[WIP] Dreamer - SNC Dream Chaser - Download Available!

[artwhaley]

Crap - I just bundled the folder didn't I. I'll update the download in a few minutes. Thanks for pointing it out!

[artwhaley]

Fixed it! Sorry to anyone who didn't figure out how to correct my mistake!

[hieywiey]

Man, this thing is so capable. I use it to send my Kerbals to my munar station, I transfer and return on it's own power (I just completely fill up the tank). It has 4,273 m/s of ∆V, from what Kerbal Engineer says.

[artwhaley]

I'm glad you like it! I actually do want some opinions on how much Delta-V it should have available.

Late in the last round of development I dropped the mass of all of the parts to ridiculously low numbers... which made the delta V go WAY up. I think 4000m/s+ is a little too generous... and you're right, that's what it's got now. With the right engines it could practically SSTO, if you didn't mind circularizing with your RCS. And the real thing requires an Atlas V to get up there... so the delta-v, and the TWR are both going to drop in the final release.

I'd love to hear some feedback about what people would want to do with this thing? Realistically, Dream Chaser would probably only have enough delta V to circularize the orbit, rendezvous with a target that was already in the same plane, and deorbit. In Kerbal terms, that may be (generously) 700-1000 m/s? (If you're trying to play KSP realistically, like, doing math before you hit the space bar and stuff, it's probably even lower - maybe 200m/s to circularize, 100m/s to transfer then circularize in the target's orbit... 75 m/s to deorbit, and a 15% contingency for slight plane adjustments or other miscalculations?)

But I personally don't do a lot in KSP LKO. Hopefully someday contracts will expand and include satellite maintenance, crew service, etc - and then there will be a reason to have a cost effective and fun ship to circle the blue-and-green sphere in... but for the moment, most of the fun happens when you get further away from Kerbin.

What would make people actually use this more than once to try it out? It WILL be able to launch and recover Scansat and RemoteTech satellites, but what else would you do with a small shuttle like this in LKO?

I'm currently thinking that at least keeping it able to make the Mun transfer - perhaps with an srb assisted launcher rocket that leaves enough delta-v in the second stage to handle the Trans-Munar Injection so the Dreamer just has to be able to handle the course correction burn, capture burn and munar escape burn. Technically 700m/s would be plenty for that, but I'd probably round up to 1000.

To extend the ship further, perhaps I'd make a cargo bay module that replaced the payload with andother 1000m/s worth of fuel... as with 2000m/s it could make a Duna transfer and return, assuming you used aerobraking.

So the delta V budget for the whole family of parts would be something like -

Atlas V lower stage(CCB) - 2200 m/s , TWR of 2.5ish

Atlas V Upper Stage(Centaur - dual engine variant) - 2700 m/s, surface TWR of 1.2ish

Dreamer Vehicle - 1000 m/s, surface TWR around .5

Atlas V SRBs, where 2 of them add an additional 900 m/s to the first stage

Cargo-Bay-Fuel-Pack - 1000m/s added to Dreamer Vehicle system, allowing Duna transfer and return

Thoughts anyone?

[Ikaneko]

Your suggestions look good, but what is up with the animations on the cargo bays and the docking port. They seem to be unclosable. ;.;

What are you planning to change??

[montyben101]

Hmm I don't think it should be able to go to duna... Possibly the mun but duna is an overkill

[artwhaley]

Well, if that's the case, I'm planning to change that those animations can't be reversed... but I haven't had that problem. I'll check and make sure the colliders are animating in the way you'd expect... that's my first guess as to what's going wrong- that the part you'd need to click to tell them to close isn't in the same place as the part we're looking at.

As to what else is in the plans -

General bug-squashing.

I have begun to seriously balance lift and mass for atmospheric flight/control in vertical launch. I don't want the thing to fly TOO well - you shouldn't be able to fly cross country in it or take off from a runway, you should have to deorbit within 15 degrees or so of the right spot and have enough cross range capability to make adjustments from there on the way down. This is about 80% there, I think, unless changing something else drastically affects all of this and I start it over.

I plan an Atlas V launcher for it - the Centaur stage will be 2.5M sized so it can be used with other payloads. This isn't started yet. CluelessModeller had talked with me a little about his work - and he's abandoned his model in the abandoned .blend thread - though it's higher poly than I want. I'll either take a stab at decimating it, or load it as a reference object and model a low-poly Atlas on top of it... so I don't think this part will take that long. The engine details on the two stages will be the slowest parts to model there.

I plan a payload pack that includes some of the following -

KAS module with storage, a winch, and a pipe attachment - done... a little buggy...and a little bland on the texture... but working

Additional fuel tank for payload bay - already got a model that I can use for this - so done.

Universal storage module for the payload bay - a bit that users can add resource modules to to make it work with their preferred life-support or resource mods - model done.

Satellite deploying arm or bracket - waiting on the new IR multi-transform in single part plugin before I do too much here!

I haven't played too much with fitting a functional satellite in the payload bay - it does fit several well laid out .625 parts... but I may model a basic satellite that fits well with the bay/deployment arm and provide so users can add their own modules to it to make it work with their favorite satellite mods - remotetech, scansat, etc.

I want to make it FAR and NEAR and DRE compatible. I haven't done much with any of these systems, so this will be slow, but I think it's important to a lot of users so it will happen.

The release version will have a model of the body without the payload bay and without the nose-cone docking port, to offer a choice of a more 'real-world' version of Dream Chaser to go along with the fun-to-play-with 'game-ified' version in the development download.

I want to release it with a docking port part for use on stations that works just like the standard docking port but is a little 'longer' (as in, stands further out from the station) to make it easier to use the rear dock on Dreamer. It's possible to dock to most things right now, but those engines are in pretty tight proximity so you have to really think about your roll as you back towards something. I'd like to make a part that will make this a little easier.

Are there other things that other people want to see from it?

Art

[hieywiey]

I find that I can put two of the big 80 size KAS containers, but part of it clips through the cargo bay, also I have experimented with drag chutes using RealChutes (I practically have to have that mod cause it's awesome!) and it works pretty well, but I don't like that I always have fuel left over and that makes landing a bit of a challenge, so maybe a fuel dumping port part?

[Gristle]

...If I were going to build an arm for the payload bay to assist with recovery and launch of satellites... do people prefer Infernal Robotics or Lazor Systems as the engine behind it? I haven't looked into either, really, so I may find out that one is way easier to work with than the other... but it would be good to know what people are already using so if I can avoid making users download another plugin, I'd like to!

Have you seen the new plugin specifically for robotic arms that Sirkut is working on? http://forum.kerbalspaceprogram.com/threads/97269-WIP-Infernal-Robotics-Robotic-Arms

Maybe give Sirkut a shout and see if he's got something you could use.

[Odyssey]

Any chance I could get this on a smaller scale? I'd like to shrink this down so that the rear adapter fits on a 1.25 meter part (essentially the smaller standard fuel tank).

I tried tweaking the scaling options, but so far I haven't gotten it right (only worked on it about 10 minutes last night). I fly a lot of missions with the KSO and I wanted to scale this back a bit so that it wasn't almost the same size as KSO.

[montyben101]

I don't see why you would want it smaller. That would make the cargo bay useless

[kiwiak]

Although pteron shuttle looks nicer this much more playable and usefull.

[Odyssey]

I don't see why you would want it smaller. That would make the cargo bay useless

It would have the bay be useless, but I'm not a fan of the bay in the first place. The real DC doesn't have it and this one is already pretty small to begin with.

DC is mostly for ferrying astronauts. Any supplies it takes are stored inside, though they are minimal. It's not meant to be a payload launcher.

[artwhaley]

I don't really think making it smaller fits into my plan for it. If you want a smaller ship I'd point you towards the Pteron, or Whimchaser, which is a backburner project of mine, to make a 1.25m sized, quite kerbalized crew transport part. The real centaur stage is 3.0meters, so the fact that the Dreamer fits on a 2.5m upper stage means I'm already just little undersized from reality, which is where I think I want to stay for maximum playability/compatibility with other parts.

The cargo bay will be optional in the final release... I value playability over realism in the game... with a truly faithful model of Dreamchaser there isn't much to do other than launch it to LKO, rendezvous, and come home... and that flight plan is only fun a couple of times.

If you really want to fit it on a 1.25m launcher... this OUGHT to do it, but I haven't tested it. At the top of each cfg file there's a model tag, where I link to the correct .mu. Something like :

MODEL

{

model = AxialAerospace/Parts/dreamer/drmcabin

scale=1,1,1

}

If you change THAT scale number to scale=.5,.5,.5 it should correctly adjust all of the attach nodes and make everything just work. I have no idea if you'll have to fiddle with mass or lift parameters to make it still fly... but I'm guessing it should work well enough.

Art

[Odyssey]

If you really want to fit it on a 1.25m launcher... this OUGHT to do it, but I haven't tested it. At the top of each cfg file there's a model tag, where I link to the correct .mu. Something like :

MODEL

{

model = AxialAerospace/Parts/dreamer/drmcabin

scale=1,1,1

}

If you change THAT scale number to scale=.5,.5,.5 it should correctly adjust all of the attach nodes and make everything just work. I have no idea if you'll have to fiddle with mass or lift parameters to make it still fly... but I'm guessing it should work well enough.

Art

Cool, That was what I was looking for. To me, that seems like the right size, but the thing handles like it's got all it's weight in the back. The center of gravity means that the nose rises at the slightest provocation. Still looks awesome though

[hieywiey]

I just can't thank you enough for making this AWESOME mod! Also I kinda made a new signature which advertises this thread!

(Uses psychological powers to make you notice new signature)

[artwhaley]

Updated the first post. A new version is available on Kerbal Stuff.

The short version is -

The body comes with both options now - one with cargo bay, one without. There's also a version of the nose without docking port. It still opens, but my thought on this is that it's for use in the VAB only - stashing your mechjeb, protractor, additional batteries or RCS tanks... anything small that you don't want hanging off the side of the ship. Then in flight you can pretend it doesn't open.

There's a full Atlas V launcher included with the download. I'm going to make the .Blend file for this one available over on the abandoned .blend thread so hopefully someone will take it up and give it some more texture detail, and build some fairings for it to make it useful for other payloads besides the Dreamer.

The weights and flight parameters are mostly in balance now... for stock Aero. I'm really pretty stalled on getting it to work with FAR, as I just don't have the FAR experience with building planes from known working parts... so it's even harder to try to troubleshoot and balance the parts while I try to learn to build airplanes. I may come back to it eventually, but I'd REALLY love for someone with some FAR experience to look at it and give me advice in where to start.

It IS setup to work with DRE now!

I've included 3 of the 4 payload bay modules I have planned. There's an LFO tank, a generic resource container (it comes with TAC Life Support resources, but the idea is that people can edit it to hold whatever it is they want to haul.) and a single-part KAS piece that includes a container, pipe end-point, and winch.

Both docking ports seem to work now. It's hard to dock with extraordinarily light vessels, but I don't think that's a problem with my parts... as much as it is with KSP, right?

There's still a lot of flex in the interstage adapter between the CCB and the Centaur stage of the launcher. in the .craft file I attached to the download I ran four struts across this joint to stiffen it. If anybody has input on a better way to make this joint steadier, I'd love to hear it.

There's spare room in the Centaur Stage of the launcher. If you're trying to push the Dreamer to higher orbit you'll want to fill this on up, but it comes ready to get you to LKO. You'll also want to fill this tank up if you're adding the additional fuel module in the Dreamer cargo bay... as this fuel, of course, adds significant weight.

In the stock configuration it easily handles 100km orbit without dipping into the Dreamer's 1100m/s of Delta V at all. If you fill the Centaur all the way up it adds another 800m/s or so... ALMOST enough to complete a trans-munar injection with the centaur stage before you ditch it and finish the burn with the Dreamer's OMS engines. This leaves the Dreamer with more than enough dv to capture, rendezvous, and then return from the mun.

If you fill up the Centaur AND add the cargo bay tank... you can JUST BARELY make it to Duna's orbit and back... if you aerocapture and don't screw up anywhere and waste fuel. There's not a LOT of wiggle room. But it's a fun challenge. With the mass and drag of the Dreamer I had to aerocapture LOW the one time I tested this... around 8500m.

Anyway. Please commence bug reports and pointing out anything that looks or works stupid... after you stare at something for a month or two you stop seeing the details yourself, so do point out anything you see.

- - - Updated - - -

I just can't thank you enough for making this AWESOME mod! Also I kinda made a new signature which advertises this thread!

(Uses psychological powers to make you notice new signature)

Thank you so much!

[montyben101]

:0 .... looks so good!!!!

[artwhaley]

The link to the .blend for my AtlaV launcher is here - if anyone is looking for a project. A couple of days spent on the texture and putting together a set of Atlas V fairings and it could be a cool standalone mod pack.

https://www.dropbox.com/s/otg068p8nbhqb82/AtlasV.zip?dl=0

[artwhaley]

I've started work on the IVA...

Mostly using the Alcor props because there's awesome.

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[Helix935]

I've started work on the IVA...

Mostly using the Alcor props because there's awesome.

http://imgur.com/a/VA8uh

now that sir is a nice IVA. Keep it up

[Dr. Jet]

What is really interesting - is how this birdy behave in FAR/NEAR physic model. Pteron for example was still unable to defeat CoL bug when I saw it last time.

[01010101lzy]

I'm wondering if this thing supports FAR and DRE.............

[artwhaley]

It's fully DRE-ready. Far... well... I haven't tested it since I built the launcher.

When I tested it before with stock launch vehicles, the ship itself sort of could fly... it was hard, but possible. but I couldn't launch it on a rocket, because all of the wing lift was dragging the CP WAY forward. With the longer launch vehicle with higher engine gimbal allowances, it might just work now. The engine plate of the ccb on the launcher is a separate part, so specifying a forced drag profile for it might 'hackily' make the thing stable. The real Atlas gets away without fins because it has very good active guidance.... which KSP doesn't necessarily simulate well.

To be honest, FAR is way down my priority list, because I don't play with it. So when I DO get around to adding support for it, I'm expecting to have to lose a week learning to build spaceplanes for FAR using stock spaceplane parts... THEN hopefully I'll be able to translate what I've learned to configuring my parts to work. I just sort of keep hoping someone will volunteer to do that part. I'll eventually get to it... but right now I'm working on bug squashing and getting the IVA ready.

[Ikaneko]

This...

Now this has come on!!

You are one talented modder!!

I have one question though: when is that kerbal module going to be added (i'm not sure you even said that there will be one. If not, consider this a suggestion!!)??

How many kerbals will it hold (if you haven't mentioned this ever, I suggest 4).