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blankseplocked Transversal Velocity, real or something made up?
 
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Stovrose
Posted - 2007.08.24 07:22:00 - [1]
 

After studying different kinds of vectors and physics involving radians, spheres, velocities and accelerations, I have yet to come across anything that compares a relationship between two objects' direction and velocity in the way in which Eve's transversal velocity does. If you go and look at the tracking guide in the the Player Guide, it explains "The perpendicular vector from the line of sight to the spot where vector A (velocity and direction of Ship A) minus vector B (velocity and direction of Ship B) points to the transversal velocity between two ships." Shocked I can not figure out the equation to calculate such a thing on my own nor can I find it on the internet. What is the equation to calculate the vector Transversal Velocity?

Chribba
Otherworld Enterprises
Otherworld Empire
Posted - 2007.08.24 08:04:00 - [2]
 

A * B - (1/X^2) sq 333 + (0.05*5)/180 = Ore Yield.

Needo
Minmatar
Swedish Academy
Posted - 2007.08.24 08:12:00 - [3]
 

I'm no math wiz but it shouldnt be hard? Just make a coordinate system where z is the axis from ship a to ship b, then sum up the x-y components of the two ships speed vectors within this coordinate system.

MotherMoon
Huang Yinglong
Posted - 2007.08.24 08:17:00 - [4]
 

it's quite simple.
it's the speed that object A is moving in relation to object B.

if they are both moving in the same direction, at the same speed, to each other they are not moving at all.

turn on your angular velocity to see what the actual radius/sec is. and thus see if you can hit or not.

Sakura Nihil
Selective Pressure
Rote Kapelle
Posted - 2007.08.24 08:46:00 - [5]
 

Edited by: Sakura Nihil on 24/08/2007 08:47:27
Simple answer here.

Explained answer, your 3D velocity vector can be translated into a radial velocity, and a transversal velocity. Draw a mental line between point 1 (your ship) and point 2 (the other ship/object), and you can resolve your real velocity into a part that points straight towards or away from the target ship (the radial velocity), and another velocity vector that's at a right angle to that line between the two points.

In many ways, its like a triangle...

------
|.../
|../
|./
|/

You're at the bottom point of the triangle, and moving to the top-right, the hypotenuse of the triangle. The target ship is at the top left point of the triangle, so the radial velocity is the line from you to them (the left side), and your transversal velocity is the top side of the triangle. That's the gist of it Razz.

PS: I assumed a non-moving target btw. So, yea, not a complete idea of what's going on mind you Cool.

SteeleResolve
Amarr
The Fiction Factory
Precision Gears
Posted - 2007.08.24 08:47:00 - [6]
 

Originally by: MotherMoon
it's quite simple.
turn on your angular velocity to see what the actual radius/sec is. and thus see if you can hit or not.


That.

I don't understand why people use transversal. Angular velocity can be compared directly to your turret's tracking speed. Simple.

Cardassius
Seraphin Technologies
KrautbreaK
Posted - 2007.08.24 08:51:00 - [7]
 

Originally by: SteeleResolve
Originally by: MotherMoon
it's quite simple.
turn on your angular velocity to see what the actual radius/sec is. and thus see if you can hit or not.


That.

I don't understand why people use transversal. Angular velocity can be compared directly to your turret's tracking speed. Simple.


Transversal is what needs to be low in order to kill your enemy, it takes your movement and the enemies movement to determine if it's a hit :)

Sakura Nihil
Selective Pressure
Rote Kapelle
Posted - 2007.08.24 08:52:00 - [8]
 

Originally by: Cardassius
Originally by: SteeleResolve
Originally by: MotherMoon
it's quite simple.
turn on your angular velocity to see what the actual radius/sec is. and thus see if you can hit or not.


That.

I don't understand why people use transversal. Angular velocity can be compared directly to your turret's tracking speed. Simple.


Transversal is what needs to be low in order to kill your enemy, it takes your movement and the enemies movement to determine if it's a hit :)


I get what he's saying, why focus on transversal that doesn't take into account distance from target, when the angular velocity would and therefore be better used as an indicator that you can "pewpew" someone in the face? Cool

Brixer
Dai Dai Hai
Posted - 2007.08.24 08:54:00 - [9]
 

I usually orbit the astroid @ 15km, and have found that doing that in a MWDing hulk doesn't give any worse result on yield.. Laughing
So.... I think Schribba got something wrong in his formula there.. Unless that formula only apply to mining dreads.

On a serious note.. Orbiting in perfect circle around your target and firing with guns should give 0 rad/sec.. But that would upset so many Caldari crow pilots they just removed the *correct* formula.



Sakura Nihil
Selective Pressure
Rote Kapelle
Posted - 2007.08.24 08:57:00 - [10]
 

Originally by: Brixer
I usually orbit the astroid @ 15km, and have found that doing that in a MWDing hulk doesn't give any worse result on yield.. Laughing
So.... I think Schribba got something wrong in his formula there.. Unless that formula only apply to mining dreads.

On a serious note.. Orbiting in perfect circle around your target and firing with guns should give 0 rad/sec.. But that would upset so many Caldari crow pilots they just removed the *correct* formula.



Remember, realism isn't good for games sometimes Wink.

Think Crows and Vagas are overpowered now? If it was made so transversal wasn't mutual, interceptors and Vagas and nanoships could do full damage, MWD on, sooooo... yes. Go go game mechanics in this matter Razz.

vanBuskirk
Caldari
Posted - 2007.08.24 08:59:00 - [11]
 

Edited by: vanBuskirk on 24/08/2007 09:02:51
Transversal velocity is simply the velocity across the line of sight. For purposes of tracking, motion towards or away from your ship is irrelevant. Note that velocity is relative; so that if you and the target ship are both travelling in the same direction at the same speed then the velocity should be listed as 0.

To amplify; velocity is a vector, and in space it's 3D and can be represented by 3 components, call them directions X, Y and Z. If the Z direction is the one in a direct line between you and the target, then the component of the velocity in that direction is irrelevant to targeting.

In actual fact, what is important is not transversal velocity (which includes the direction in which it's going across your line of sight) but transversal speed; for purposes of targeting the direction is irrelevant.

What is important is the distance between target and you. This is because what is really important for tracking is angular speed. The formula for this is quite simple; angular speed in radians per second is transverse speed in meters per second divided by distance away in metres. If angular speed is higher than your guns' tracking then they won't track and you will most likely miss.

Incidentally, angular velocity is again a vector, this time two-dimensional. However, what is important is its magnitude, not its direction.

Personally, I leave the display of transverse velocity turned off; it doesn't help at all to find out whether guns will hit or not. The angular velocity display does. Total velocity display also matters, but only if you're using missiles.

I think that the velocity displays are relative to your ship, but I could easily be wrong.

I hope I've cleared things up a bit. It doesn't help that the game often uses "velocity" where "speed" would be more appropriate. I would like to see the tactical overlay having an option to show "velocity trails" for at least targeted ships so you could manouvre to minimise transversal. Maybe in Revs 3. Smile

Akita T
Caldari Navy Volunteer Task Force
Posted - 2007.08.24 09:04:00 - [12]
 

Originally by: Stovrose
I have yet to come across anything that compares a relationship between two objects' direction and velocity in the way in which Eve's transversal velocity does.
[...]
I can not figure out the equation to calculate such a thing on my own nor can I find it on the internet.
What is the equation to calculate the vector Transversal Velocity?


First off "transversal velocity" is an imaginary velocity with no physical meaning (in the real world anyway).
It actually has no meaning in EVE either, short of being a fictional factor in the "to hit" formula for turrets.
And I say "fictional" because it's simply the product between the angular velocity (or whatever you like to call it) of the enemy ship and the distance between you and the target.
The tracking formula has a transversal*distance factor inside, which is, what a surprise, the angular velocity.

This "angular velocity" (not sure if it's the proper term) is simply the variation speed of the (volumetric) angle the enemy ship makes with the point in which your ship is.
Mark the "point in which your ship is" part. It's important.
And it's important because it means your ship's rotation/movement is IRRELEVANT, and two ships (regardless of trajectory) always have the same absolute angular velocity (and therefore fictional "transversal velocity") with regards to eachother.

The only relevant physical model that could have this "absolute angular velocity" as a relevant value would be if all your guns would have been mounted on gyroscopes, so that all your turrets always stay oriented in the same direction (with regards to "space") normally.
Then indeed, in this situation, the absolute angular velocity you see in EVE has a meaning, and it's the actual angular velocity you have to apply to your guns (that are already mounted on gyroscopes) with respect to the gyroscope mount to track the intended target.


Now, here's where the analogy breaks in the "to hit" formula.
It would be all nice and dandy if that would be all about actual tracking... but no, for some reason, we also have two extra values : gun signature resolution, and target signature radius.
Now, for SOME reason, your guns' tracking value is multiplied by the ratio of target signature over gun signature, instead of having separate failure chances depending on them.
So, basically, for an unnamed reason, it's as if your turrets have trouble rotating when pointed at a small target, yet rotate quite nicely when pointed at a "normal size" target, and go into overdrive whwnever pointing at a much larger object.
___

Oh, and welcome to the crazy world of "EVE science"... a special branch of math/physics/whatever that only applies to the EVE universe.
From the following episode next week : missile explosion velocity, explosion radius, and AoEFalloff.

Cpt Branko
Retired Pirate Club
Posted - 2007.08.24 09:14:00 - [13]
 

Transversal velocity is a useless piece of information, anyway. The thing you want to know is angular velocity, measured in rad/sec, the same units used to express gun tracking.

Vincenzo Delloro
Amarr
Lux et Veritas
Posted - 2007.08.24 09:40:00 - [14]
 

I was told there would be no math.

Stitcher
Caldari
Posted - 2007.08.24 09:45:00 - [15]
 

Originally by: Vincenzo Delloro
I was told there would be no math.


I just eyeball it, tbh. no maths, just "I reckon I can hit that" and "Don't think I can get that one."

Agor Dirdonen
Posted - 2007.08.24 11:10:00 - [16]
 

Edited by: Agor Dirdonen on 24/08/2007 11:11:13
Originally by: Cpt Branko
Transversal velocity is a useless piece of information, anyway. The thing you want to know is angular velocity, measured in rad/sec, the same units used to express gun tracking.


It's not useless, it gives you information on how the other guy is moving relative to you. It's not all about knowing when to hit. It's also about knowing how the other guy is moving around. Velocity combined with transversal speed gives you a good idea if the guy is moving towards you or more perpendicular.

If Transversal is close to the velocity, he's not getting closer. You can get this from angular velocity as well but it's less clear. Same for looking at how the distance is changing: if you want to react fast to an enemy getting closer and you only pay attention to the distance getting smaller fast suddenly, you already lost valuable time to react. Using Velocity/Transversal gives you this info immediately.

I'm not saying angular velocity is useless, I'm just saying transversal isn't either Very Happy .

Iyanah
Minmatar
Tuikoax
Posted - 2007.08.24 11:51:00 - [17]
 

Originally by: Stovrose
After studying different kinds of vectors and physics involving radians, spheres, velocities and accelerations, I have yet to come across anything that compares a relationship between two objects' direction and velocity in the way in which Eve's transversal velocity does. If you go and look at the tracking guide in the the Player Guide, it explains "The perpendicular vector from the line of sight to the spot where vector A (velocity and direction of Ship A) minus vector B (velocity and direction of Ship B) points to the transversal velocity between two ships." Shocked I can not figure out the equation to calculate such a thing on my own nor can I find it on the internet. What is the equation to calculate the vector Transversal Velocity?


transversal velocity is something like the radial velocity.

consider the target ship as a point on the circumference of a circle, transversal velocity is how fast that point navigates along the circumference. this can be compared to the tracking speed of a turret - which is how fast the turret can rotate on it's mountings.

Swamp Ziro
Ultimate Betrayal.
Vera Cruz Alliance
Posted - 2007.08.24 12:44:00 - [18]
 

Edited by: Swamp Ziro on 24/08/2007 12:44:52
Originally by: Sakura Nihil
Originally by: Cardassius
Originally by: SteeleResolve
Originally by: MotherMoon
it's quite simple.
turn on your angular velocity to see what the actual radius/sec is. and thus see if you can hit or not.


That.

I don't understand why people use transversal. Angular velocity can be compared directly to your turret's tracking speed. Simple.


Transversal is what needs to be low in order to kill your enemy, it takes your movement and the enemies movement to determine if it's a hit :)


I get what he's saying, why focus on transversal that doesn't take into account distance from target, when the angular velocity would and therefore be better used as an indicator that you can "pewpew" someone in the face? Cool


Transversal is a more useful stat to have on your overview.

Because transversal has some advantages over raw angular velocity. Tho the latter can be directly compared to your tracking, this is often a calculation that most pilots can do subconciously out of experience, and not that important..

However transversal velocity also gives you a real m/s speed count that can also tell you a lot about what kind of fit (nano or not, mwd or no) the enemy is using, and a rough estimate about how fast he can go. Especially if you're not moving yourself.


For example, I'm standing still, and I see a BC with transversal 250. I instantly know that it's a nanoship with overdrives on. See? :D


 

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