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What people call transversal velocity is actually angular velocity
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Jill Xelitras
Xeltec services
#81 - 2013-07-18 13:54:10 UTC
Tippia wrote:
Jill Xelitras wrote:
.... also: what about the coriolis effect ? Shouldn't projectile and hybrid turrets have a slight delay or inaccuracy in firing / hitting targets compared to laser turrets every time there is a change in angular speed ?
Weeeell… Coriolis applies to when both you (and the target) are locked in a different (rotating) frame of reference than the projectile is. What tracking does is pretty much the opposite of that: it ensures that the turret isn't locked in that frame of reference, and the tracking is all about compensating for the target's movement from the point of view of a neutral reference frame.

Or, to borrow a phrase from that article: “The Coriolis effect exists only when one uses a rotating reference frame.” The whole point is that turrets don't use a rotating reference frame.


Oh, wait ... now it makes sense:


  • ship A is stationary, ship B orbits ship A in a clockwise movement.
  • ship A's turrets have to turn clockwise to keep tracking ship B.
  • ship B itself turns counter-clockwise at the same angular velocity as ship A's turrets (assuming a perfect round orbit at constant speed)


Now in real life, the turrets of ship B would move at the same angular velocity as ship B (inherit movement from ship B).
But in eve, the turrets don't inherit the angular movement from the ship and therefore have an angular velocity equal to that of ship A's turret.

Is that what you are saying ?

Don't anger the forum gods.

ISD Buldath:

> I Saw, I came, I Frowned, I locked, I posted, and I left.
Jill Xelitras
Xeltec services
#82 - 2013-07-18 13:57:45 UTC
Weiz'mir wrote:

The cow-boy near his caravan will face tracking issues to shot me if my horse is fast enough. BUT ME, with my rifle, ridding my horse orbiting the caravan, do you really think that I will have any tracking issue ??


Most certainly, because on the horse you also get an up and down movement for which you have to compensate aswell. Big smileLolLol

Don't anger the forum gods.

ISD Buldath:

> I Saw, I came, I Frowned, I locked, I posted, and I left.
Tippia
Sunshine and Lollipops
#83 - 2013-07-18 14:04:33 UTC
Jill Xelitras wrote:
Now in real life, the turrets of ship B would move at the same angular velocity as ship B (inherit movement from ship B).
But in eve, the turrets don't inherit the angular movement from the ship and therefore have an angular velocity equal to that of ship A's turret.

Is that what you are saying ?

Yes.

I'm also saying that, in real life, we have plenty of devices and mechanisms that operate exactly like that so it's not something special or magical going on. Gimbals and gyroscopes have cancelled out external angular changes for many many (many) years now.

The only difference is that in real life, we also have gimbal locks, but since you'd still have to compensate for inaccuracies in your orbit, it's questionable whether you'd want to engage those in a fight anyway…
Jill Xelitras
Xeltec services
#84 - 2013-07-18 14:20:01 UTC
Tippia wrote:

I'm also saying that, in real life, we have plenty of devices and mechanisms that operate exactly like that so it's not something special or magical going on. Gimbals and gyroscopes have cancelled out external angular changes for many many (many) years now.

The only difference is that in real life, we also have gimbal locks, but since you'd still have to compensate for inaccuracies in your orbit, it's questionable whether you'd want to engage those in a fight anyway…


Hmm, you're right. Modern tanks can keep their guns on target while the tank is moving across terrain ... would be rather stupid to go back to old tank design where the turret could only be fired accurately while the tank is stationary.

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Weiz'mir
Brutor Tribe
Minmatar Republic
#85 - 2013-07-18 14:32:47 UTC
Jill Xelitras wrote:
Tippia wrote:

I'm also saying that, in real life, we have plenty of devices and mechanisms that operate exactly like that so it's not something special or magical going on. Gimbals and gyroscopes have cancelled out external angular changes for many many (many) years now.

The only difference is that in real life, we also have gimbal locks, but since you'd still have to compensate for inaccuracies in your orbit, it's questionable whether you'd want to engage those in a fight anyway…


Hmm, you're right. Modern tanks can keep their guns on target while the tank is moving across terrain ... would be rather stupid to go back to old tank design where the turret could only be fired accurately while the tank is stationary.


Same exemple as the one with me dressed up as an indian on a horse. Should the tank run around the target, the gun doesn't have to move...
Tippia
Sunshine and Lollipops
#86 - 2013-07-18 14:37:43 UTC
Weiz'mir wrote:
Same exemple as the one with me dressed up as an indian on a horse. Should the tank run around the target, the gun doesn't have to move...

Oh yes it does. Constantly. Otherwise, it would pretty much never be able to shoot — much less reliably hit — anything without coming to a stand-still. The difference in accuracy between a stabilised and a locked turret is immense.
Jill Xelitras
Xeltec services
#87 - 2013-07-18 14:37:48 UTC  |  Edited by: Jill Xelitras
Weiz'mir wrote:

Same exemple as the one with me dressed up as an indian on a horse. Should the tank run around the target, the gun doesn't have to move...


Yes, but RL is not EVE.

edit:

To add to Tippia's post above. What she said is true because the tank will always be subjected to some random movement. The tank will never be able to move around in a 100% constant angular movement. It will be shaking like a video taken on your smartphone. That's why steady cam was invented. Steady cam moves the camera in the opposite direction of what you are doing at the exact same speed and angle to keep the camera steady.

In a perfect lab experiment, and assuming that the turrets would both behave according to RL physics (not eve physics) and were glued in a fix position on the ship, then you would be right.

But my money is on Tippia.

Don't anger the forum gods.

ISD Buldath:

> I Saw, I came, I Frowned, I locked, I posted, and I left.
Weiz'mir
Brutor Tribe
Minmatar Republic
#88 - 2013-07-18 14:43:18 UTC
Jill Xelitras wrote:

Yes, but RL is not EVE.


oh wait...
Weiz'mir
Brutor Tribe
Minmatar Republic
#89 - 2013-07-18 18:05:09 UTC
Jill Xelitras wrote:

To add to Tippia's post above. What she said is true because the tank will always be subjected to some random movement. The tank will never be able to move around in a 100% constant angular movement.


No. That's absolutely not what she is saying.
Jill Xelitras
Xeltec services
#90 - 2013-07-18 18:13:56 UTC
Weiz'mir wrote:
Jill Xelitras wrote:

To add to Tippia's post above. What she said is true because the tank will always be subjected to some random movement. The tank will never be able to move around in a 100% constant angular movement.


No. That's absolutely not what she is saying.


Oh, yes it is.

Tippia wrote:
The difference in accuracy between a stabilised and a locked turret is immense.



Don't anger the forum gods.

ISD Buldath:

> I Saw, I came, I Frowned, I locked, I posted, and I left.
Weiz'mir
Brutor Tribe
Minmatar Republic
#91 - 2013-07-19 10:59:33 UTC
Jill Xelitras wrote:
Weiz'mir wrote:
Jill Xelitras wrote:

To add to Tippia's post above. What she said is true because the tank will always be subjected to some random movement. The tank will never be able to move around in a 100% constant angular movement.


No. That's absolutely not what she is saying.


Oh, yes it is.

Tippia wrote:
The difference in accuracy between a stabilised and a locked turret is immense.





You did'nt understand her point. She was talking about turrets gyro-stabilized that need to track a still target (notwithstanding any alea or random movement).

And I doubt that Tippia would agree with you (and me) when you write :

Jill Xelitras wrote:

In a perfect lab experiment, and assuming that the turrets would both behave according to RL physics (not eve physics) and were glued in a fix position on the ship, then you would be right.


Tippia
Sunshine and Lollipops
#92 - 2013-07-19 11:23:26 UTC
Weiz'mir wrote:
You did'nt understand her point.
Yes he did. You did not.

The larger point is that, from the EVE ship perspective, if you're going to move your turret around anyway, why create a lock-down mechanism that the tracking then has to fight when you could just decouple the tracking from the ship movement entirely and let it do its own thing. There's no reason to enforce a gimbal lock other than to stow the guns for travel. End result: turrets that sit within their own reference frame and have to track the target from that point of view rather than the PoV of the ship.
Tiber Ibis
The Paratwa Ka
#93 - 2013-07-19 11:27:37 UTC
This is kind of a ridiculous argument. Does anyone actually have evidence to suggest whether turrets would operate with a freely rotational pivot independent of the ship, or whether they would be attached to the ship and operate dependent on the ships movement. I would say the later is more likely, although as there are no real examples of turrets mounted on real space ships then I would assume that both variations are possible.
Tippia
Sunshine and Lollipops
#94 - 2013-07-19 11:29:40 UTC
Tiber Ibis wrote:
Does anyone actually have evidence to suggest whether turrets would operate with a freely rotational pivot independent of the ship
…ehm… that's exactly how turrets in EVE work (for the simple reason that ships don't really have any kind of rotation to inherit, what with being points and all).
Tiber Ibis
The Paratwa Ka
#95 - 2013-07-19 11:53:54 UTC
Tippia wrote:
Tiber Ibis wrote:
Does anyone actually have evidence to suggest whether turrets would operate with a freely rotational pivot independent of the ship
…ehm… that's exactly how turrets in EVE work (for the simple reason that ships don't really have any kind of rotation to inherit, what with being points and all).

I know that is how turrets work in eve. But seeing as the suggestion was that turrets would not work like this in real life, I was simply stating we don't actually know how turrets would work in real life, and they could in fact work both ways.
Infinity Ziona
Sebiestor Tribe
Minmatar Republic
#96 - 2013-07-19 12:25:54 UTC  |  Edited by: Infinity Ziona
Tippia wrote:
Weiz'mir wrote:
You did'nt understand her point.
Yes he did. You did not.

The larger point is that, from the EVE ship perspective, if you're going to move your turret around anyway, why create a lock-down mechanism that the tracking then has to fight when you could just decouple the tracking from the ship movement entirely and let it do its own thing. There's no reason to enforce a gimbal lock other than to stow the guns for travel. End result: turrets that sit within their own reference frame and have to track the target from that point of view rather than the PoV of the ship.

Good god. Whether its locked or able to track makes no difference. Even a tracking turret wouldn't have to track when mounted on a hull that is in a orbit around a stationary target in any realistic situation.

Imagine the space shuttle orbiting the earth with a gun pointed 90 degrees towards the earth. It would be guaranteed to hit the earth no matter what.

Imagine a clock is a stationary ship, it's hands are the direction from which a turret is firing at it from the end points in. Cut out a firing paper ship and blue tack it to the ends of the hands.

The only inaccuracies you will get are when the target is small and the velocity of the ship imparted to the projectile as it leaves the gun cause it to miss which would not happen given the velocities of rounds vs speed of eve ships. Even then the tracking to compensate would be tiny.

CCP Fozzie “We can see how much money people are making in nullsec and it is, a gigantic amount, a shit-ton… in null sec anomalies. “*

Kaalrus pwned..... :)
Weiz'mir
Brutor Tribe
Minmatar Republic
#97 - 2013-07-19 12:31:57 UTC  |  Edited by: Weiz'mir
Tippia wrote:
Weiz'mir wrote:
You did'nt understand her point.
Yes he did. You did not.


Great news ! Because he considers that a perfectly orbiting ship wouldn't suffer any tracking issue :

Jill Xelitras wrote:


In a perfect lab experiment, and assuming that the turrets would both behave according to RL physics (not eve physics) and were glued in a fix position on the ship, then you would be right.


Big smile
Weiz'mir
Brutor Tribe
Minmatar Republic
#98 - 2013-07-19 12:39:27 UTC  |  Edited by: Weiz'mir
Infinity Ziona wrote:

Good god. Whether its locked or able to track makes no difference. Even a tracking turret wouldn't have to track when mounted on a hull that is in a orbit around a stationary target in any realistic situation.


+1

(Tippia will disagree ;
Jill Xelitras will agree but give his money to Tippia;
Tippia will agree with Jill Xelitras but says the opposite ;
etc. etc.)

Anyone to close the topic ?
Infinity Ziona
Sebiestor Tribe
Minmatar Republic
#99 - 2013-07-19 12:41:37 UTC
Tiber Ibis wrote:
Tippia wrote:
Tiber Ibis wrote:
Does anyone actually have evidence to suggest whether turrets would operate with a freely rotational pivot independent of the ship
…ehm… that's exactly how turrets in EVE work (for the simple reason that ships don't really have any kind of rotation to inherit, what with being points and all).

I know that is how turrets work in eve. But seeing as the suggestion was that turrets would not work like this in real life, I was simply stating we don't actually know how turrets would work in real life, and they could in fact work both ways.

We do know how turrets work in real life. Given there is no flight time for gun rounds in EvE we also know how turrets would work in EvE if they were real life. If its pointing at something and fires, it hits.

CCP Fozzie “We can see how much money people are making in nullsec and it is, a gigantic amount, a shit-ton… in null sec anomalies. “*

Kaalrus pwned..... :)
Ciyrine
Deep Core Mining Inc.
Caldari State
#100 - 2013-07-19 13:41:53 UTC
Tippia wrote:
The more accurate illustration is that, if you are a director shooting a cowboy movie and want to do a 360° dolly shot around the caravan using a gyro-stabilised camera, then you will have to keep turning that camera because it will not rotate along with the dolly. If you don't, the camera will capture a whole lot of terrain rather than the mug of your overpaid star actor.


Turrets(like on a battleship) are attached to the hull for a reason. Because every time they fire they would start spinning crazily from the recoil(the conventional ones). And every time a space particle bumps into them they would get bumped off course. At 4km/s that would happen a lot around the celestial bodies we do combat.

But more damning of all is how would a turret rotate if its not attached to the hull? if its just gyrostabilized and free floating in space effectively then it would need to have its own engines to rotate since it wouldnt be able to use the hull to rotate off of with a turning device of some sort.

In your camera gyrostabilzed example. If the human just holds the camera and doesnt rotate his hands/camera he will stay on target....ONLY if the human isnt present would the camera stray off target. the human in terms of an eve turret would be the rotation mechanism attached to both turret/hull that provides the tracking/rotation capability.

Without that mechanism youd have to attach thrusters to the guns