What makes the engine gimbal?

[Brotoro]

Surely they just pull a little extra angular momentum off of the reaction wheels to do the gimbaling. Why have more that one source of Magic Torqueâ„¢ onboard?

[Reactordrone]

I assume it's a fueldraulic system or other gas pressurised tank system.

[322997am]

Magic torqueâ„¢ is powered by electrical charge which the craft might not have

[T-Bouw]

Hydraulics.

But what powers the hydraulics? Who knows.

The same thing that makes your car brake when the engine isn't running.

You have a master-cylinder for each axis in the cockpit which actuates the cylinders in the gimbal.

[Wemb]

Fly by wire - or in Kerbin's case, more likely string.

[Unheld]

Well, hang on a minute. All these answers are just wrong.

Everybody can see that the gimbals gimbal instantaneously from zero to max_gimbal_angle without gimbaling through the angels in between and therefore it must be QUANTUM!!

[Guest]

42. Or, cause this is the Kerbal universe, korty-kwo.

[problemecium]

The way I see it, "ElectricCharge" as shown on the meter only means high-power electric charge as would be used by machinery such as giant reaction wheels or long-range antennae. Being out of it means that you can't run those things, but doesn't actually mean no electrical power exists on the ship, as evidenced by the fact that batteries can still be switched on and off, battery LEDs remain on, and Kerbals can operate the throttle and gimbal controls. There just isn't sufficient power to run the big stuff.

[mikegarrison]

Well, hang on a minute. All these answers are just wrong.

Everybody can see that the gimbals gimbal instantaneously from zero to max_gimbal_angle without gimbaling through the angels in between and therefore it must be QUANTUM!!

Did you just say that angels gimbal the engines?

- - - Updated - - -

Angels...

Ah ha! Another vote for angels.

[totos_totidis]

It could be the kraken.

It is used to gimbal the engines but when it gets mad it ruins the ships it is supposed to help.

[Armchair Rocket Scientist]

For pump-fed engines, hydraulics driven by the engine's turbopump. It's just that nobody bothered to code having the gimbal stop working when the engine is turned off. The pressure-fed engines, like the LV-1R, the 24-77, and maybe the MK-55, probably have an electrical gimbal (or electrically-powered hydraulics for the MK-55 assuming it isn't pump-fed.

[nigelvn]

obviously a Kraken who takes control over the ship when the batteries are dead

[Daveroski]

Kerbals are green. Brussels Sprouts are green. Kerbals (Quite Rightly) hate the taste of Brussels Sprouts and so the more you eat the more heroic you are.

All our kerbals (Even the terrified ones) are truly heroic and indulge in this eating of the sprouts before every launch.

All that gas and energy has to go somewhere.

So when you see the gimble shaking like a mad thing. Give a thought to the Brave Kerbals who go through so much to be heroes.

[ouion]

Hydraulics- Using pressure pumps and levers to nudge the engine to the correct position

Fly by system- Similar to planes that use electronics to turn the rudder and flaps.

[RyanRising]

The way I see it, "ElectricCharge" as shown on the meter only means high-power electric charge as would be used by machinery such as giant reaction wheels or long-range antennae. Being out of it means that you can't run those things, but doesn't actually mean no electrical power exists on the ship, as evidenced by the fact that batteries can still be switched on and off, battery LEDs remain on, and Kerbals can operate the throttle and gimbal controls. There just isn't sufficient power to run the big stuff.

Not enough power to run the RPM monitors though, as I am reminded of whenever I forget solar panels.

[Beowolf]

It's the slithy toves that make the engine gyre and gimble in the wabe.

Winner!

[Falconer]

They should rename this game "Hamster Space Program"

Only if they're of the Miniature Giant Space variety......

Of all the mods... I've yet to see a Spelljammer one.....

[Rath]

Compressed air (kerbal farts)

[RocketBlam]

Little known fact, every gimballed engine has a kerbal installed in it, who can move the engine around with his little Kerbal hands, and gets very hot.

[Felsmak]

Sounds like this is where one would like to have a myriad of interns onboard, cranking and churning.

Like a space trireme, sort of?

[Wjolcz]

Eh. I came here to actually find out what makes them move IRL. Was a bit dissapointed.

I'm just going to assume it's some servos. Or short range teleporting abilities.

[Starwhip]

Well, hang on a minute. All these answers are just wrong.

Everybody can see that the gimbals gimbal instantaneously from zero to max_gimbal_angle without gimbaling through the angels in between and therefore it must be QUANTUM!!

Angels + Quantum = Weeping Angels.

[Guest]

Clearly engine gimbaling is the result of a system of ropes and pulleys, held together with struts, and post-it notes.

[SciMan]

Gimbals use power assisted hydraulics, just like a car's brakes.

On a gas/petrol powered car, the engine's manifold vacuum is used to assist the driver's foot in applying pressure to the brake master cylinder's piston.

On a rocket in KSP, the ship's electric charge is used to assist the pilot's hands applying pressure to the control stick.

In both cases, manual control is still present if power is unavailable.

Of course, the engines gimbal will always overshoot because the Kerbal or probe core controlling it expects manual controls, but the assisted controls require far less force.

This explains how gimbals work in KSP (without breaking immersion), why they always go instantly to their limits, AND why the attitude hold SAS modes cause so much wobble.

Aerodynamic control surfaces, RCS, and reaction wheels are all tied into the same controls as engine gimbals, so they all have the same overshoot problem.

They all react at different speeds, so they cause more/less wobble depending on type.

Edited July 7, 2015 by SciMan