAY to calculate the timing properly to do any of that without pulling the precise numbers out of the KSP API which the stock user interface doesn't tell you.  Which means needing one of those mods.  So technically it's possible in stock, but only by completely lucky coincidence of happening to get the timing right.

Again, this feels like it violates the rule "prove it's possible by having a success at it yourself before posting it."

[Edit : Well I suppose there is one other very weird way, but definitely not at low tier.  Have an engine that requires electricity (i.e. xenon).  Have solar panels only on one side of the craft.  Use careful orientation of the rocket (no idea how to force it to be rolled the way you want without control) such that those solar panels are dark when you reach orbit.  Then have it situated so they enter the light half an orbit later (i.e. launch at night).  Now they can cause the engine to start working, thus giving you the delayed activation you need to make a de-orbit after having been in a stable orbit.)

Edited by Steven Mading
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1 hour ago, Steven Mading said:

Technically there is one way to do it without MJ or kOS or kRPC but it requires such perfect math that it's not doable except by accident unless you have something to calculate that math with (like MJ, kOS, or kRPC).  That way is this:

Get a stable orbit, but one with a very high apapsis that gets near the mun's orbit, but doesn't encounter it *yet*.  This is a stable orbit *for now*.

Wait serveral orbits until it does sync up with the Mun.

Have timed it just right so the Mun deflects the orbit enough to put it on a re-entry path back to Kerbin.  Now the orbit is no longer a stable orbit, and it can re-enter.

Of course there's NO WAY to calculate the timing properly to do any of that without pulling the precise numbers out of the KSP API which the stock user interface doesn't tell you.  Which means needing one of those mods.  So technically it's possible in stock, but only by completely lucky coincidence of happening to get the timing right.

This is really stretching the realm of possibilities. I agree in theory it IS possible but the margin of error are absolutely minimal.

1 hour ago, Steven Mading said:

Again, this feels like it violates the rule "prove it's possible by having a success at it yourself before posting it."

[Edit : Well I suppose there is one other very weird way, but definitely not at low tier.  Have an engine that requires electricity (i.e. xenon).  Have solar panels only on one side of the craft.  Use careful orientation of the rocket (no idea how to force it to be rolled the way you want without control) such that those solar panels are dark when you reach orbit.  Then have it situated so they enter the light half an orbit later (i.e. launch at night).  Now they can cause the engine to start working, thus giving you the delayed activation you need to make a de-orbit after having been in a stable orbit.)

You forgot that engines produce electricity. As long as the regular launch engine is lit, the descent ion engine is too.

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@Tex_NL and @Steven Mading

First of all: I agree with you that this is probably impossible but for a different reason than you do.

Secondly: Read the challenge properly

The OP is saying that there are different categories. One category where you can use kOS and one category where you use fully stock AND a third category where you (I would guess) you can use kOS BUT can only use 3rd tier or lower tier parts. So in stock category you can use any stock parts you like.

Thirdly: Please explain why getting to orbit and doing a deorbit burn would be impossible in stock with no input after the launch? I'll next try to explain why it is possible. What I think is impossible is actually landing the kerbal alive...

Ok so I'll start listing problems that I can see and how to solve those:

1. You need to tilt you craft away from vertical to ever reach orbit. Answer: tilt it just a little in the beginning and use just the right twr and let the gravity turn gently tilt you more and more towards horizontal.

2. Twr grows when fuel burns and you can't stage to switch to smaller engines. Answer: Build your craft so that the fuel on some engines runs out at specific times so your twr is reduced allowing you to hold a correct twr for your gravity turn.

3. You can never reach stable orbit if you just do a burn below 70km since your Pe will always be <70km. Answer: You need a burn time long enough so that you craft will be above 70km and still burning. That is why you probably need some really low twr long burning last stage so that you can keep burning and just drift upwards until you reach space and then still keep burning until you reach orbit.

4. You can't deorbit. Answer: You put some very low thrust engine on the front end of your craft pointing "the wrong way" that burns longer than your other engines. That way once you reach orbit your other engines stop but this one engine is still burning the opposite direction and will lower your Pe back to atmosphere if designed well enough.

If you have some others or if you weren't satisfied with my answers above please ask and I'll try to explain more/better. And remember now that I'm not saying it would be easy! On the contrary it is very hard but it should be (at least) theoretically possible without any fancy gravity assist or ion + solar panel tricks.

 

Now I think this challenge is still impossible. That's because even if you achieve evrything I described above I haven't been able to think of a way that would allow you to land the kerbal safely without any input... The craft will just crash to the ground/ocean at terminal velocity. Using chutes is not an option because if you deploy them during the launch they will immediately open and you obviously can't fly to orbit then. If you don't open them during launch you can't open them at all since you can use no further input...

If you have any idea on how to solve this problem I would be very interested :)

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6 hours ago, tseitsei89 said:

But if you have any more ideas for the landing part please keep them coming :)

I've briefly entertained the idea of deployed parachutes in a service bay. It seems the parachute deploys visually, but does not create any drag, and does not get destroyed by aero forces. Not sure what it would do once in space. However, since the service bays are more resistant than honey badgers, burning it off during reentry would immediately tear the chute apart.

Lithobraking, on the other hand, is a very feasible alternative (I cannot believe I just said that). The crumple zone does compromise the aerodynamics a bit, though.

 

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13 minutes ago, Eidahlil said:

I've briefly entertained the idea of deployed parachutes in a service bay. It seems the parachute deploys visually, but does not create any drag, and does not get destroyed by aero forces. Not sure what it would do once in space. However, since the service bays are more resistant than honey badgers, burning it off during reentry would immediately tear the chute apart.

Lithobraking, on the other hand, is a very feasible alternative (I cannot believe I just said that). The crumple zone does compromise the aerodynamics a bit, though.

 

Nice! Now this is in theory doable but maybe too hard for anyone to achieve... :P

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16 minutes ago, tseitsei89 said:

Please explain why getting to orbit and doing a deorbit burn would be impossible in stock with no input after the launch?

What part did you not understand?
You're in orbit facing prograde. To de-orbit you'll have two options:
If your engine is still burning you will need flip your ship to face retrograde. Flipping your ship requires input. DISQUALIFIED!
With no engines burning wait half an a re-ignite your engine. DISQUALIFIED!
And for both situations you WILL need parachutes and you can not trigger those at launch for obvious reasons. An orbit to surface continuous suicide burn???? Not a snowballs chance in hell!
 

Edited by Tex_NL
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2 minutes ago, Tex_NL said:

What part did you not understand?
You're in orbit facing prograde. To de-orbit you'll have two options:
If your engine is still burning you will need flip your ship to face retrograde. Flipping your ship requires input. DISQUALIFIED!
With no engines burning wait half an a re-ignite your engine. DISQUALIFIED!
And for both situations you WILL need parachutes and you can not trigger those at launch for obvious reasons. An orbit to surface continuous suicide burn???? Not a snowballs chance in hell!
 

Sorry but did you actually read my post? I'll quote the relevant part for what you said:

Quote

4. You can't deorbit. Answer: You put some very low thrust engine on the front end of your craft pointing "the wrong way" that burns longer than your other engines. That way once you reach orbit your other engines stop but this one engine is still burning the opposite direction and will lower your Pe back to atmosphere if designed well enough.

And

Quote

Now I think this challenge is still impossible. That's because even if you achieve evrything I described above I haven't been able to think of a way that would allow you to land the kerbal safely without any input... The craft will just crash to the ground/ocean at terminal velocity. Using chutes is not an option because if you deploy them during the launch they will immediately open and you obviously can't fly to orbit then. If you don't open them during launch you can't open them at all since you can use no further input...

If you have any idea on how to solve this problem I would be very interested :)

 

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2 minutes ago, Tex_NL said:

Please go back to my first post in this thread and read it. I already said that.

Yes you did but then why did you say the opposite in your previous post?

Quote

You're in orbit facing prograde. To de-orbit you'll have two options:
If your engine is still burning you will need flip your ship to face retrograde. Flipping your ship requires input. DISQUALIFIED!
With no engines burning wait half an a re-ignite your engine. DISQUALIFIED!

There is also a 3rd option that you pointed out in your first post (and I pointed out in my long post). Now please tell me why this option is impossible. And please don't shout it makes you look angry.

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A few thoughts:

Staging (of sorts) is entirely possible using carefully timed explosive stack decoupling.

Lithobraking and orbit-to-surface suicide burns are individually impossible, but a suicide-burn-assisted lithobrake should be doable enough.

Using timed burnouts (due to fuel) and a changing COM should permit aerodynamic stabilization of the craft during re-entry and the suicide burn. You don't need a true suicide burn; you just need enough thrust to lower terminal velocity to something survivable.

Someone who isn't me should try each component individually as proof of concept.

Edited by sevenperforce
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