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Does anybody know, mathematically speaking what effect the length of the ship has on its ability to turn?
If I want to compare the spin ratio of a ship, it does not seem adequate just to divide the spin torque by the mass of the ship. The mass clearly has an effect on the speed at which a ship spins but i'm wondering mathematically what effect length has and how you could express it in a ratio using the stats that we are given about each ship for comparative purposes.
If I want to compare the spin ratio of a ship, it does not seem adequate just to divide the spin torque by the mass of the ship. The mass clearly has an effect on the speed at which a ship spins but i'm wondering mathematically what effect length has and how you could express it in a ratio using the stats that we are given about each ship for comparative purposes.
/me smells a plugin
Qualitatively speaking (if mass is evenly distributed), the longer the ship, the more rotational inertia it will have. You might also try looking up the moment of inertia of a rod (to simplify).
As a thought experiment: imagine an ice skater spinning about her axis with her arms extended. As she pulls her arms in, the rate at which she spins increases because her moment of inertia decreases, and momentum is conserved. Mass has not changed.*
Mathematically (thinking back to second semester of freshman mechanics), it gets a bit intense.
*(more accurately: the total mass of the system hasn't changed)
As a thought experiment: imagine an ice skater spinning about her axis with her arms extended. As she pulls her arms in, the rate at which she spins increases because her moment of inertia decreases, and momentum is conserved. Mass has not changed.*
Mathematically (thinking back to second semester of freshman mechanics), it gets a bit intense.
*(more accurately: the total mass of the system hasn't changed)
yeah but the devs must use a formula to calculate it. The thing is it doesn't have to be accurate in a semantic physics sense, or even in a gameplay sense because its for comparative purposes. It just needs to be something that we can apply to the length statistic that comes with every ship so you can get an idea of how maneuverable one is compared to another.
Qualitatively speaking (if mass is evenly distributed), the longer the ship, the more rotational inertia it will have. You might also try looking up the moment of inertia of a rod (to simplify).
Or: why the Raptor turns like a Hornet. They're both 17m long.
Or: why the Raptor turns like a Hornet. They're both 17m long.
Just to give you a touch of help the turn rate is capped like many of the other stats.....
Yeah, the rate is, and it's the same for most ships. How quickly they accelerate up to that speed is what differentiates them.
Spin torque / length : Mass ratio?
1) "Length" in the description is a value defined by hand and is not an accurate depiction of actual object length.
2) The game calculates the moment of inertia based on an even distribution of mass within respective geometry. So object geometry (specifically, the OBB/collision geometry) is a factor in handling. Thus, "length" is not a trivially helpful definition: a barbell-type object will behave differently from a central-sphere with a thin rod through it, assuming both rotate from the center point, have the same total mass and the same overall "length" along their longest axis.
2) The game calculates the moment of inertia based on an even distribution of mass within respective geometry. So object geometry (specifically, the OBB/collision geometry) is a factor in handling. Thus, "length" is not a trivially helpful definition: a barbell-type object will behave differently from a central-sphere with a thin rod through it, assuming both rotate from the center point, have the same total mass and the same overall "length" along their longest axis.
1) This is all I needed to know, if you define length by hand it doesn't play a role in determining manuverability and thus it's useless as a comparative statistic.
2) This appears to debunk the myth that adding a weapon that weighs more on one side than on another will make your ship 'lop-sided' when it comes to maneuverability if it does in fact distribute the mass evenly. Interesting stuff.
2) This appears to debunk the myth that adding a weapon that weighs more on one side than on another will make your ship 'lop-sided' when it comes to maneuverability if it does in fact distribute the mass evenly. Interesting stuff.
2) This appears to debunk the myth that adding a weapon that weighs more on one side than on another will make your ship 'lop-sided' when it comes to maneuverability if it does in fact distribute the mass evenly. Interesting stuff.
Yes, any mass added to a vessel is just added uniformly. We don't factor in the addon port locations or relative mass induced on the respective location or anything.
Yes, any mass added to a vessel is just added uniformly. We don't factor in the addon port locations or relative mass induced on the respective location or anything.
While i've got your attention and on the chance that you come back to this thread, i'd love to get your views just quickly on these ratios for comparing ships based on their visible stats in station:
Thrust/Weight Ratios
Cruise: thrust / mass (Manuverability)
Turbo: turbo thrust / mass (Acceleration)
Must figure out how to factor in max cruise speed here
Spin ratio
spin torque / mass
Armour to maneuverability ratio
Armour * (thrust / mass)
Armour to mass
armour / mass
Turbo distance after acceleration
(1 / turbo energy) * turbo max speed
Can you (or anyone else for that matter) think of any other ratios that could be used to compare the performance of ships based on the visible stats?
And most importantly, are any more of those stats contrived/trivial when it comes to actual gameplay effect
Thrust/Weight Ratios
Cruise: thrust / mass (Manuverability)
Turbo: turbo thrust / mass (Acceleration)
Must figure out how to factor in max cruise speed here
Spin ratio
spin torque / mass
Armour to maneuverability ratio
Armour * (thrust / mass)
Armour to mass
armour / mass
Turbo distance after acceleration
(1 / turbo energy) * turbo max speed
Can you (or anyone else for that matter) think of any other ratios that could be used to compare the performance of ships based on the visible stats?
And most importantly, are any more of those stats contrived/trivial when it comes to actual gameplay effect
None of those stats are contrived, they're all "real-world". As to their respective value.. that's a lot bigger discussion. My earlier post would explain why "Spin ratio" is not that meaningful, as it doesn't factor in the geometry of the object.
Yeah I mean we discovered that when you told us to go try out the new vulture and it spun around slower than the older one.
Would there be any way for you to generate a statistic that considers the dimensions of the model and display those in the station for comparative purposes or is that in the realm of 'non-trivial development'?
I feel like we're missing out on some of the cool tools that other mmo's get to compare different ships and loadouts. I am trying to rectify this but its proving a more difficult task than I anticipated.
Would there be any way for you to generate a statistic that considers the dimensions of the model and display those in the station for comparative purposes or is that in the realm of 'non-trivial development'?
I feel like we're missing out on some of the cool tools that other mmo's get to compare different ships and loadouts. I am trying to rectify this but its proving a more difficult task than I anticipated.
Would there be any way for you to generate a statistic that considers the dimensions of the model and display those in the station for comparative purposes or is that in the realm of 'non-trivial development'?
It's possible, yeah. There could be some kind of simple "turn acceleration" value or something, and maybe contorted into a "maneuverability factor" using the current ship-mass and whatnot.
But definitely not this month, or perhaps even this year (unless someone has some time open up). The whole persistency development, and various other things, have us rather backed-up and under the gun.
It's possible, yeah. There could be some kind of simple "turn acceleration" value or something, and maybe contorted into a "maneuverability factor" using the current ship-mass and whatnot.
But definitely not this month, or perhaps even this year (unless someone has some time open up). The whole persistency development, and various other things, have us rather backed-up and under the gun.
I wouldn't want it to take priority over, you know, interesting stuff.
Even so, the spin torque per KG of mass actually does seem to pass the pub test on first glance, here it is with a small selection of ships:
I thought it was weird that the vultures 1-3 turned faster than the centurions 1-3, but just trying both out in the same manner that I compared the vulture IV to the SANE edition it feels like the chart is fairly correct in that regard.
So I don't know, i'll probably keep it around until you come up with something better and just make a note that it depends on the specifics of the mesh. I am sad that we don't have more accurate comparative metrics wrt turn-ability of ships though.
:(
Even so, the spin torque per KG of mass actually does seem to pass the pub test on first glance, here it is with a small selection of ships:
I thought it was weird that the vultures 1-3 turned faster than the centurions 1-3, but just trying both out in the same manner that I compared the vulture IV to the SANE edition it feels like the chart is fairly correct in that regard.
So I don't know, i'll probably keep it around until you come up with something better and just make a note that it depends on the specifics of the mesh. I am sad that we don't have more accurate comparative metrics wrt turn-ability of ships though.
:(
What is it with you and graphs?
Even so, the spin torque per KG of mass actually does seem to pass the pub test on first glance
That's fine.. I'm just saying correlation isn't causation. It's a meaningful comparison within a given ship type (model), but across different models you get into the distribution problem. I could have a worse ratio, but a better turn acceleration, using a denser spherical object profile.
That's fine.. I'm just saying correlation isn't causation. It's a meaningful comparison within a given ship type (model), but across different models you get into the distribution problem. I could have a worse ratio, but a better turn acceleration, using a denser spherical object profile.
1) "Length" in the description is a value defined by hand and is not an accurate depiction of actual object length.
How exactly does the "Length" stat get factored in to all this though? The Centaur MkIII (16m) seems to turn quicker than the Tunguska Centaur Aggresso (18m) even though the Aggresso has the exact same mass:torque ratio (1000kg/N)
How exactly does the "Length" stat get factored in to all this though? The Centaur MkIII (16m) seems to turn quicker than the Tunguska Centaur Aggresso (18m) even though the Aggresso has the exact same mass:torque ratio (1000kg/N)
How exactly does the "Length" stat get factored in to all this though? The Centaur MkIII (16m) seems to turn quicker than the Tunguska Centaur Aggresso (18m) even though the Aggresso has the exact same mass:torque ratio (1000kg/N)
It.. doesn't. It's an arbitrary number that is displayed for window-dressing reasons.
The actual length of the ship does have an impact, as it's a factor in the actual distribution of mass throughout the ship (mass is evenly distributed, but within the respective geometry).
Objects with more mass at their ends will have slower turning-acceleration, due to physics. See barbell-vs-sphere analogy above. All things being equal, longer objects will be slower to turn.
It.. doesn't. It's an arbitrary number that is displayed for window-dressing reasons.
The actual length of the ship does have an impact, as it's a factor in the actual distribution of mass throughout the ship (mass is evenly distributed, but within the respective geometry).
Objects with more mass at their ends will have slower turning-acceleration, due to physics. See barbell-vs-sphere analogy above. All things being equal, longer objects will be slower to turn.