Mechjeb: Realism or not?

[Boosterspice]

Fellow kerbonauts,

Recently I sat down and looked at the numerous realism mods, when it struck me that mechjeb may be a realism mod. Why? Because very few rockets and satellites are controlled by people on the ground and/or in the rocket. The ground and onboard flight computers usually do that job, and since mechjeb is an automated flight computer, doesn't that make it a realism mod? And in that case, should it be advertised as one and/or included in certain realism overhaul mod packs?

Feel free to express yourself

[CalculusWarrior]

I feel like a programmable computer such as kOS is more realistic, as you physically have to type in what you want your rocket to do. That being said, Mechjeb does bear some similarity to autopilot systems used today.

However, it does serve to make the pilot's life easier, and realism mods are generally focused on the opposite of that

[Red Iron Crown]

Yes, it's realistic.

Autopilot is realistic. Every accomplishment manned spacecraft have achieved was achieved first by automatic systems, with the exception of docking. Modern spacecraft, including manned ones, rely on automatic systems for every phase of flight, with manual systems relegated to backups in case the automatic systems fail for some reason.

Same with construction data. No space program designs rockets without examining thrust-to-weight and delta V parameters, it would be folly to do so.

Same with instrumentation. Real spacecraft have easily accessible orbital information.

Of course, realism is not necessarily Squad's goal with KSP. They seem to feel that there is value in designing craft "from the hip" and performing all maneuvers manually.

[jwenting]

what Red says. MechJeb is probably the most realistic of all the realism mods.

There is value in doing things by hand, and on earth that's how we gained the knowledge to first program those computers to do things.

Not by sending men into space on rockets without any automated systems, but over decades of designing ever more complex sub orbital rockets with a slide rule and a rabbit's foot, 90% of which blew up and 90% of which that didn't blow up end up somewhere else than intended.

[Deta]

Real, the kerbin/human reflexes are not fast enough;.; to do the RCS burns but a MJ can as it would in RL. only really fly the ship is when the flight systems fail. but again to each its own.

[LawnDartLeo]

Nothing unrealistic about MechJeb. If people want the unrealistic challenge of not using it, that is their business.

KOS is MechJeb sans the fancy user interface and automation.... more or less. If you are game for creating code to accomplish things, KOS will keep you entertained for a long time.

[Legendary Emu]

I don't like mechjeb because it makes everything way too easy. But I still think autopilot is good because it makes the tedious parts of getting into Kerbin orbit or getting into Mun orbit from Mun surface and stoof like that. So KOS would be my realism mod.

[vger]

I do tend to think it's too easy, but then, I don't use the Mechjeb autopilot. I just have it for the additional info. Frankly, I doubt I could keep from crashing a lander without it. KSP's 'surface speed' indicator combines horizontal and vertical velocity making it somewhat difficult to know where you should be thrusting. And if you want to know for sure whether you're going up or down, you have to bounce your eyes to the top of the screen. And then there's the KSP altimeter using only sea level as a guide, which is a VERY dangerous thing to go by.

I also like knowing my apoapsis and periapsis, without having to switch to orbital mode all the darned time.

And yeah, Mechjeb autopilot is quite realistic.

[Saltpeter]

Tens of Hohmann transfers over Kerbin get pretty monotonous, and my space station is 5-frames-per-second large. The rendezvous and docking autopilots make it easier for me to take. I think when realism mods make a game easier it's a triumph of humanity. ;>.>

[Hodo]

MJ is about as real as anything else in KSP. I know real life aircraft autopilots are good but have more functional controls built into them, and do a far better job of handling aircraft than MJ does. Don't believe me, ask MJ to land an aircraft from 100km out at KSC with FAR. It wont be pretty.

[Red Iron Crown]

MJ is about as real as anything else in KSP. I know real life aircraft autopilots are good but have more functional controls built into them, and do a far better job of handling aircraft than MJ does. Don't believe me, ask MJ to land an aircraft from 100km out at KSC with FAR. It wont be pretty.

FAR is such a game changing mod that I don't think it's reasonable to expect an autopilot programmed for the stock game to work well or at all with it.

[Sirrobert]

I think it's completly realistic yes.

Mostly the deltaV. Planning with a deltaV map how big your rocket needs to be is how it actually works, instead of just making it big and hoping you have enough fuel to get to whatever planet you want to go and back.

I mostly use the autopilot to take over repetitive tasks that I've done over and over already. And excecute manouver nodes.

The main thing I use it for is excecuting tiny manouveres to fine tune planetery encounters (.5m/s by hand is nearly impossible)

[Boosterspice]

I use it for orbital manouvers and the beloved delta-V information. That is where it is really handy.

I agree with all you, mostly. Yes, kOs makes it half automatic and more fun for the player, but MJ has a similar function, the Translatron. But hey, each kerbal to its own

[Arran]

MJ is unrealistic in its form in KSP, i doubt any NASA astronaut would dare to step into a rocket controlled by MJ

Also a other big difference between RL spacecrafts and KSP crafts, we have in KSP one autopilot to fly them all , NASA has a autopilot catered for that vehicle only.

Having that said, having a autopilot is realistic, even the first "rockets" had some mechanical guidance and later on dispite beeing very simple, and automated guidance system, to nowerdays fully functional systems that could fly the crafts completely without any human interaction at all..

[m4v]

I suppose is likely that you can't pilot any rocket or space craft manually IRL, there's always an autopilot or guidance system, however, NASA doesn't fly rockets in an universe that can be described with just a bunch of simple deterministic formulas.

[Capt. Hunt]

MJ is unrealistic in its form in KSP, i doubt any NASA astronaut would dare to step into a rocket controlled by MJ

Also a other big difference between RL spacecrafts and KSP crafts, we have in KSP one autopilot to fly them all , NASA has a autopilot catered for that vehicle only.

Having that said, having a autopilot is realistic, even the first "rockets" had some mechanical guidance and later on dispite beeing very simple, and automated guidance system, to nowerdays fully functional systems that could fly the crafts completely without any human interaction at all..

I suppose that's somewhat true, in that MechJeb is somewhat unrefined, real NASA autopilots likely take better account of things like fuel consumption, which Mechjeb doesn't care about, that being said, the Mercury Capsules were almost completely computer controlled.

[Rusty6899]

I think it's completly realistic yes.

Mostly the deltaV. Planning with a deltaV map how big your rocket needs to be is how it actually works, instead of just making it big and hoping you have enough fuel to get to whatever planet you want to go and back.

I mostly use the autopilot to take over repetitive tasks that I've done over and over already. And excecute manouver nodes.

The main thing I use it for is excecuting tiny manouveres to fine tune planetery encounters (.5m/s by hand is nearly impossible)

That does assume that people who don't use MechJeb have no idea how much delta-V their craft has. I would say that it is more realistic to calculate exactly how much fuel you need for each stage rather than a trial and error process involving MechJeb, where you add a fuel tank, check delta-V, add another fuel tank etc. Obviously using MechJeb is better than cowboying it, but I think that developing your own design process and doing your own calculations is closer to reality than MechJeb.

I can see the attraction of using an autopilot for mundane tasks, and it is definitely more realistic than manual navigation, but I suppose that is part of the charm of the game.

[Camacha]

MechJeb goes aginst what the realism mods try to achieve, which is gaining a deeper understanding of the problems that arise when being in the space business. It pretty much gives you solutions and answers. I would say that kOS is more of what suits the realism mods - it not only enables distant control, it also makes you work for it. I can honestly say I have never had this much fun with applied math before.

[Fel]

*Sigh*

Can we read the precise location of where we are in the universe now, or do we calculate it with simplistic approximations and the correct via manual or instrument input?

Do we have the on-board AI execute a series of maneuvers by analyzing "the universal source code", or are they limited by the instruments on board? (Akin to how ISA-MapSat knows the geo-position without a single radar station to say "yep, you're exactly there")

I'd still doubt that NASA wouldn't perform course trajectory on their own N-Body Supercomputer than use approximations for an Autopilot. Even then, power constraints asks what is so difficult with programming in a flight plan that you need the extra power for it to be calculated and adjusted in real-time.

Be realistic here, "Autopilot" has far too many meanings to just say "NASA Uses Autopilots, QED MechJeb is Realistic". And MechJeb's ability to get utterly precise information, in real time, and make calculations on that, in real time, is a little absurd. Yes, we don't collect mun rocks, or have waste, or do anything to change the mass of the ship... but there are differences between a precise figure read from "the magic of the universe" and a calculated figure that has some error to it... and how small error builds up and eventually requires outside observation to correct for.

Whatever really. Whatever.

*In short*

Real autopilots use assisting technology to perform precision maneuvers. Without GPS and Radar there would BE no "Aircraft Autopilot", and similar approaches should be taken when talking of a space autopilot.

Edited March 17, 2014 by Fel

[Boosterspice]

So, we are basically talking two "realisms" here? Real realism and KSP realism. According to real realism, using MJ in KSP is somewhat realistic, but according to KSP realism, it's unrealistic. Is that what we are trying to say?

[Red Iron Crown]

Autopilot without GPS or radar is not only possible, but was very common before GPS went mainstream. Read a bit about inertial guidance.

You have a bit of a point in that the information MJ uses is mathematically precise, that's an inevitable consequence of KSP being a simulation and not the real thing. But the ability to perform calculations in real time is far from unrealistic, that's the whole reason computers are used for modern autopilots.

Real autopilots also have the advantage of knowing, to a much finer degree, how the craft reacts and responds to different inputs; MechJeb is more of a general solution which is well suited to KSP where craft are assembled Lego-style with nearly endless possible configurations.

I'm not really sure how one could implement the real world imprecision of orbital information into KSP. Do we want to have to sight stars with a sextant and perform the calculations manually? Would KSP really be more enjoyable if we had no map mode or instruments like the altimeter and velocity readout (all of which are also perfectly precise)?

[S1gmoid]

It would be a lot of fun to gather some articles on the navigation systems early astronauts used. I remember reading that during the Apollo mission, the astronauts got regular updates from the ground about their position and other flight parameters - data that has been averaged into a pretty accurate number from multiple measurement sites, and turned out to be more precise than any measurement the crew could make from the ship itself.

I think that having accurate and up-to date measurements that could realistically be accessible to the spacecraft or ground personnel is an acceptable simplification of real life. To increase game difficulty, the update frequency of this data (and of the orbital map) could be reduced to a value that fits one's tastes - once a minute, or so would be pretty challenging.

Anyway, returning to the point. While I think people ripping on MJ or its users because of "cheating" aren't justified at all, and if I'm not mistaken, manual control on the first manned spacecraft was added as a safety override over the default autopilot... (Actually, there is no way a human could accurately control a launch vehicle while under all that G-force...) I still think there are two reasons why I wouldn't count MJ as a "realism" mod.

One is that it removes the incentive to understand the basic mathematics involved in calculating delta-V, TWR, etc., which is, as others have pointed out, one of the main premises of the game, and improving upon this educational aspect is the main motivation of realism mods.

The other reason is that it's too convenient. Very XXI. century, if you will, or late 80s at best.

I haven't heard about kOS before, but I think I'll check it out. It sounds cool, and follows the idea of the game of being in control and having to understand the nuances that make up a successful space mission pretty well. Having to quickly code up a transfer burn on the autopilot console, and then trigger it the right moment, is very much what I'd expect of a game like KSP.

[Zad Fnark]

In my opinion, MechJeb doesn't represent a super autopilot. Rather it represents all the slide-rule using brainiacs back at Houston Mission Control providing navigation information to the Apollo missions and such.

Let's face it. The Astronauts on these missions were not calculating their burns by hand on the fly while in flight.

ZF-

[Zylark]

I'm a bit weary of the word 'realism' used in any game context. Usually it's just used as a semantic tool for somebody arguing some certain feature should be buffed or nerfed because that would be more 'realistic' whilst at the same time entirely glancing over that whatever game it is, there are plenty of features and mechanics that is much further away from any relationship with reality.

That said, MJ is a nice little approximation of how a manned spacecraft flight computer would do stuff - certainly simpler than the real deal, and being all-knowing it's data do not come with any margins of error. But since we don't have supercomputers to simulate flight operations before uploading an optimal flight-plan to the vessels autopilot, that is fine. It certainly reduces the tedium of routine operations, and all the data panels both in flight and in the VAB is really helpful.

For unmanned probes however, kOS is probably more apt as a flight-computer. Especially in tandem with RemoteTech. Probe computers tend to be simple things in order to save weight, power and make them rugged enough to withstand the temperatures and radiation of space. So manual programming like in kOS isn't entirely far off how it is actually done. Though I assume mission control auto-generate most code from more high-level GUI based tools, rather than only using a Command Line Interface. Then again, a CLI only approach would probably have prevented the Feet/Meters SNAFU of the Mars Climate Orbiter

[dreadicon]

Someone once pointed out that if you are using career mode/science mode, Mechjeb functionality only becomes available at points where you likely have already performed the maneuvers reliably yourself a few (or more than a few) times. It also gives a reason to buy the silly probe nodes, which otherwise are pointless besides form factor. Realistic? yes. Easier? Also yes.

But for me, it comes down to designing the nodes and tedium reduction. Without Mechjeb, I could do all the same orbital transfers, rendezvous, and orbital insertions it does; I know how to do the math, how to find dV, Isp, TWR, etc. But I have a job, and a wife, and friends, and plenty of other cool mechanics, math, and physics to learn rather than doing the calculations for these by hand after the first 4 or 5 times. IMHO, Mechjeb is like a calculator; an excellent tool in which there is no shame in using it, provided you know how to do what it does yourself.

Moreover, it still doesnt work so well with FAR; especially airplanes/spaceplanes