[1.8x - 1.11.x] Stockish Project Orion v1.8.2 [update 12/29/2020]

[TiktaalikDreaming]

The NASA grade pulse units were around 141kg, I don't have exact dimensions for them.  The USAF grade units were either 79 or 86kg depending on what you read, and 33cm round by 61cm long (density of ~1.65kg/L).  I suspect we know those dimensions because they had to share that much at least when working with Coca-Cola Vending machine designers with the feeding mechanism.  As the NASA units were derivative and later than that collaboration, we just know the mass.  The NASA units were (according to the George Dyson book) missing some of the super secret tweaks to reduce the nuclear device size, so they pick up a bit of mass and probably size from that.

Pulse units for the different craft varied, which is damned inconvenient for a mod.  The big early Orions used NPUs of around 1.15tonnes each.  640kg is somewhere between what would be used on a 20m Orion and a 4000tonne (I think the 86foot?) Orion.  It's pretty damned big for a scaled down 5m Orion.

Which brings us to dial-a-yield.  This is a great improvement over the old Orion mod.  There's no sign in the documents that I've found to support them, BUT they needed different yields, and the people involved would certainly have been aware of the capability.  As far as I know, there's only really a couple of ways of doing it on purely fission devices, but both are likely to be available on units where size is critical, as they're both about varying neutron flux "artificially" which is needed to shrink the primary fission system.  Critically for the mod, it makes it much easier to use.  We can argue all day about whether they would risk the added complexity or if the added neutron flux from the capability is a good idea in a crewed craft full of enriched fissionable material.  But Kerbals don't care.  It aids boom boom.

I've just started going through some of the code.  I tried and failed several times to get up to speed to rewrite the old Orion mod, but with zilch experience in C# I struggled a bit.  And the final disabling of extending part rather than partmodule basically killed my chances of fixing it.  It looks like the plate movement is based on an animation.  Excellent   And the primary and secondary suspension move properly.  That makes me inordinately happy.   

[SuicidalInsanity]

The NPU mags are that heavy due to pulse units being 645 kg each. 0.645*60 = 38.7 tons. As for why they are 2/3's of a ton per bomb is something of a fudge on my end to come up with something between real-world numbers and KSP. RL numbers for pulse units - 1st gen pulse units using '60's tech - as noted were from 86-140 kg for 1kt, looking at what docs I could find gave 1152 kg for 5kt. My main concern was I wanted one unified propellant resource - hence the variable yield instead of having to juggle n different discrete yields (and n different fuel tanks). Problem with variable yield is mass needs remain constant, so all those bombs are going to mass whatever a max yield device would - lower yields are now super heavy/inefficient. 645 kg seemed an acceptable compromise between 150 and 1150 kg for 1-5kt units. That said, looking at the masses for TD's Orion pulse units it looks like I've been too conservative in how I'm scaling things - TD had 5tk units be 549kg, so a revision of pulse unit mass is something that'll happen for next update.

5 hours ago, TiktaalikDreaming said:

I tried and failed several times to get up to speed to rewrite the old Orion mod, but with zilch experience in C# I struggled a bit.

Same. Not going to lie, your Orion mod directly inspired this one; I initially wanted to see if I could resurrect the plugin, but the changes needed to get it working meant it was far easier to just code a new one from scratch.

Edited June 7, 2020 by SuicidalInsanity

[TiktaalikDreaming]

1 hour ago, SuicidalInsanity said:

Same. Not going to lie, your Orion mod directly inspired this one; I initially wanted to see if I could resurrect the plugin, but the changes needed to get it working meant it was far easier to just code a new one from scratch.

Yeah, that's where I was going to go if I had the time.  I've just never had that time, and to be honest, it was the interaction with KSP's api that baffled me the most.

For the record, "my" Orion mod was basically an updated parts mod on top of Nyrath's Orion mod which was actually the work of a bunch of people.  Nyrath being the Winchell Chung who runs the Atomic Rockets web site with all this nice info http://www.projectrho.com/public_html/rocket/enginelist3.php#boomboom

The only stuff I really did with the plugin was fix a reference after it changed once, and ad some tweaking to account for atmo.  I can code math, even in C#. 

[GrandProtectorDark]

6 hours ago, SuicidalInsanity said:

. My main concern was I wanted one unified propellant resource - hence the variable yield instead of having to juggle n different discrete yields (and n different fuel tanks).

I do think having just 1 set of fueltanks is rather nice. Makes it a lot less of a hassle than compared to dozen of nuke disks from TD.

I think RDs Orion had a rather good solution to it. Using a fuelswitch plugin to minimize the tanks needed. Although I don't know how that would work with choosable yield.

6 hours ago, SuicidalInsanity said:

TD had 5tk units be 549kg, so a revision of pulse unit mass is something that'll happen for next update.

Pulse Unit mass aside. As I've already mentioned, The amount of pulse units per magazine could be looked at again too.

[GrandProtectorDark]

On a different note.

I Took my time to do something for which Project Orion was made for

Going on a Journey to a far out gas giant (from a mod called "Salus").
Works surprisingly well and it hasn't shaken itself apart.
The acceleration is also pretty good after I got a hang of how many of these heavy pulse unit magazines I actually need.
(Also the "umph" of the explosions is really nice)

However,An Issue that I found, while you did add the ability to edit the max yield, and the edited max yield also shows up in the editor, Inflight it still only seems to go up to 5kt
 

[Sol469]

In 1.9.1 I cant use the extra pulse unit magazines, they simply dont work, I have tried everything, even fuel lines but it just wont work, it says "transfer pulse units" and I cant find a way to do that, so its basically only 225 nukes only for the entire mod.

[SuicidalInsanity]

At present, nukes are transferred manually via the part action window using stock fuel transfer - Right-click on the the Orion, Alt+Right click on a magazine, then click the Out button to transfer from the latter to the former.

[SuicidalInsanity]

Finished the Medusa - now you too can turn your Kerbals to stone give them searing eye burns with its gaze!

Update 1.8 - GitHub | SpaceDock

Changelog:
  -New part: Medusa Drive
  -Adds Medusa Drive example craft
  -Fix flight GUI yield select for custom max yields > 5 kt
  -Reduced A.P.U mass - nuke magazines shouldn't be quite as absurdly heavy now.
 

Edited June 18, 2020 by SuicidalInsanity

[Apelsin]

Hey, great work on the mod, been enjoying it for the last couple of days. One odd thing I noticed though: why is the Orion drive placed so early on in the tech tree? (I'm using CTT btw). I think despite all the trade-offs it is should still be around the very end of the propulsion branch.  

[DStaal]

55 minutes ago, Apelsin said:

Hey, great work on the mod, been enjoying it for the last couple of days. One odd thing I noticed though: why is the Orion drive placed so early on in the tech tree? (I'm using CTT btw). I think despite all the trade-offs it is should still be around the very end of the propulsion branch.  

They had test versions built before we got to the Moon.

[GrandProtectorDark]

1. The medusa Is cool. It's running animation is just perfection. 

2. reduced apu mass. Nice

3. I noticed that the bombs have an actual model. Nice detail for something only really visible for a second

4. did you adjust the acceleration again? The pulses do feel more spread out over the pushed-retraction (or pushed-extension with medusa) phase of the detonations (like what tiktaalik mentioned). It's nice

[SuicidalInsanity]

Update 1.8.1 is now up - SpaceDock | GitHub

More a tune-up than new content - Changelog:
-KSP 1.10 Update
-Fixes inverted nodes on 1.875-3.75m adapter
Engines now respect Infinite Propellant Cheat
-Added Per-pulse dV display
-Nukes no longer instantly vaporize asteroids/comets

[jimmymcgoochie]

When I tried to use the Medusa engine with physics warp (x2), it explodes every time and disassembles most of the craft it's attached to. Not sure if the bomb is just exploding too early, the bombs are set to 2.5kt but only pulling 2-3g acceleration each time.

[SuicidalInsanity]

The vessel is being shaken to pieces, or the Medusa itself is exploding, resulting in a RUD?
If it's the former, the nature of physicswarp means parts are being subjected to greater impulse per frame, due to fewer frames to spread the impulse over. Running a quick test, you'll still want struts (either physical strut parts or autostruts), at least for the heavy stuff -A.P.U. magazines, larger fueltanks, anything at the end of a long stack of parts that can noodle - for vessels under physicswarp.
If it's the latter, I'm going to need logs, because it never did that during testing.

[AntaresMC]

Can it be made to generate KSPIE's WasteHeat?

Orion would be quite heaty, and I dont really think Medusa could be used without IgnoreMaxTemp.

Assuming 1000KN at 5000s Isp, (I havent played the mod and there is little info out there, sorry if Im wrong) its got around 5 gigawatts, probably a bit more since the "nozzle" is quite inefficient. Medusa would have around a TW, so not quite worth it in terms of heat...

Also a minimag orion would be very cool

Edited July 11, 2020 by AntaresMC

[SuicidalInsanity]

Yes and no? Adding generating a resource during operation should be fairly trivial; that said, Orion classic was actually fairly heat neutral, surprisingly enough - between ablative oil coatings applied to the plate before each pulse (Carbon and Hydrogen absorption spectra minimize heating) and the copious amounts of Beryllium Oxide filler included in the pulse units to absorb and downshift the EMR wavelength of the detonation from hard X-Ray to UV (Plasma is generally opaque to UV), the pusher plate was expected to experience minimal heating. (I want to say predictions were something in the range of 0.7 deg. C increase per pulse, but I can't find the source I came across that number, so don't quote me on that.) So some heat, but nowhere near the level of on-board reactors.
Medusa though? Medusa IRL would get toasty. Lot of bits exposed to X-Ray nuclear fury. I'd need to find the relevant calculations (or someone else who knows the KSPiE heat mechanics would need to chime in) for proper numbers, but again, adding a resource (WasteHeat) should be trivial, so it would mainly be a matter of putting proper numbers in the .cfg.

Minimag Orion would be very doable.
 

[AntaresMC]

20 hours ago, SuicidalInsanity said:

Yes and no? Adding generating a resource during operation should be fairly trivial; that said, Orion classic was actually fairly heat neutral, surprisingly enough - between ablative oil coatings applied to the plate before each pulse (Carbon and Hydrogen absorption spectra minimize heating) and the copious amounts of Beryllium Oxide filler included in the pulse units to absorb and downshift the EMR wavelength of the detonation from hard X-Ray to UV (Plasma is generally opaque to UV), the pusher plate was expected to experience minimal heating. (I want to say predictions were something in the range of 0.7 deg. C increase per pulse, but I can't find the source I came across that number, so don't quote me on that.) So some heat, but nowhere near the level of on-board reactors.
Medusa though? Medusa IRL would get toasty. Lot of bits exposed to X-Ray nuclear fury. I'd need to find the relevant calculations (or someone else who knows the KSPiE heat mechanics would need to chime in) for proper numbers, but again, adding a resource (WasteHeat) should be trivial, so it would mainly be a matter of putting proper numbers in the .cfg.

Minimag Orion would be very doable.
 

Ok, I can make the numbers. And then you should add stock ablator usage and an ISRU (stock ore is enough). I can do the math as well.

Medusa I said I dont think is possible in HumanSpaceProgram cuz heat. A terawatt is unsaveable by deign and a sail is very inneficient, so probably more. And the sail cant be a good rad as its gonna be DESTROYED by n embrittlement if thin or radiation optimized

MMO, YEEEESSSSSSS!
I can make everything its needed, I really like the concept. I think I could help and Id like it XD

Basicly we have to make a good size for the minimags (I think the U used for ISRU would be a good resource), aka the kick per shot, an Isp of 10-20Ksec may work and trust dependant on pulse rate and afterburning if needed. I wonder if afterburning can be done in regular orion (Its not needed, probably counterproductive, but whatever, curiosity)

Edited July 12, 2020 by AntaresMC

[SuicidalInsanity]

"Mini" Mag Orion, apparently using the same definition of mini that miniguns use:

This is 1/4 scale, btw; Real-World variant is 20m diameter. Not shown: magazine stacks and the massive radiators needed for its multi-MW power system and on-board nuclear reactors.
From what scarce documentation I can find, in-game stats would be ~60 tons, Isp 9500-ish, ~650 -1250 kN/Pulse, 1 pulse/sec. Not a lifter engine, but definitely something useful for cruising about the outer solar system.
 

[AntaresMC]

On 7/14/2020 at 4:21 AM, SuicidalInsanity said:

"Mini" Mag Orion, apparently using the same definition of mini that miniguns use:

This is 1/4 scale, btw; Real-World variant is 20m diameter. Not shown: magazine stacks and the massive radiators needed for its multi-MW power system and on-board nuclear reactors.
From what scarce documentation I can find, in-game stats would be ~60 tons, Isp 9500-ish, ~650 -1250 kN/Pulse, 1 pulse/sec. Not a lifter engine, but definitely something useful for cruising about the outer solar system.
 

I love it, certainly cant w8 until implemented

depending on the efficiency of the mag nozzle and Z-pinch mechanism it can get up to 10000s and it would be possible to circunvent the huge inneficiency of the system by adding a small D-T or D-Li7 core. Maybe up to 20000s. Idk how to simulate it without going deep into realism/complexity. Maybe the bigger the shot the higher Isp but more abrupt shocks so more struts needed?

the number of pulses per sec would be limited by the amount of radiators or ablator. The size of the magazine (and its speed) can be changed in flight from a huge uranium tank and something to cut and crush it (maybe a separate part like an ISRU thing?). It could also be afterburned with every propellant, which would increase thrust and smooth out blows at the expense of Isp

also, the img I had from atomic rockets was an exact 1/2 sphere of nozzle. Its not really important, but whatever

Edited July 16, 2020 by AntaresMC

[broberds]

Love this mod dearly.  Are there any plans to make it compatible with RSS/RO?

[Nantares]

On 4/2/2020 at 9:24 AM, SuicidalInsanity said:

Nuclear Pulse Units are nukes. it is recommended to not operate an Orion drive near any launch pads, lunar bases or orbital stations you particularly like. Replacing the Launchpad at the KSC can get expensive.

I tried to use Orion Drive to get to orbit, but it becoming an Orion Drive-powered ICBM instead

[SuicidalInsanity]

Some WiP 10m stuff for 'full-scale' Orion, like the 4000 ton and battleship proposals:

Current idea is just provide fairing/aeroshell pieces and players can stuff whatever they want inside (Above pic has 2 8m cargobays and a hollow 10m-7.5m structural fairing, giving something like 1500 cubic meters of usable volume), with maybe a select few 10m parts.

[hemeac]

On 8/13/2020 at 6:00 AM, SuicidalInsanity said:

Some WiP 10m stuff for 'full-scale' Orion, like the 4000 ton and battleship proposals:

Current idea is just provide fairing/aeroshell pieces and players can stuff whatever they want inside (Above pic has 2 8m cargobays and a hollow 10m-7.5m structural fairing, giving something like 1500 cubic meters of usable volume), with maybe a select few 10m parts.

Looks great. Are there any recent mods that have 10m tanks and engine plates to create launch vehicles or would those be part of the select few parts?

[SuicidalInsanity]

No idea about other mods. SpaceY might, I remember it having 7.5m parts, at least.
I hadn't considered launch vehicle parts, to be honest, but an engine plate will be among the 10m parts.

 

 

[hemeac]

1 minute ago, SuicidalInsanity said:

No idea about other mods. SpaceY might, I remember it having 7.5m parts, at least.
I hadn't considered launch vehicle parts, to be honest, but an engine plate will be among the 10m parts.

 

 

Sorry was a bit unclear, I meant fuel tanks and engine plates.  Think Near Future goes up to 7.5m parts and the old Space Y (Expanded or something) went up to 10M, but the latter textures don't quite match up with what current creators have been producing.  But a 10M engine plate would be great.  Rescaling liquid fuel tanks to 10 meter myself from Near Future Launch Vehicles is fairly straightforward if that isn't in your plans.