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One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics).

Posted By: Paul Rix

One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/20/12 01:56 PM

Some of you will be aware of the indie game Kerbal Space Program produced by 'The Squad'.

Kerbal Space Program in it's present state is essentially a sandbox physics game where you build your own rockets and launch them into space. The action takes place on the fictional world of Kerbin, a planet smaller than Earth with one Moon (called the Mun). The planet Kerbin is populated by the Kerbals (little green men who want to explore space and visit the Mun.

Ok, enough of the storyline. Under the cute cartoon exterior KSP is like a light version of Orbiter that the rest of us mere mortals can understand and enjoy. You still have to learn a bit about orbital mechanics, but it is all presented in such simple terms that it becomes very straight forward and easy to comprehend. The KSP community is very active and there is a large amount of player produced content that you can download freely, from rocket parts to auto-pilot modules etc etc.

So, to get to the Mun you have to first design a spacecraft to get you there. The vanilla parts provided will certainly get you there, or you can add some very well done parts to provide some extra 'bling' (such as larger fuel tanks, payload fairings, crew capsules, lunar lander parts, bigger parachutes for landing amongst others). You assemble your rocket in the VAB (Vehicle Assembly Building), starting with the crew module and then adding stages from the top to the bottom. So the build sequence goes backwards from that of the mission (ie think about landing the capsule first, then add stages for the other parts of the mission until you have your final 'stack'. While putting the rocket together you can adjust the stage sequence using an intuitive drag and drop process. In flight, you cycle through the stages using the Spacebar.

After all the design and preparation, it is time to fly your creation. I put together a rocket using vanilla parts, with the exception of a player created autopilot module (called the Mech-Jeb if you want to download it).

It is going to be a night launch and we are going to the Mun. To add to the challenge, we are going to touch down at the same site as some of my previous missions (think of it as the site of a new moonbase).

So here we are, sat on the launch pad, Kerbals strapped in, and the autopilot activated for a vertical climb (pitch 90):


10, 9, yeah yeah, lets go!


We have cleared the pad!


As we leave the denser part of the lower atmosphere we can start to pitch over to gain orbital velocity:


The first stage is out of fuel, so it is time to get rid of it. You can see the RCS jets keeping the vehicle pointed in the right direction.


With the first stage gone, we continue to accelerate. Need to reach an orbital velocity of about 2300 m/s to achieve a stable orbit at this altitude:


This is the 'map' view. We can see our orbital path (the green line) and the spacecraft position (the capsule icon). Also notice all the space junk, spent stages jettisoned during previous launches. Space junk continues to orbit indefinitely or until the orbit decays and the part returns to the planet.


Starting the TLI burn to slingshot our intrepid Kerbalnauts out towards the Mun's orbit.


The second stage is out of fuel, so here we see the puffs of smoke from explosive bolts of the decoupler.


Using the map view, we can see that our orbit now takes us out to intercept that of the Moon. We have to lead the moon and aim for the point it will be when we get there.


The planet Kerbin is looking pretty small in the rearview mirror!


We are now getting close to the Moon (Mun)..


Captured by the Moon's (Mun's) gravity. Our lunar orbit is far from circular, so we can anticipate having to perfrom a retrograde burn to slow down when we are close to the Periapsis (lowest point of the orbit). That will result in a more circular orbit, close to the lunar surface (I usually aim for about 10-20 km).


Much better. You can see that we are now established in a fairly circular orbit and I have adjusted it so that our flightpath takes us over our target landing site (the capsule icon on the right side of the moon. You can also see a space junk icon, which is a rocket stage I jettisoned on a previous mission. I think it is going to be in orbit for a long time!:











Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 02:15 PM

So, it is time to tackle landing. Setting down in the target area is a simple case of slowing down at the appropriate time (now that flight path has been adjusted to fly over the landing site).
First we cut loose the spent 3rd stage:


Ans now it's time to slow down, ideally almost to a complete stop over the landing area. Here we are in a retrograde burn to achieve this:


Looking good, I pitch the craft to the vertical and unfold the landing legs..


Dropping down towards the landing site. We can see the labels for the previously landed craft:


Steady as she goes:


A successful landing! You can see that I have been experimenting with different designs. The smallest ship there was tricky to land because the descent stage ran out of fuel before touchdown, so I had to cut it loose and carefully land the return stage (not a realistic decision I know).




Time to head for home. The descent stage stays on the surface...








So now we are back in Lunar orbit. We now need to slingshot ourselves home..



Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 02:34 PM

While orbiting on the far side of the moon, I start a pro-grade burn to push the orbit out towards the Planet Kerbin. Again, we aim for an offset point because the Moon will drag us along while we are still under it's gravitational hold.


As the Planet's gravity takes hold we are now in a wide orbit. We will have to perform another retrograde burn to slow down and bring our flightpath close to the planet..


With the retro-grade burn completed, we can now see that the lowest point of the orbit brings us very close to the surface of the planet (in fact I brought it low enough that we will be able to use the atmosphere for aerodynamic braking).


Some time later, we are descending towards the planet at high velocity.


Time to lose the service module...




For now, we don't have to worry about burning up in the atmosphere, but that feature will be added at some point in the future.


Deploy the chute!


Thankfully we have a good chute!


Splashdown!


Now where's the helicopter, aircraft carrier and band? Oh well, such is the life of a Kerbalnaut
duh

Thanks for tagging along on my little adventure..
Posted By: ForSquirrels

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 02:45 PM

Looks cool. May have to check that out.
Posted By: Gopher

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 03:23 PM

That's pretty sweet, Paul. I remember playing an earlier stock version without landing legs and got pretty close to a moon landing, only to have too much lateral velocity on touchdown - you can guess the rest.
The persistence of objects is pretty sweet. Are the telemetry windows on the right hand side a new addition to 0.14?
Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 04:06 PM

Gopher, the game has come along in leaps and bounds recently. The telemetry data is part of the "Mech-Jeb" autopilot module, which is a player created addon (free).

For $15 KSP is great value and it is only going to get better. I have spent more time playing around with this than I have with many of my full price games.
Posted By: RSColonel_131st

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 05:08 PM

Cool game, well written AAR!
Posted By: Heretic

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 09:16 PM

Note: .13.3 will remain freeware, so there's no risk in trying out some of the cool stuff of the later versions.

One of my designs (user-made parts pack) from pre-Mun days:
http://i51.tinypic.com/1042cyw.jpg
Too bad .14 doesn't run on my laptop, otherwise I'd have already bought the game.


Anyway, good tutorial AAR. Gotta love the implemented persistent world!
Posted By: Panther

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 10:10 PM

I have lost many Kerbalnauts in my journey to the Mun. Great AAR.
Posted By: xclusiv8

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/20/12 10:20 PM

More of this plz =) This looks like so much fun. I might buy it when it gets released =)
Posted By: BeachAV8R

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. - 03/21/12 04:28 AM

That is really cool...
Posted By: Legend

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/21/12 04:46 AM

Great AAR, Paul! I've also played this one a bit when it first came out, didn't know it was this advanced already.

Originally Posted By: Paul Rix
So now we are back in Lunar orbit. We now need to slingshot ourselves home..


Shouldn't that be 'loonar' orbit?
Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/21/12 10:40 AM

Glad you all enjoyed the AAR, it was fun to put it together.
Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/21/12 09:19 PM

This was an interesting challenge, made possible with another player produced module called the 'RinComp'..

Orbital Rendezvous cool

Posted By: JoeyJoJo

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/21/12 09:59 PM

very cool Paul! I've been messing around a bit; but still have problems maintaining orbits; so I just try to build the biggest damn rocket I can and "shoot for the moon" lol...yes I realize this is impossible but I like things blowing up hehe
Posted By: purolator

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/22/12 08:18 AM

Thanks for the AAR and the screenshots, there certainly has been a lot of development since I tried it the last time.

But looking at your screenshots - where the heck are Jeb, Bill and Bob?

I'd especially miss Jebs character, this always happy madman - the more parts came flying the happier he became.
Posted By: Heretic

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/22/12 02:41 PM

Originally Posted By: purolator
I'd especially miss Jebs character, this always happy madman - the more parts came flying the happier he became.


http://i.imgur.com/vQtbG.png
Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/22/12 03:13 PM

hahaha

I think Jebediah is still in the mix, but they had to recruit more Kerbalnauts now that we can have multiple spacecraft active at any one time.
Posted By: bogusheadbox

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/22/12 08:45 PM

Gotto say. It looks brilliant and i really like the persistant items in space.

Looking into this.
Posted By: bogusheadbox

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/28/12 10:23 PM

Well, i have been playing with the stock version (freeware) and, i like it. Though Orbiter is more sim like, i like the ability to build your own rocket in many mad designs and impractical shapes and use of rocket power.

Just love it.

Sorry Kerbonauts - I have just purchased! Getting to the moon is not the hard bit for me. Its keeping that damned rocket together lol.

Many thanks for the heads up.
Posted By: FlyingMonkey

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/29/12 02:39 AM

This AAR made me have a look at the KSP demo, which I loved and then proceeded to buy it. I've landed on the Mun twice now, looking forward to docking, reaching other planets and all the nice features that are going to be added smile
Posted By: EinsteinEP

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/29/12 05:23 AM

Looks like a fun little game! Are there tools for helping perform orbital maneuvers, like plane changes or rendezvous, or is it all trial and error? e.g., do you really have to guess how much to lead the Mun when doing a TMI (Trans-Mun Insertion, hyuk) burn or can you determine it ahead of time?

I noticed the Smart A.S.S. control panel icons look just like Oribter's. I wonder if that's a direct steal, or if there's a common ancestor?
Posted By: snipey

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/29/12 02:20 PM

there are mods to help with orbit maneuvers, that smart ass panel is a mod for example and the newwest version includes an autopilot that will get you into an orbit and can land you. but the standard game is tial and error, but a handy trick for leading the mun is to start you burn when the moon rises
Posted By: Paul Rix

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/30/12 08:56 AM

It is great to see people here trying out KSP (and even buying it). As Snipey mentioned, there is a lot of trial and error involved with the vanilla version, but add a couple of small (and free) auto-pilot mods and you can launch into very precise orbits. There are also various tools available, developed by players, to assist with orbital calculations. Personally I find the map screen, which shows your projected orbital path, to be a very useful and intuitive 'instrument' in itself.

They just released v.14.2 which amongst other things, has a much nicer terrain engine. I haven't been able to test it myself yet as I am out on the road right now (one day I will treat myself to a decent gaming laptop).
Posted By: snipey

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/30/12 02:31 PM

they have already updated to 14.3 to remove some funny bugs like a space center at the mun, and unfortunately addid the mechjeb makes my pc lag too much.
Posted By: EinsteinEP

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/31/12 05:47 AM

For those of you that like the "why?", "how?", and "show me the math" of things, this little book is a gem. It walks you through the fundamentals of astronavigation at an introductory level, including orbital calcs, plane changes, rendezvous(es?), interplanetary transfers, etc. If you're not strong in math, don't worry - it walks you through most of it and puts nice little boxes around the answer equations for you. The text is also quite descriptive of the dynamics and physics behind the phenomena of orbital mechanics. I find it a very handy tool in Orbiter to calc my own orbits and maneuvers. Since KSP doesn't require you to bring a slipstick and current ephemeris almanac on each trip, you don't necessarily need this book, but it does explain a whole heck of a lot.
Posted By: bogusheadbox

Re: One small step for a Kerbal, a giant leap for Kerbal Kind. (Lots of pics). - 03/31/12 07:01 PM

Originally Posted By: snipey
they have already updated to 14.3 to remove some funny bugs like a space center at the mun, and unfortunately addid the mechjeb makes my pc lag too much.


Unfortunately i can't update to 14.3. Updater stalls at 99.4%. I see they are migrating their forums to a new server, maybe that has something to do with it?
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