Jump to content

[1.2] Shuttle Payload Technologies v0.2 - Spacelab Released!


MrMeeb

Recommended Posts

1 hour ago, White Owl said:

I'll note the craft file that comes bundled with this mod looks fantastic, but the CoM is waaaay too far aft. The real Orbiter's CoM in both the on-orbit and landing configurations was located near the center of the payload bay. That's so payloads of various weights wouldn't adversely affect the Orbiter's handling. No wonder people are posting about not being able to fly the thing... looks like the CoM is actually behind the main landing gear, so you couldn't even land it anyway.

The SSMEs from DIRECT are way too heavy, too. They're heavier than the real things, installed in an Orbiter that's smaller and lighter than the real thing. That's definitely a major contributor to the overall CoM problem.

I've watched lots of people using ore tanks to bring the CoM forward, to essentially increase the mass of the nose piece, but allows more control of balance. My only concern is the resulting imbalance with CoL, which is still fairly far back. I'll test it when I get back 

21 minutes ago, Doc Shaftoe said:

MrMeeb I wanted to thank you for putting out a fantastic addition to KSP. Your payload bay coupled with Pak's parts really make shuttles in KSP shine.

Thank you! :D

Link to comment
Share on other sites

13 hours ago, Z3R0_0NL1N3 said:

I've got a small suggestion. Could you include nodes on the payload bay for the MMU and the fuel cells that place them in the most accurate position to the real shuttle?

Double post because I missed you out!

Tl;dr: no

I'd rather not do that, because it'd take away from the flexibility of the bay. In my personal saves I use a set of 'hard points' (cubic octags) to provide nodes and then use predesigned sub assemblies that're intended to be compatible with certain hard points. It's hard to explain, and I can't get any pictures right now, so yeah. But I'd recommend you try that. 

Also, a quick google I did at a previous point yielded few results as to where and how many fuel cells the shuttle had, so even if I wanted to I couldn't 

 

Link to comment
Share on other sites

On 8/21/2016 at 0:50 AM, White Owl said:

I'll note the craft file that comes bundled with this mod looks fantastic, but the CoM is waaaay too far aft. The real Orbiter's CoM in both the on-orbit and landing configurations was located near the center of the payload bay. That's so payloads of various weights wouldn't adversely affect the Orbiter's handling. No wonder people are posting about not being able to fly the thing... looks like the CoM is actually behind the main landing gear, so you couldn't even land it anyway.

The SSMEs from DIRECT are way too heavy, too. They're heavier than the real things, installed in an Orbiter that's smaller and lighter than the real thing. That's definitely a major contributor to the overall CoM problem.

I use the stock SSMEs. Aren't those the same weight? Either way, I still can't fly the shuttle. Once it's gliding, it becomes either uncontrollable and tumbles, or it hardly glides, and more falls like a rock. I don't know how much MrMeeb can fix this. Does anyone have experience of the shuttle working better in FAR?

Edited by Z3R0_0NL1N3
Link to comment
Share on other sites

The only way I've managed to maintain stability from re-entry to landing (altho this is in a 4x scale kerbol system) is by using an angled probe core in the back at about 20-30 degrees locked to prograde, making sure plenty of RCS is left and not touching the controls except to help nudge back towards prograde if needed until velocity is down to about 500 m/s, then switch control to cockpit and pitch down sharply, then carefully, using prograde snap to stay close to prograde, as if I don't I will enter a flat spin, and slowly bring the shuttle to horizontal for landing. This doesn't even really work half the time though.

Link to comment
Share on other sites

2 hours ago, Z3R0_0NL1N3 said:

I use the stock SSMEs. Aren't those the same weight? Either way, I still can't fly the shuttle. Once it's gliding, it becomes either uncontrollable and tumbles, or it hardly glides, and more falls like a rock. I don't know how much MrMeeb can fix this. Does anyone have experience of the shuttle working better in FAR?

After doing a little bit of research, I'm learning that figuring out the total mass of a SSME isn't so simple, and I may have to eat some words. Some sources include only the bare engine, at a mass as low as 3392kg. Some sources include the engine controller, gimbal system, installation hardware, plumbing, etc. for a mass as high as 4957kg.

For our KSP purposes, and specifically for use with Cormorant and this mod, I'd argue that all the propellant plumbing should be included with the aft fuselage part that attaches to the payload bay. My reference book claims all that plumbing weighed 759kg per engine, so that leaves us with a mass of 4198kg per engine. However, that's 4.2t for a full-scale engine, which is some uncertain amount larger than a Kerbal engine.

Now I'm pondering how to solve this problem. Guesswork flat-out ain't going to work with a glider this perilously close to not gliding at all!

One approach occurs to me. I found documentation for the real orbiter's CG limits, both forward and aft. Known as CoM to KSP players; same thing. The real orbiter's total mass is known. The mass and location of the engines is known. I can therefore find exactly what the total mass and CoM of a real orbiter without engines would be. Next step would be to edit the mass of all our KSP orbiter parts until the CoM without engines is in the same place. That done, find the KSP orbiter's empty weight and compare to the real thing. Find what percentage of the real orbiter's total mass is accounted for by the engines. Edit the KSP SSMEs to the proportional mass. Edit the KSP SSMEs to the proportional thrust, to keep the same TWR.

Of course, all the same steps would be needed for the OMS engines too.

Once that's all done, the lift on all lifting surfaces will probably need tweaked to get the plane to fly right in stock aero. In theory, FAR's voxels should work as soon as we get the CoM right.

Well I know what I'm going to be doing today!

Link to comment
Share on other sites

4 hours ago, White Owl said:

After doing a little bit of research, I'm learning that figuring out the total mass of a SSME isn't so simple, and I may have to eat some words. Some sources include only the bare engine, at a mass as low as 3392kg. Some sources include the engine controller, gimbal system, installation hardware, plumbing, etc. for a mass as high as 4957kg.

For our KSP purposes, and specifically for use with Cormorant and this mod, I'd argue that all the propellant plumbing should be included with the aft fuselage part that attaches to the payload bay. My reference book claims all that plumbing weighed 759kg per engine, so that leaves us with a mass of 4198kg per engine. However, that's 4.2t for a full-scale engine, which is some uncertain amount larger than a Kerbal engine.

Now I'm pondering how to solve this problem. Guesswork flat-out ain't going to work with a glider this perilously close to not gliding at all!

One approach occurs to me. I found documentation for the real orbiter's CG limits, both forward and aft. Known as CoM to KSP players; same thing. The real orbiter's total mass is known. The mass and location of the engines is known. I can therefore find exactly what the total mass and CoM of a real orbiter without engines would be. Next step would be to edit the mass of all our KSP orbiter parts until the CoM without engines is in the same place. That done, find the KSP orbiter's empty weight and compare to the real thing. Find what percentage of the real orbiter's total mass is accounted for by the engines. Edit the KSP SSMEs to the proportional mass. Edit the KSP SSMEs to the proportional thrust, to keep the same TWR.

Of course, all the same steps would be needed for the OMS engines too.

Once that's all done, the lift on all lifting surfaces will probably need tweaked to get the plane to fly right in stock aero. In theory, FAR's voxels should work as soon as we get the CoM right.

Well I know what I'm going to be doing today!

I'd be very interested to hear what you find, and would massively appreciate any help balancing the shuttle parts to make it fly that bit better. I'm going to also ping @Pak, because I'm sure he will also want to be a part of this balancing effort too.

God speed my friend!

Link to comment
Share on other sites

Well, the stock aero fix is a whole lot easier than I imagined. Didn't even do any math or look up proportions or nothin'. Just take a half ton off each SSME so they weigh 3.5t apiece, and change the nosecone mass to 5.8t. Next, remove all monopropellant from the mkIII cockpit. That's it. The CoM is now in the correct spot, and the orbiter will glide and land just fine. I haven't tried FAR yet.

Link to comment
Share on other sites

10 hours ago, White Owl said:

Well, the stock aero fix is a whole lot easier than I imagined. Didn't even do any math or look up proportions or nothin'. Just take a half ton off each SSME so they weigh 3.5t apiece, and change the nosecone mass to 5.8t. Next, remove all monopropellant from the mkIII cockpit. That's it. The CoM is now in the correct spot, and the orbiter will glide and land just fine. I haven't tried FAR yet.

Just a question, how do you impliment these stats into the parts? Plus for the ssme, its the one that comes from direct right?

Link to comment
Share on other sites

16 hours ago, SpaceBadger007 said:

Just a question, how do you impliment these stats into the parts? Plus for the ssme, its the one that comes from direct right?

You could write a ModuleManager patch to edit the masses on launch, or just go straight into their .cfgs and edit them that way :) For the SSMEs, that's what I'd presume. However, I'm not entirely sure

Now that I'm back home, progress will start to be made again. I've still got some work to do, but it's going well so far! I'm certainly learning a lot of tricks and notable things to remember for later work.

NBuDnxH.jpg

Link to comment
Share on other sites

I just had an idea about some What-If Spacelab configurations.

They were going to do flights with Module- Pallet Combos like the ones depicted below,

(The only one that actually flew with both a pallet and module was STS-9)

https://upload.wikimedia.org/wikipedia/commons/e/ed/SpacelabFCs.jpg

Perhaps you can include support for configurations like those above in the mod.

And while I'm at it, you might want to check out this interesting article about an early (and rather unrealistic)

Flight Assignment Schedule from 1977(!) It includes stuff like launching satellites like LDEF in 1980.

http://spaceflighthistory.blogspot.com/2015/07/what-shuttle-should-have-been-nasas.html

Edited by Frednoeyes
Link to comment
Share on other sites

Hey MrMeeb (first post alert :-P). Just wanted to congratulate you on your quite frankly amazing mod, It is beautiful and I can't wait to see where it goes down the line. I made a forum account just to say thanks, thats how happy it makes me <3.

On the other hand, KSP-AVC flags the mod as v0.11 and says "do you want to update?" even though I have the release in the OP. Am I missing something?

Link to comment
Share on other sites

On 8/31/2016 at 3:18 AM, Frednoeyes said:

-snip-

What did you have in mind as far as 'configuring'? There should be room in the cargo bay for Spacelab and one of the CA Spacelab Pallets (possibly more...I haven't used them myself yet), if you leave out some parts of the tunnel.

27 minutes ago, TheRedTom said:

Hey MrMeeb (first post alert :-P). Just wanted to congratulate you on your quite frankly amazing mod, It is beautiful and I can't wait to see where it goes down the line. I made a forum account just to say thanks, thats how happy it makes me <3.

On the other hand, KSP-AVC flags the mod as v0.11 and says "do you want to update?" even though I have the release in the OP. Am I missing something?

Thanks! :) 

The AVC thing is a known bug...I hadn't quite figured out how it works, so updated the .version file online, but not in the file. The download is the most up-to-date version.

Edited by MrMeeb
Link to comment
Share on other sites

39 minutes ago, CobaltWolf said:

(Sorry RedTom, just trying to tease Meeb)

It's okay CobaltWolf, but shouldn't you be racing Beale? I heard something about an N1-killing Module Manager Config? :P

Btw playing around with different sizes of kerbol atm and can't quite get BDB to balance, is there a mod I'm missing?

When I had stock I always had enough delta V to escape kerbin's SOI (early ones like vanguard), now I dont seem to have enough to get into orbit with historically accurate looking rockets? 

TL:DR what sort of solar system is BDB balanced for?

Love your mod too btw :)

Link to comment
Share on other sites

KvccVC0.jpgHH0c8jz.jpgiI78393.jpg

 

 

 

 

 

These three pictures took about an hour to render...but the shadows look nice!

So I've started work on one of the deployable racks that were built into Spacelab's airlock, onto which experiments could be mounted. The plan is that you'll be able to conduct an exposure test, which will deploy this rack to space for a nice science reward. The problem is, I don't know what to put on the rack. I've tried to fill it with some 'generic' packages, but I can't seem to get some satisfactory variation, so I thought I'd ask anyone if they had any ideas. I think I would especially appreciate any information on the kind of things that were actually put on them. Some of you seem to be a lot better at finding random PDFs on these things than I am

Edited by MrMeeb
Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...