Who Else Does Rocket Science MATH?

[Tank Buddy]

I did up until last week, now I use KER because it got too tedious.

Also, I tend to be able to estimate if a rocket will work, so it never really mattered until I tried Moho or constructing specific function spacecraft (like Mun escape pods with just 250 m/s DV)

Edited March 29, 2014 by Tank Buddy

[Ralathon]

I sometimes do it for things like Apollo missions, where engineer gets confused about the docking. But in general I let the computers do it for me, we invented those things to free us from these tedious calculations after all.

Only thing I really use math for on a regular basis (In KSP, physics student means I need it plenty) is RemoteTech constellations. First to figure out my height range and to find an orbit with a nice (divisible by 3) period and later to precisely place my sats at 120 degree intervals.

[LameLefty]

I did structural design, propulsion performance estimates, aerodynamics and orbital mechanics with a mechanical pencil, engineering quad-ruled paper and my trusty HP calculator back in college in the 80's because that was the only option. None of that counts as "fun" for me anymore, sorry.

[cantab]

I did some of my own dV calculations. I know I can do them. So now I let KER handle it.

SlyReaper, props for explaining the transfer windows though. That's something that had rather baffled me.

[Godot]

Did it for a while via Excel, before I discovered kerbal Engineer Redux.

Now I let KER do all the work and only notice basic values of my rocket types in Excel (like total costs for a rocket [or specific stage], or its dV and intended Payload)

[tygoo7]

I like to do it sometimes but other times I just use engineer.

[Decho]

If someone is interested in literature about orbital mechanics and space maneuvers basics may consider looking at this book:

If you want to go further than that then Vallado is the ultimate tome (and as far as I've come across pretty much the industry standard), see here: http://books.google.co.uk/books/about/Fundamentals_of_Astrodynamics_and_Applic.html?id=PJLlWzMBKjkC&redir_esc=y Good luck getting one cheap though.

As for KSP I don't do much maths, just first order trajectory stuff to get me going roughly the right way, and delta v calculations for payloads if they're going a long way.

[Dust]

Someone once posed a similar question and one of the responses was along the lines of "No way, if I have to do math then it's not fun anymore." and I totally disagree! To each his own. Spreadsheets, formulas and calculations can be fun, too! When I suspected KER wasn't correctly calculating the dV of my interplanetary ships I learned how to do the rocket equation to confirm it. When I started using RemoteTech2 I taught myself how to solve orbits for altitude, period, velocity, etc. for configuring relay satellite networks (and from there also played with calculating orbital transfer burns). For rendezvous burns and suicide burns I learned how to calculate the distance from target I should start burning.

It especially gives me something to do at work when I want my KSP fix.

Edited March 29, 2014 by Dust

[AlternNocturn]

I'm not interested in pursuing a career in engineering and rocket science so I don't do any kind of math when playing KSP. I play the game like an RPG or a MOBA: In my mind, I assign a value to parts based on their stats, and I subconsciously use that value to gauge how well I expect the rocket to perform, and it usually works out.

[metl]

Who has time for math? If at first you don't succeed, build bigger!

[FanaticalFighter]

I use math when the ship designs get too complicated for KER. As in, when I plan a mission where the staging is very weird, or a mission like Appolo were the lander meets the mothership, KER tends to get delta v's wrong, so I use the math to get the delta v there.

[Madrias]

I tend to apply my own insane logic to the game rather than math. Build it and fly it. If it flies into the ground, add more thrust. If it still flies into the ground, add more lift. If it still ends up in the ground, add more SAS and more lift. If it's still crashing, you need less weight or more thrust...

[magnemoe]

Has used the rocket equation a few times where mechjeb had been unable to calculate stage dV, mostly on my 100 ton grand tour. The lander also used fuel I had to factor in.

Other times then I had to decide if I could return to Kerbin with the docked lander as second stage or leave it in orbit and return with the interplanetary ship.

[nettcod]

I (almost) always use math for designing rockets. That way I know it will have enough ÃŽâ€v and TWR for it's mission and I'm not just guessing and hoping it works.

[User Unrelated]

I'm taking a satellite dynamics course, because space...

and my professor asked the class if anyone knew what a Hohmann transfer was...

I, of course, raised my hand.

She asked me to spell it because she didn't believe me haha

my notes seem to be quite abbreviated compared to people around me. It's nice knowing what most of the jargon already is.

My professor uses Perifocus and Apogee, though... technically correct but it makes my brain think harder than it should have to. I just write Ap and Pe everywhere

I've actually been thinking about how I might be able to write my own mod to display basic orbital information... I already have a mod for that, but knowing that it was my own code that was working for me, that'd be a bit more satisfying!

I appear to be the only KSP player on my campus, because I'm sure we'd all be taking this class together if there were any others out there... nobody else seems to really care, it was rumored to be an "easy-A" that satisfies a technical elective credit (We need a certain number of them)

and when some of the other courses are "Advanced Numerical methods", and "Analytical fluid dynamics" a class about space seems pretty interesting!

EDIT: I saw something about textbooks...

The textbook for this class is called "Modern spacecraft dynamics"

and it was printed in...

drumroll please...

1976.

It is a hardcover, with embossed gold lettering and a little satellite on the front.

classy.

It is a terrible textbook, though.

Edited March 29, 2014 by User Unrelated

[LethalDose]

Yeah, I do my own math for missions to ball park mission requirements and launch angles.

I'm also surprised noone has mentioned Scott Manley's

. Or at least not that I saw.

[Ravenchant]

I derived some equations for delta-v as a function of payload mass, and used Kepler's laws a few times, but since I discovered KER and alexmoon's page I really can't be a**ed to do it most of the time. Plugging numbers into existing equations isn't math, it's tedium.

[KvickFlygarn87]

IdoIdoIdoIdoIdo!

[Silverchain]

"Analytical fluid dynamics" a class about space seems pretty interesting!

Part of my degree was about plasma fluid dynamics in the sun, and it was appallingly complex. I'd've liked five bloody minutes alone in a room with Lev Landau...

KSP rocket science is about my level these days.

[DivisionByZero]

I do this, maybe far more than I should.

When I started playing they had just added science instruments like the thermometer, etc. I was also reading up on the drag model used in KSP and how the default wasn't physically realistic so I decided to test it and try and see if I could work out the model the game was using. So, I did a series of launches where I had a science instrument showing the display and during launch I'd pause the game, note the time, velocity, and whatever science instrument was in place. I did this for the engine ISP and everything. I then wrote a 4-5 Runge-Kutta program in Octave to simulate the launch using all the knowns and back out the unknown drag force, and hence, the drag-force model. It worked pretty well, and I think I can tell you what impact changing to a non-isothermal, ideal-gas atmosphere will have on the existing game parts.

It got pretty involved.

Now this thread has inspired me to think about working something out so I can plan aerobraking maneuvers with Ferram installed...

[DocMoriarty]

What is math please? I'm a Kerbal. I use my feeling and the FORCE. And guess what? In most cases i'm precisely on the spot with my designs.

But the whole truth is, that i know the math from Orbiter already and also played 1000+ hours in KSP and simply need no math most of the time because i have lots of experience with what works and what not and how much glue and tape i need. And when i'm a bit unsure as for space trains to outer planets i simply add in more of my fuel tank modules to my space trains and then it will be enough in any case. And if it wasn't enough, i simply pretend i never planned it as return mission.

[nadreck]

Hey, back when I was in high school my local library had the following 12 year old book in the discard bin and I decided to give it a good home:

Even before I picked that one up in 1974 I would doodle rocket designs in class using the rocket equation quoted here and a number of other relatively simply bits of math and my variety of "seat of the pants" KSP certainly includes a lot of that sort of simple arithmetic. For something like my upcoming Eve science lander, I will use some of that math, but I will ignore the impact of atmosphere, instead I will test the vehicle on Kerbin and make sure that what I expect to make it down safely to the surface of EVE can launch and make it to 10,000 meters altitude and from there the remaining vehicle should be able to launch from the ground on Kerbin and make it to trans Munar orbit (and note that is just what is needed to make it to Low Eve Orbit - from there it docks with the return vehicle and at least the science module and Kerbal come back to Kerbin).

I have yet to try navigation further than the Kerbin SOI without the node planner that comes built in to KSP and http://alexmoon.github.io/ksp/ but sometime I probably will. I do manage to do higher energy orbits than Hohmann transfers.

[brdavis]

My professor uses Perifocus and Apogee, though...

I actually use (when teaching) pericentron and apocentron, although periapse and apoapse are just as well… but i never understood why anyone would use perigee (and perihelion, and pericynthion, and perijove, etc., etc…)