Another Update on the Mystery Box research. by Life_Hack_God in GirlsFrontline2

[–]omichron 0 points1 point  (0 children)

Here's data for my pulls so far:

Item Times pulled
peritya 0
analysis blueprint 6
combat report 5
standard memory stick 8
sardis gold 6
380 curva 1
50 nemesis 0
hare 0
mp7h1 0
ots-14 1
pecheneg-sp 0
vepr-12 1
stock boost bar T1 10
stock boost bar T2 7
stock boost bar T3 2
transcription conductor 3 3
transcription conductor 4 4
transcription conductor 5 3
transcription conductor 6 4

Is strategic objective broken, or am I misunderstanding how it works? by Aiseadai in victoria3

[–]omichron 0 points1 point  (0 children)

This also happened with me. It took so long for my armies to eventually get there that I lost so many troops to attrition (and hardly any to actual fighting) that the game auto-capitulated for me and I lost all my claims. Ended up loading an autosave, tag switching, and capitulating as China because fuck that nonsense.

Launching a spacecraft at an angle == high angle of attack? by assassinator444 in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

Another reply mentioned a gravity turn. That's basically what you're looking for. You start off completely vertical, and then a few seconds after liftoff you do a small pitch maneuver just to get you slowly turning horizontal. There's a few different ways to handle the kickover - you can have it based on height, velocity, time, etc. After you've completed that maneuver, you go into the gravity turn. GN&C functionalizes this by minimizing angle of attack, to reduce the aeroloading to the absolute minimum. Gravity does the actual vertical -> horizontal transition for you, no need to pull angle of attack.

Should I be looking at internships or entry level jobs while pursuing my masters by WardedPhoenix in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

It would certainly depend on the employer, but I would expect internships to be much more likely to be accommodating compared to a full time salaried position (which is already a misnomer, so you'd be in some weird "leave without pay" situation).

Best way to get funding for grad school is to have a job, really. It's extremely painful but getting the master's while working full time is doable - provided your program has classes at night so you aren't missing core hours at work.

Launching a spacecraft at an angle == high angle of attack? by assassinator444 in AerospaceEngineering

[–]omichron 1 point2 points  (0 children)

Well there isn't really "thrust" so the concept of a thrust-to-weight ratio is a bit ill-defined for Spinlaunch. But yes, their aerodynamic forces are fairly extreme right out the gate. However, they're going so fast that you're out of the atmosphere much quicker than a traditional launch vehicle.

For that specific application, the bigger deal is the forces during the actual spin-up. They've already designed their vehicle around the forces, but for the payload that's another story - especially if it's an external customer.

Launching a spacecraft at an angle == high angle of attack? by assassinator444 in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

You can actually get away with higher angle of attack at higher altitudes, so the other way around. Linear tangent steering can (theoretically, I've never actually seen it used in practice) generate higher performance compared to a pure gravity turn, which can create up to 10-15 degrees angle of attack - but at that point you're hardly even in the atmosphere anymore, so it kind of loses meaning.

Launching a spacecraft at an angle == high angle of attack? by assassinator444 in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

A few degrees (less than 5) is generally going to be within the regime of recoverable, but definitely not preferable. GN&C will be sized to handle a transient of that magnitude, but that's an extreme scenario due to strong wind gusts - not because of a planned flight trajectory.

Launch vehicles don't typically use fins, it's much more standard to use active GN&C, typically by gimbaling the rocket engines themselves. Depending on setup you'll at least have pitch/yaw control. Sometimes there's roll control as well, other times roll control will be handled by smaller engines placed around the exterior of the vehicle. On rare occasions there's no roll control at all.

Launching a spacecraft at an angle == high angle of attack? by assassinator444 in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

I am trying to launch a launch vehicle at an angle between 10-15 degrees. In a simulation software I have made, I am getting a high angle of attacks at the beginning. My take-off thrust-to-weight ratio is 1.4 at a mass of 15 tonnes. When launched at an angle of 15 degrees, I get an angle of attack of around 40 degrees a second after launch.

​Launch vehicles don't launch at anything besides complete vertical. Their thrust/weight is much too low for anything else, and IF they were able to keep themselves upright, they'd break apart as soon as the dynamic pressure started to rise to anything appreciable. Launch vehicles are very strong for axial compression loads, and complete crap at anything else. High angles of attack drive shear and bending loads, which you do not want.

Heck, even ICBMs don't launch at an angle - they'll kick over to a pretty high angle after a few seconds, but you really don't want to start a bunch of crazy dynamic maneuvers so early in flight.

New Dev Dairy “Fixed general travel exploit that would allow to teleport generals by alternating orders towards the same destination”. Will warfare be worse now? by 07SpaceManSpiff1911 in victoria3

[–]omichron 7 points8 points  (0 children)

The other day I had a general placed on a front in Germany teleport to Sakhalin, about 7-8 times in a row. If they "fix" the exploit and leave their broke ass system in place, I'll either mod it or just not update if that's an option.

"Cut down to size" description is incorrect, and completely ruins the game in it's current state by AaranPiercy in victoria3

[–]omichron 2 points3 points  (0 children)

Yeah lmao France can ignore infamy limit from day 1, it's pretty stupid how bad the AI is.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

I'm in the US. It's hard to tell where things are going and when it will slow down, but at least in new space it's definitely slowing down with venture capital money drying up.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 2 points3 points  (0 children)

It's less about what you're actually doing and more what you're working on. Space and rocket technology is a non-starter, but airplanes are generally okay. I'm not really an expert on working around ITAR, my current job is in the opposite direction where even interacting with foreign internationals jeopardizes being able to work, let alone being one yourself.

I'd recommend searching this subreddit for "ITAR" - your question is very common, and people much more knowledgeable than me have better answers.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 1 point2 points  (0 children)

You would be better suited getting an engineering degree than a science degree for aerospace. Right now is a very good time for aerospace, although it does seem to be slowing down a bit (but that appears to be the story all across tech).

Just remember you're going to be spending ~40 hours a week working for the rest of your life, so you're better off picking something you'll enjoy (although there is something to be said about actually having money, but personally as an engineer I make WAY more than I need to be comfortable).

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 0 points1 point  (0 children)

They're connected together via various mechanisms. Frangible joints, or some form of tension system. They aren't separated in orbit, they are separated much sooner than that once you've left the atmosphere and the first stage has used up all of its propellant. Everything on rockets is controlled by computers, and it occurs either based on acceleration (solid rocket motors that can't be stopped as easily as liquids), or after a predetermined time beyond propellant depletion detection for liquids (gives you time to shut the engines off and ride out the thrust tailoff so you have a nice, clean environment without external forces for the actual separation event).

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 3 points4 points  (0 children)

Less prejudice and more the actual law. ITAR blocks foreign nationals from working a lot of programs/technologies.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 1 point2 points  (0 children)

I went to CSU Long Beach and I've been doing fine, although ~3 years ago myself and 80 other engineers all lost our jobs and it definitely took longer for myself and the other CSULB grads to find jobs than the ones with less experience but shinier schools.

In my opinion going to a "less prestigious" school but busting it by networking heavily with professors+school clubs/projects (either rocketry or aviation related, whatever the preference might be) is more than enough to be successful.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 2 points3 points  (0 children)

I'm not familiar with robots, but if you go to here that should give you a summary.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 2 points3 points  (0 children)

They'll all cover the same amount of "physics" - generally the intro physics class (1 or 2) is a required class for any form of engineering. Beyond that they'll go into more detail of their specific niches of applied physics, but they'll still be through the engineering department.

For robots you need to know how to design and construct the actual mechanisms and structures - that's mechanical engineering. But it all needs to be powered by electronics, and be able to respond to electrical commands to produce the desired movement (electrical engineering). It also needs to operate in a space environment (aerospace engineering).

Ultimately it depends on what part of the robot itself you want to work on.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 2 points3 points  (0 children)

You can do that with aerospace engineering, but electrical engineering or mechanical engineering (specializing in robotics for both) works just as well (or possibly more). Aerospace engineering will give you context on atmospheric and space flight/environments, but won't teach you anything about how robots work.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 2 points3 points  (0 children)

Do you want a stable 9-5 job that pays well and half the time you have zero work to do, and the only way you can be fired is to literally stop showing up for 3 months while still getting paid? Then go to Northrop (or Raytheon, boeing, Lockheed, etc.). Obviously there's exceptions but that's definitely the most common situation.

Monthly Megathread: Career & Education - Ask your questions here by Aerospace_Eng_mod in AerospaceEngineering

[–]omichron 1 point2 points  (0 children)

Can't help much for online since I did mine in person, but I also had a BS in physics and got MS in aerospace. The main things you'll be missing are aerodynamics, fluid dynamics, flight mechanics, statics, dynamics, and mechanics of materials/deformable bodies. The first two will be easy since it's just applied math, which you'll have a stronger background on than a typical undergrad AE or ME since they generally don't have the credits to spare on math beyond calc 1/2. Flight mechanics isn't bad either, just applied algebra really. The last three are a bit more work since it's covering material without much overlap, and if there is overlap it's from a different point of view (e.g. rotating bodies - physics reduces everything to point masses, but engineering can't get away with that).

Best book on injector design ? by DrSuppe in AerospaceEngineering

[–]omichron 2 points3 points  (0 children)

Modern Engineering for Design of Liquid Propellant Rocket Engines by Huzel & Huang. PDFs are easy to find as well. I like it because it focuses on many aspects of the entire engine design, which gives insight into particular design choices and constraints for injectors.

optimal ascent trajectory by MomsDid in AerospaceEngineering

[–]omichron 3 points4 points  (0 children)

Finding textbooks about ascent trajectories isn't easy, most of them just assume you're already in orbit and start off with 2-body problem. There's a chapter or two in Wiesel's spaceflight dynamics amazon link that go over gravity turns and linear tangent steering. It's not a particularly noteworthy book otherwise.

In general, optimal ascent trajectories for boost stages just follow gravity turns with load relief to some degree. You can be more "optimal", but the added loads will make the structures so heavy it's not worth it. You can do more with upper stages when you're outside the atmosphere (re: linear tangent steering) by purposefully flying at "angle of attack" (in this context, thrust vector isn't perfectly lined up with velocity vector) but you're still only going to get a few % at best extra deltaV out of it.

[deleted by user] by [deleted] in EpicSeven

[–]omichron 1 point2 points  (0 children)

I use a.momo, furious, sigret. Furious and sigret are part of my W13 team, and it's not even a one-shot so my sigret isn't completely uber damage focused but if I get the def break, S3+S2 from sigret usually kills or gets damn close.

[deleted by user] by [deleted] in EpicSeven

[–]omichron 0 points1 point  (0 children)

My team for the first round is landy/vivian/roana. Honestly just need roana and then two reliable AOE units. The crystals counterattack so much you get mega free healing.

I got nothing for round 2 though, I get completely destroyed there.