Karman Crossing Challenge (Stock or mod)

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@Andetch K-Prize thread? I'm afraid I'm unfamiliar lol.

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9 hours ago, Lisias said:

But I like @neistridlar approach to promote efficiency. It will prevent a "moar boosters" :-) approach to get high escores (exactly what that mastodon of mine did), what hoioh's approach ignores. But it doesn't promote accuracy (landing on airstrip - or on a Pad as I did).

So the multiply by the score 1.5 if landed on a runway does not promote accuracy? As for measuring the time above the Karman line, two screenshots should be sufficient, one when crossing on the way up, and one when crossing on the way down. The difference in MET would be the time above the karman line.

2 hours ago, Bitrefresh said:

@Andetch K-Prize thread? I'm afraid I'm unfamiliar lol.

Not entirely sure if you are joking or not, but anyways here is the thread:

I need to get around to making my own entry here soon.

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9 hours ago, Lisias said:

Not one of my brightest moments... =/

How much fuel it had at takeoff, and how much it had at touchdown? Some scores take this in consideration. (and I couldn't take the numbers from the video, Youtube shadows that part of the video, !#\$#!#@\$)

200lf on take off and 57.07lf on landing

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15 hours ago, Lisias said:

I think that the time you spend above Karman line should be considered.

Might have been mentioned, but that is just a function of altitude.   Given these are all basically straight up and down trajectories, the altitude is determined by velocity when crossing the Karman line, which has a time element already considered.

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Just now, Gargamel said:

Given these are all basically straight up and down trajectories,

But they don't have to be and not all "up and down trajectories" are equal because some are a bit more "up and down" than others causing differences in time spent above the line. Besides, we're attempting to promote staying up there for longer, thus we need to find a way to do so

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2 minutes ago, hoioh said:

But they don't have to be and not all "up and down trajectories" are equal because some are a bit more "up and down" than others causing differences in time spent above the line. Besides, we're attempting to promote staying up there for longer, thus we need to find a way to do so

Hmmm... Fair nuff.   But you'll need a timer.  Maybe getting some of the smart parts, reducing the mass to 0 (and not counting against the score), and having it trigger something at 70k on ascent and descent so it shows up in the log.

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When I created this as a challenge, I liked the idea of scoring on the amount of time spent above the Karman line but had no idea on how to measure it.

In terms of the amount of time spent above the line being directly correlated to height - I am not so sure. When I use things like my Caveman Tech SSTO, the AP is usually below 71,000 (or you don't have enough fuel to circularize), however it spends ages between 70km and the AP as the ascent angle is usually around 1 - 2 degrees. It also can keep getting lift from the wings up to around 60 - 65 km (so you can actually raise the AP to above 70km without use of the engine once you're going fast enough).

The point of this explanation is not to say how brilliant I am for making a Caveman Tech SSTO (but I do feel  rather chuffed with the achievement) but more to show how you can get above the line without going straight up. For example, if you can get your plane up to around 25,km then accelerate to above 2,500m/s at a near horizontal AoA, you will probably cross the Karman line. Yeah, heating then becomes an issue, but it is a different way to get up there.

I am also really appreciative of the efforts put in by people to get a good scoring equation - I would prefer a communal decision on how to score this properly rather than myself making a despotic decision.

Also, for anyone wanting to do multiple entries - I have no issues with putting multiple scores up next to your name.

Edited by Andetch
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2 minutes ago, Andetch said:

2,500m/s at a near horizontal AoA

This, however, is not possible with airbreathing engines alone. You will top out at 1680m/s with a Rapier and around 1320m/s with the RAM jet, so if we're not using any oxidizer those are the highest speeds you could possibly achieve at around 26km

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6 minutes ago, hoioh said:

This, however, is not possible with airbreathing engines alone. You will top out at 1680m/s with a Rapier and around 1320m/s with the RAM jet, so if we're not using any oxidizer those are the highest speeds you could possibly achieve at around 26km

No-one got any idea's on how to get them to go faster? Or good enough to adjust angles so it works from 1,680m/s?

Edited by Andetch

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I don't think so, they've been designed to lose thrust when they get to a certain speed, so I doubt it's even possible.

And because the atmosphere is very thin up there I wouldn't think you could change the angle and maintain those speeds, you'll have to build something that can reach such a speed at such an angle that you can follow pro-grade and kick it out of the atmosphere at said angle. But I'm not sure it will give you any benefit because you'll have to come back to the runway, which will be a long way away

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1 hour ago, Andetch said:

No-one got any idea's on how to get them to go faster? Or good enough to adjust angles so it works from 1,680m/s?

21 minutes ago, hoioh said:

I don't think so, they've been designed to lose thrust when they get to a certain speed, so I doubt it's even possible.

And because the atmosphere is very thin up there I wouldn't think you could change the angle and maintain those speeds, you'll have to build something that can reach such a speed at such an angle that you can follow pro-grade and kick it out of the atmosphere at said angle. But I'm not sure it will give you any benefit because you'll have to come back to the runway, which will be a long way away

It seems to me the thrust cutoff is based on mach number, not speed, as I have been able to push the rapier up to 1710m/s sustained flight around 19km (however my nosecone overheated), but regardless it is not much faster. I might do some testing with my craft to see if I can get a better time above the karman line with a more horizontal trajectory, as I know that it is entirely capable of much more horizontal trajectories (it took a few tries to get it vertical, as I'm doing most of the accelerating at low altitude, then doing and insane G turn while continuing to accelerate). Getting back to the runway becomes harder of course, but at least with my design, I am basically able to reenter, turn around and jump almost all the way back it to space again, so it is doable.

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Ok, the results are in. All attempts reached a max speed of 1570-1600m/s on the ascent, and nearly burnt to a crisp, So I don't think I could have pushed them much further without completely changing my ascent strategy. The highest was 202km with 436 seconds, the lowest was 117km with 291 seconds, and everything in-between was in-between. So it seems that going straight up is simply the better strategy for maximizing the in space experience.

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So straight up and turn left it is then? Lol

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23 hours ago, Andetch said:

Can definitely try and get a nice scoring where you get a penalty for building too small....

That would help my entry.

Edited by a_space_oddity

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6 hours ago, Gargamel said:

Might have been mentioned, but that is just a function of altitude.   Given these are all basically straight up and down trajectories, the altitude is determined by velocity when crossing the Karman line, which has a time element already considered.

Yeah, some empirical testing here demonstrated exactly what you said. Without thrust and without atmosphere, we are essentially doing ballistics here, on a parabolic launching (literal translating for a entry from my local high school books). Incredible how you miss simple things as you get old. =D

All that matters is the vertical speed at the moment you loose thrust.

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6 hours ago, Andetch said:

No-one got any idea's on how to get them to go faster? Or good enough to adjust angles so it works from 1,680m/s?

As opportunely reminded by @Gargamel , all that matters is vertical velocity. On spacecrafts, if you get enough horizontal velocity, you ended up with vertical velocity too (it`s exactly what we do to launch into space by the way - speeding up horizontal velocity until we get enough centripetal force to countermeasure the gravity), but getting into there while on atmosphere will burn you to ashes.

It`s the reason, until now, that small ballistic vessels have an edge - we`re converting all our thrust into vertical speed, what can only be accomplished on light vessels with huge TWR.

Some testings here suggests that weighing crew number over altitude counter measure this. And by somehow promoting a better crew/vessel_cost ratio into scoring, one have to build a really fantastic small vessel (and landing it on a pad, if using my scoring) in order to have a chance against a high crewed vessels.

4 hours ago, neistridlar said:

The highest was 202km with 436 seconds, the lowest was 117km with 291 seconds

202Km high is an achievement. My best until the moment is about 160km. :-)

Edited by Lisias
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How KSP handles inertia? I'm getting the grasp on drag, but I'm didn't make my mind yet about inertia...

edit: Whoops... wrong window. sorry.

Edited by Lisias

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While looking on the numbers from the spreadsheet (this one, now under ownership of the Challenge Master, and this other I'm messing around), we came to the conclusion that would be very hard (and probably frustrating) trying a "one rule to score them all" approach.

How about, then, just open 4 or 5 "awards", each one being ruled by its own formula, and then every vessel would be scored on each one of them? And then the "award" would be granted for the bests scores in each formula. Would be *very* interesting to see a given vessel being awarded in more than one formula! (that would be a challenge by itself!).

The following is what we came until the moment (just brainstorming! Please develop the concepts!):

1. The highest altitude (bonus for each original part that touch down with the root part?)
2. The best altitute/crew ratio (which bonus would be nice?)
3. The best altitude*cost/crew ratio (ditto)
4. The biggest crew to cross the Karman/altitude ratio (ditto²)
5. The best crew/max_horizontal_velocity ratio (ditto³)

Contests for relaunching the vessels and landing them on pads can be interesting also! I would love to see a 50 crew vessel landing on the VAB helipad! :-D

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Addendum: I think it would be a good idea to award stock and mod vessels separately.

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My first attempt:

(4) stock parts ..... \$8,432 ..... 113,321m ..... (1) bounce ..... (1) crash

Imgur Album:  https://imgur.com/a/zuHLV

Edit: Apparently this is a common strategy.  =\

I'll try something else.

Edited by Fett2oo5

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Second attempt:

(5) stock parts ..... \$8,832 ..... 108,847m ..... (1) "Landing"

If the engine hadn't have broken off and rolled down the hill, I would have scored:  .405

Imgur Album:  https://imgur.com/a/o3YB7

Edit: Apparently this is a common strategy.  =\

I'll try something else.

Edited by Fett2oo5

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16 minutes ago, Fett2oo5 said:

Edit: Apparently this is a common strategy.  =\

For while. :-)

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6 hours ago, Lisias said:

-snip-

The following is what we came until the moment (just brainstorming! Please develop the concepts!):

1. The highest altitude (bonus for each original part that touch down with the root part?)
2. The best altitute/crew ratio (which bonus would be nice?)
3. The best altitude*cost/crew ratio (ditto)
4. The biggest crew to cross the Karman/altitude ratio (ditto²)
5. The best crew/max_horizontal_velocity ratio (ditto³)

Contests for relaunching the vessels and landing them on pads can be interesting also! I would love to see a 50 crew vessel landing on the VAB helipad! :-D

I like the Idea of having multiple rewards to stretch for, and keep a leaderborad for. Here are my comments on the score proposals (assuming bigger is better).

1. This one is obvious and good.
2. So basically go as high as possible with as little crew as possible? This one seems a bit odd, maybe altitude*crew would make more sense?
3. Make the most expensive craft with as low a crew capacity as possible and bring it as high as possible? Maybe altitude*crew/cost makes more sense?
4. Bring as many kerbals as low as possible above the Karman line? Maybe just the biggest crew to pass the Karman line would be better?
5. Bring as many crew as possible as straight up as possible? maybe crew*max_horizontal_velocity makes more sense?

As for precision landing bonuses, maybe ad multipliers, like 1.4 times bonus for landing on runway, 2 times bonus for landing on the roof of a building, etc. Or maybe something like the K-prize or STS challenge. That is you get the same score, but with additional clauses added to the reward.

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I think we're definitely moving in the right direction.. A multi score system would be better I think - then craft like mine that can cross the Karman line multiple times and carry more people have some relevance, rather than just a pod on an engine winning it all as we are seeing come up many times now...

What I want to do is find a way of eliminating anomalous results, and understanding what caused them, and if we can make it a "class"

@Fett2oo5 welcome to challenge! Nice attempt! Did you self score yet?

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I've been following everything with the scoring and think there is an option left open:

Simply make several leaderboards for each achievement like so:
1. Most kerbals over the Karman line (just go big, or go home)
2. Furthest over the Karman line (a simple "who can get the highest" objective, currently at 202km-70km = 132km as per Neistridlar, unconfirmed though)
3. Lowest price per Kerbal over the line (for economic reasons and accessibility ofcourse, after all, who wouldn't want to visit space for a couple minutes?)
4. Most "space-kerbal-km" (Multiply the max distance above the Karman line with the amount of passengers aboard, getting the most bang)
5. Lowest cost per "space-kerbal-km" (The most "bang for your buck" because if we're paying to go to space we want to get the most out of it!)

You could say it is mandatory to land on the runway (cause passengers don't like having to be picked up at sea) and give special commendations for extreme precision landings (such as on the helipad on top of the admin building) at your own discretion (maybe just an extra STAR or somesuch).

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