ideas: simplest orbiter and collision challenges

[inigma]

Was wondering if these have been challenged:

Simplest Orbiter:

The cheapest, fewest parts orbiter to successfully orbit a Kerbal with periap above 70k and return safely. Mainly for updating the design used for the How to Get into Orbit wiki tutorial I wrote.

Fastest Interceptor:

If China can do it, KSP can. Build the fastest interceptor to destroy a satellite orbiting at 100km.

Large Kerbol Collider:

Kerbal scientists have pushed for decades to build larger and larger colliders for the exploration of science. Now they want to take their experiments to space to see if by creating the fastest head-on collision by two nuclear engines one could induce a wormhole to the mythical Sol star system rumored to be on the other end of the galaxy. Can you record the fastest orbital collision between two manmade objects - preferably the above-mentioned nuclear devices?

[tavert]

You do realize you can get to orbit in only 3 parts, right? A command pod, an X200-32 fuel tank, and an LV-T30 will get to orbit in a single stage, and if you're a good pilot it will even have enough fuel left for powered landing back on Kerbin. You could go "cheaper" by using the X200-16 tank and an aerospike, but that's more difficult to control. For new players a parachute makes sense, obviously. And keep in mind the part costs right now make no sense and aren't even remotely balanced, they're merely placeholders.

As described in your tutorial, the manned version of your basic orbiter doesn't have enough delta-V to reach orbit, and the unmanned one will run out of electricity if you have the throttle off for a few minutes. You want a lighter engine for the second stage like the LV-909, the T30 is overkill and too heavy for a small upper stage.

Have you tried either of the other 2 things you propose? An in-space collision with high relative velocity is actually very difficult to pull off and more down to luck than skill, the stock game doesn't give you enough information or precision to do this in any reliable way without cheating the persistence files (see one of Scott Manley's videos, I forget which). You're also very likely to just pass through the other craft with no collision if the velocity is high.

Edited June 5, 2013 by tavert

[inigma]

I didnt think about using larger tanks, but if the challenge was just fewest parts at the cheapest it would be the x200 16 tank with command mod and aerospike as you suggest. Bravo. Are you able to achieve orbit to prove it?

The design I mention in the article is able to get into orbit. I've done it several times with fuel even to return. Highest circular is about 80km. You need the second LVT30 for its power to do it though. The smaller engine just doesn't cut it. So far its the cheapest design into orbit. I can even get the unmanned one up easier than the manned design. Try it.

And I know the collision challenge is tough. Thats why I want to offer it.

Edited June 5, 2013 by inigma

[Francesco]

stock, manned 1-seat SSTOs are even easier right now, with the new lander can: using a LV-T30, a 3200l fuel tank seems overkill, a 1600l one should be enough.

have to check this, brb.

[zarakon]

A little while ago a I used MechJeb to put a whole bunch of craft with wide surfaces areas into equal but opposite orbits to try to get collisions in a supercollider sort of way. Half went one way, half went the other, all equatorial at 100km.

What I found was the same issue that I've had when testing high-velocity projectile weapons, and that other people have had when trying to build Kerbal cannons. At high speeds, objects don't move on a continuous path, they just teleport from one point to the next in each time step. So even if you are able to get two craft to line up their orbits perfectly for a high-speed collision, it is very likely that they will just jump past each other and not register a collision.

[inigma]

So if you're going fast enough, you could timestep...er warp through objects without colliding with them? Sweet! I wonder if its possible then to move a craft fast enough in KSP to actually warp through a planet...

[duncan1297]

it is, I have done it several times

Edit: sorry i misread your question, I have done it with time warp.

[zarakon]

I have gone straight through Kerbin on high timewarp several times

[jwenting]

remember that for inexperienced pilots you have to factor in extra fuel as they're not experts in timing and planning everything to be optimal.

That's something the "pros" often forget, most players, especially the rookies like me aren't pros and will not be able to make it into orbit with the ultra lean craft you guys use.

Here's 2 craft files that can work:

http://www.hornet.demon.nl/KSP/Needle%201%20Light.craft (80km orbit quite achievable).

http://www.hornet.demon.nl/KSP/T4a.craft (this one has an unmanned probe, can go beyond LKO with that, so can likely be adopted for a 1 Kerbal capsule easily).

[3_bit]

Couldn't "Simple" mean easy-to-use? Otherwise I can make an orbiter in less than 8 parts with a probe and solar panel.

[inigma]

The unmanned version of the "cheapest" orbiter works well, with lots of fuel, and if one follows the wiki article's instructions, will get a total newb to orbit in the first few tries... well, maybe. It got me up there, and I'm a newb and had no idea what the blue ball thingy was for.

[tavert]

The design I mention in the article is able to get into orbit. I've done it several times with fuel even to return. Highest circular is about 80km. You need the second LVT30 for its power to do it though. The smaller engine just doesn't cut it. So far its the cheapest design into orbit. I can even get the unmanned one up easier than the manned design. Try it.

I did. I recreated the exact design you spelled out, the manned version only has 3962 m/s vacuum delta-V, it's not enough to reach orbit. You're sure the wiki page isn't missing another fuel tank? Not sure how to convince you I know what I'm talking about regarding the smaller engine. Here http://www.imgur.com/a/kcibi are some flights of the manned version of your design using MechJeb (so anyone can reproduce the same flight path), compared to the same design replacing the upper stage engine with an LV-909. No orbit vs orbit, either I'm missing something or you are. Failure is certainly still possible with the LV-909 design, but it appears to me that failure is guaranteed with the T30 in your manned design.

Also Francesco was right, the X200-16 is enough with a T30 and the 1-man lander can. Might be borderline about leaving enough fuel for return/landing though.

[inigma]

I did. I recreated the exact design you spelled out, the manned version only has 3962 m/s vacuum delta-V, it's not enough to reach orbit. You're sure the wiki page isn't missing another fuel tank? Not sure how to convince you I know what I'm talking about regarding the smaller engine. Here http://www.imgur.com/a/kcibi are some flights of the manned version of your design using MechJeb (so anyone can reproduce the same flight path), compared to the same design replacing the upper stage engine with an LV-909. No orbit vs orbit, either I'm missing something or you are. Failure is certainly still possible with the LV-909 design, but it appears to me that failure is guaranteed with the T30 in your manned design.

Also Francesco was right, the X200-16 is enough with a T30 and the 1-man lander can. Might be borderline about leaving enough fuel for return/landing though.

You are so totally right. My design had the LV-909 engine for the second stage. What a doht for me to insist otherwise. Sorry 'bout that. I corrected the wiki. I'm such a newb.

[tavert]

You are so totally right. My design had the LV-909 engine for the second stage. What a doht for me to insist otherwise. Sorry 'bout that. I corrected the wiki. I'm such a newb.

No worries, glad we sorted it out. Apologies if I came across as dickish in any way. Welcome, have fun, etc. If you can get an in-space collision to happen reliably we'd love to hear how.

[inigma]

Well I did it with your design. I got into space with an OKTO2, Rockomax X200-32 Fuel Tank, and LV-T45 Liquid Fuel Engine with more than enough fuel for a return. It's a three part orbital rocket. Not that hard to fly. I might include it in the Tutorial.

[sal_vager]

inigmatus, I'm going to move this to General so you and the guys can discuss your challenge ideas, flesh them out and help you work out how you are going to present them, then when you are ready you can make a new thread for your challenge later.

This is more a discussion then a challenge anyway