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Veld

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1 hour ago, Veld said:

What we know from our gravity analysis

  • Judging by the velocities and fuel time of the spacecraft in the videos, the delta-v supplied by the specific impulse must be huge. So huge it is plausible to simply make for the moon in a perfectly straight line. It is also important to note the planet, alioth, and its moon a very small in relation to our earth/moon pair and the distance between them is also very small in comparison.
  • When all the engines on a craft are turned off, standard Newtonian mechanics apply to it causing it to orbit around the planet. This is only in this context. For all we know the gravity field of the planet could become ineffective as soon as you start moving your craft around.
  • The sun and the planets do not move, only the planets spin.

My hypotheses as to what the graph as whole represents, ranked in order of feasibility, is as follows:

  1. Gravity exists with engines on. The anomalous readings represent the vessel after rather significant changes in trajectory at points where velocity was low and high. At the lower velocity closer to the starting point at the moon the vessel made a change in course which required little acceleration because of the small velocity. Conversely, at the higher velocity close to the planet the vessel made a change in course which required a larger acceleration due to its higher velocity.  It can be argued that if the gravity of the two bodies was remotely significant, considering the pilot starts from the one of the poles of the moon, that he would veer way off course. But the ship is scripted so that when the pilot rotates the vessel all of the thrusters act to put it on the new trajectory, thus making larger accelerations. He clearly has a vertical booster and RCS. This would mean he would be accelerating downwards but the booster/RCS could easily compensate for the downward component of his acceleration. This is backed up by pre-alpha footage where you can see a ship’s VTOL thruster and main thruster acting in conjunction with one another. This hypothesis that gravity is acting upon the vessel is also backed up by the faction the gravitational pull is diminishing with displacement. In the video we can see the pilot does a roughly similar ‘jiggle’ before each of the points where the anomalies occur. It is larger at the second jiggle because the gravity is stronger and thus more acceleration is needed to correct the course.

 Conclusion

  • Pretty certain orbital mechanics still apply with engines on. Need to test the hypothesis and make it into a theory.
  • What is likely is a combination of more brake force and capped velocity in space vessels. A sweet spot between the two, so to speak, to make stopping easier but not exploitable
  • Unclear if fuel has mass. Need to test.
  1. This is sci-fi, overpowered engines are standard. It wouldn't be surprising if you could make a straight line to the moon. Though NQ may (hopefully) balance against that.
  2. It doesn't make sense to turn off gravity when a ship is moving, either from a programming perspective or an immersion perspective. While you'll save a few cycles, there are far bigger places that can get slashed first. Namely voxel interaction and manipulation.
  3. Planets don't spin. The sun is a skybox that revolves around the system.
  4. For your hypotheses: They'll probably have Air Brakes and Space Brakes. Space Brakes will only work in space. Air Brakes will only work in atmosphere.
  5. There is 100% going to be a speed cap. It's simply not possible to compute required physics over a certain speed.
  6. I believe NQ has said that fuel has mass and as it is used, you'll lighten up.

You are going seriously in-depth with so few resources! It's pretty awesome to watch.

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9 hours ago, AzureSkye said:

Planets don't spin. The sun is a skybox that revolves around the system.

Are NQ still considering spin or not? I'm not familiar with the term skybox: Do you mean planets are stationary and the spin the sun around them or some thing like that or an entire volume around the planets or some other weirdness?

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9 minutes ago, MookMcMook said:

Are NQ still considering spin or not? I'm not familiar with the term skybox: Do you mean planets are stationary and the spin the sun around them or some thing like that or an entire volume around the planets or some other weirdness?

https://en.wikipedia.org/wiki/Skybox_(video_games)

 

That's exactly what I mean. So far, nobody has really found the trick to make voxels rotate without crazy calculations. The theory that always gets suggested is "frames of reference", where you only move a bound section containing the voxels. NQ decided not to bite off more than they could chew. I imagine that they'll give it a shot at a later date.

 

(P.S: The + next to "Quote" allows you to multi-quote people in one post.)

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16 hours ago, KoshiHoshin said:

The point is to make the gravity field being zero in some points. Then in these points you will no longer "feel" the gravity field and if your velocity is null then you will stay on these points and so you are able to have an orbital "floating" station without needing it to have a velocity (as it's supposed to be built using static cores in the game) on the orbit of a planet. But by doing this you have to put your object very accurately otherwise it will oscillate indefinitely around the point (depending how far you placed the object from the equilibrium point supposing that the gravity field is the only force). So i guess they will likely introduce some friction (or anything that dissipates energy) to stabilize the position.

Interesting. But JC said that they would add planet spin. I'll look into it. But may I ask how do you know that anti gravity generators will be applied in this way? Source please?

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14 hours ago, AzureSkye said:
  1. This is sci-fi, overpowered engines are standard. It wouldn't be surprising if you could make a straight line to the moon. Though NQ may (hopefully) balance against that.

It's not the engines. It's the fuel. In real life I could make a craft with a VTOL thruster on the bottom to cancel out the acceleration due to gravity and make me go in a straight line. But such practice in real life  would be very high on fuel consumption as we have primitive fuel sources compared to that of the game. 

14 hours ago, AzureSkye said:

It doesn't make sense to turn off gravity when a ship is moving, either from a programming perspective or an immersion perspective. While you'll save a few cycles, there are far bigger places that can get slashed first. Namely voxel interaction and manipulation.

Perhaps you're right. I don't know much about scripting in games and it's limitations.

14 hours ago, AzureSkye said:

Planets don't spin. The sun is a skybox that revolves around the system.

You're right. Moving voxels won't go down well. I'll have to change my post on gravity.

14 hours ago, AzureSkye said:

For your hypotheses: They'll probably have Air Brakes and Space Brakes. Space Brakes will only work in space. Air Brakes will only work in atmosphere.

This is already confirmed in the atmospheric flight video tutorial

14 hours ago, AzureSkye said:

I believe NQ has said that fuel has mass and as it is used, you'll lighten up.

Can I get a source?

 

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Also I think there are some flaws in my reasoning I overlooked. I need to reevaluate my hypotheses again.

 

EDIT: updated both gravity and orbital mechanics posts. Gravity still exists dw

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4 hours ago, Veld said:

Interesting. But JC said that they would add planet spin. I'll look into it. But may I ask how do you know that anti gravity generators will be applied in this way? Source please?

Planet spin will not affect the gravity field. About the use of anti-gravity generators, in my opinion, they use it to solve the problem of space stations. Indeed as it is a building, it will require a static core unit as said in this video where JC also says "don't use that[speaking of the static core units] if you want to build anything that moves" so the velocity of constructions made with a static core unit will be zero from how i understand it. Then a problem arises. How can you make space stations (created from static core units) that requires velocity to stay on a given altitude in presence of a gravity field when by definition, you stated contructions made by these units will have no velocity. The solution is anti-gravity generators.

 

Also do not forget that even if NQ's function shows g as a scalar, it is a 3 dimensional vector. And in the video where you gathered the data, the ship acceleration is given as a scalar so the value only represents the acceleration in a given direction (the one of the ship i presume). Same goes for speed. So whenever the pilot is changing direction, both speed and acceleration are fluctuating. So i don't really know if the data you gathered can be used given the fact you don't really know what the pilot is doing.

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16 minutes ago, KoshiHoshin said:

Planet spin will not affect the gravity field. About the use of anti-gravity generators, in my opinion, they use it to solve the problem of space stations. Indeed as it is a building, it will require a static core unit as said in this video where JC also says "don't use that[speaking of the static core units] if you want to build anything that moves" so the velocity of constructions made with a static core unit will be zero from how i understand it. Then a problem arises. How can you make space stations (created from static core units) that requires velocity to stay on a given altitude in presence of a gravity field when by definition, you stated contructions made by these units will have no velocity. The solution is anti-gravity generators.

 

-snip-

Actually it seems like the antigravity units will be needed by the new flight mechanisms they mentioned in the recent news release .  Also, if static constructs by definition don’t have velocity, then gravity can’t move the construct.  This would mean that antigravity units would be more of a rp device on these structures than a necessity.

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43 minutes ago, Felonu said:

Actually it seems like the antigravity units will be needed by the new flight mechanisms they mentioned in the recent news release

Yeah i read that after posting. 

43 minutes ago, Felonu said:

 Also, if static constructs by definition don’t have velocity, then gravity can’t move the construct.  This would mean that antigravity units would be more of a rp device on these structures than a necessity.

True but I hope it doesn't work that way because it would mean that you could build anything anywhere floating around. So in this case, a space station would be a piece of cake to build which i think should be something hard enough to achieve because it is useful in many ways.

And well, i liked the idea of playing with gravity.

I'll try to test it tomorrow if i success to build a functionnal ship.

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16 minutes ago, KoshiHoshin said:

True but I hope it doesn't work that way because it would mean that you could build anything anywhere floating around. So in this case, a space station would be a piece of cake to build which i think should be something hard enough to achieve because it is useful in many ways.

There is nothing wrong with having things floating around, assuming you and your corp have the ability to pay for the fuel/energy that powers the anti-grav units, that is really the big logistics issue ;)

 

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Just now, CoreVamore said:

There is nothing wrong with having things floating around, assuming you and your corp have the ability to pay for the fuel/energy that powers the anti-grav units, that is really the big logistics issue ;)

 

I don't have anything against floating constructs but it should require something (energy, anti-gravity generators like you said it or something else). What i meant was that static core units should'nt be some magical stuff that let you built floating structures (and so defying the laws that apply to dynamic core units) without any other requirement.

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2 minutes ago, KoshiHoshin said:

I don't have anything against floating constructs but it should require something (energy, anti-gravity generators like you said it or something else). What i meant was that static core units should'nt be some magical stuff that let you built floating structures (and so defying the laws that apply to dynamic core units) without any other requirement.

Unfortunately thats the way it will work in game for the forseeable future as it is possible to dig the entire foundation out from under a mountain and have the mountain just float there. That may change some time in the far future, but for now thats the way it is :o

 

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19 hours ago, KoshiHoshin said:

Also do not forget that even if NQ's function shows g as a scalar, it is a 3 dimensional vector. And in the video where you gathered the data, the ship acceleration is given as a scalar so the value only represents the acceleration in a given direction (the one of the ship i presume). Same goes for speed. So whenever the pilot is changing direction, both speed and acceleration are fluctuating. So i don't really know if the data you gathered can be used given the fact you don't really know what the pilot is doing.

 A 3 dimensional vector, yes, but I would say the pilot maintains his acceleration in one plane within the realms of uncertainty in the context of how gravity is acting on him. I.e. even if he veered way off to the right or down he still shouldn't have got that negative acceleration at the second anomaly

 

Speaking of negative acceleration, acceleration is given as a magnitude and not a vector but you can tell it's negative as the given speed is decreasing at these times.

 

I took the values of accelerations only from times he was moving straight. The graph does not describe the journey as a whole. Should have made that clearer thinking about it. This means the only things that could have been altering his acceleration were the changing gravity vectors due to his changing position in the field, changing mass from fuel depletion and the impulse from the boosters to get his velocity vector to change.

 

The changing acceleration due to changing position in the field is there because he is full throttle all the time and will be unable to compensate fully with forward thrust to achieve the maximum acceleration he would get if he set off on the shortest path.

 

I cannot use this data to draw conclusions as I am unable to isolate the variable of gravity. I'm just using it to try and probe at what might be going on and discover which variable I might have to control in future tests.

 

As a sidenote one thing I actually missed was when he hits about 5k km/h his thrust goes down. Perhaps the velocity cap but couldn't spot a distinct pattern. I'll maybe analyse it later making a velocity time graph. Also I apologize if my scientific language is inaccurate. I'm not used to writing research notes like this. And thinking about it there are a lot of things I can stand to make clearer here as this is a pretty multilayered problem.

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23 hours ago, AzureSkye said:

https://en.wikipedia.org/wiki/Skybox_(video_games)

 

That's exactly what I mean. So far, nobody has really found the trick to make voxels rotate without crazy calculations. The theory that always gets suggested is "frames of reference", where you only move a bound section containing the voxels. NQ decided not to bite off more than they could chew. I imagine that they'll give it a shot at a later date.

 

(P.S: The + next to "Quote" allows you to multi-quote people in one post.)

Ah thanks yes I have come across skybox before. I see, rotating voxels and then as per the vid the difference between spinning planet and hovering above it problems.

 

It's easier to sometimes -snip- quote via highlighting the bit that interests me and add that. Sorry not adding anything to the discussion will lurk...

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14 hours ago, Veld said:

As a sidenote one thing I actually missed was when he hits about 5k km/h his thrust goes down. Perhaps the velocity cap but couldn't spot a distinct pattern.

I think it's because near planets, even in space, the atmosphere density is slighlty increasing. From how i see it in the video, it would impact your ship in 2 ways :

- 1) atsmosphere density creates a friction force probably proportionial to the velocity or square velocity so it will slow you. But you can't notice it because the atmospheric density meter precision is not enough to see it. I guess the force equation is something like : F=C(d).v or F=C(d).v² where F is the friction force, C a friction coefficient depending of the atmospheric density d (C being an increasing function of d) and v is your ship velocity. In space, i guess C(d) is very small but as you have a high velocity, the force is huge and slows you down very fast. That would explain why around 1.37, you have a high g value (i agree with you on the fact that it only shows the absolute value of g so always a positive value) but you are slowing down very fast. By doing so, if space has an atmosphere density then it creates a threshold for the velocity a ship can reach and then the maximum velocity you can reach is :

vmax=sqrt((m.g+F)/C) where vmax is the maximum velocity you may reach in a given direction, m is the mass of your ship, g is the intensity of the gravity field in that direction, F is the maximum thrust of your ship in that direction and C is the friction coefficient I mentionned before (I took the F= C.v² equation for the friction force). Of course this equation is for a given point in space as i expect g and C values depend on your position. This value can also be softcaped meaning there is a maximum value and so classical mechanic is no longer valid once you reached it.

- 2) atmosphere density impact the yeld of space engines meaning the higher the density the less space thrust you get from space engines. And it's the contrary for atmospheric engines. The higher the density the higher atmospheric thrust you get from atmospheric engines. From the video, around 2.45, you can see that space thrust is higly diminishing when the atmospheric density is greater than 0,01. And when it reaches a certain threshold (which i guess is 0,1 from the video) you have no longer space thrust. At 2.44, you can also see that atmospheric thrust is no longer 0 while the density meter still indicates a 0,00 density meaning the threshold for atmospheric engines is smaller than 0,01.

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On 07/04/2018 at 2:09 PM, KoshiHoshin said:

1) atsmosphere density creates a friction force probably proportionial to the velocity or square velocity so it will slow you. But you can't notice it because the atmospheric density meter precision is not enough to see it. I guess the force equation is something like : F=C(d).v or F=C(d).v² where F is the friction force, C a friction coefficient depending of the atmospheric density d (C being an increasing function of d) and v is your ship velocity.

I agree with this but one thing you have forgot to mention is the cross sectional area of the vessel

image.png.830872954fe6177c2b6093908873179a.png(IRL equation)

It doesn't make sense for NQ to make borg cubes just as aerodynamic as a fighter jet imo. I have begun an investigation into the atmosphere and so far evidence points to density not coming into play as a value on its own - as it does with regards to the planets (will talk about it more in depth in separate post). So I suspect C(d), rho and 1/2 are merged to a single coefficient specific to the atmosphere. I say atmosphere since I sincerely doubt NQ has the time to calculate friction coefficients specific to every single possible interaction between vessel surface and atmosphere. So they will probably just say D = C(d)Av^2

On 07/04/2018 at 2:09 PM, KoshiHoshin said:

In space, i guess C(d) is very small but as you have a high velocity, the force is huge and slows you down very fast. That would explain why around 1.37, you have a high g value (i agree with you on the fact that it only shows the absolute value of g so always a positive value) but you are slowing down very fast.

Adding this to separate hypothesis

On 07/04/2018 at 2:09 PM, KoshiHoshin said:

By doing so, if space has an atmosphere density then it creates a threshold for the velocity a ship can reach and then the maximum velocity you can reach is :

vmax=sqrt((m.g+F)/C) where vmax is the maximum velocity you may reach in a given direction, m is the mass of your ship, g is the intensity of the gravity field in that direction, F is the maximum thrust of your ship in that direction and C is the friction coefficient I mentionned before (I took the F= C.v² equation for the friction force). Of course this equation is for a given point in space as i expect g and C values depend on your position. This value can also be softcaped meaning there is a maximum value and so classical mechanic is no longer valid once you reached it.

Makes sense. If they use terminal velocity as an equilibrium in velocity due to atmospheric drag in the atmosphere it makes sense for them to use a similar model for space. This would  mean that the second anomalous reading was due to a combination of reaching a high point on the exponential curve of the graph of the 'space drag equation' and the instantaneously increasing atmospheric density. Mostly the atmosphere though.

On 07/04/2018 at 2:09 PM, KoshiHoshin said:

2) atmosphere density impact the yeld of space engines meaning the higher the density the less space thrust you get from space engines. And it's the contrary for atmospheric engines. The higher the density the higher atmospheric thrust you get from atmospheric engines. From the video, around 2.45, you can see that space thrust is higly diminishing when the atmospheric density is greater than 0,01. And when it reaches a certain threshold (which i guess is 0,1 from the video) you have no longer space thrust. At 2.44, you can also see that atmospheric thrust is no longer 0 while the density meter still indicates a 0,00 density meaning the threshold for atmospheric engines is smaller than 0,01.

It the atmospheric flight video you can actually see that your atm thrust is proportional to your peak engine thrust by a factor of the atm density itself. So if I have 100 kN thrust and i move up to say 0.84 atm I get 84kN thrust. The atmosphere seems to thin out faster with altitude in the actual planet which hints at there being some form of atmospheric layering system. As the decreasing of space thrust is not a linear relationship throughout and seems to cut off at a certain layer.

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Also new information with regards to thrusters: (source)

Quote

Piloting Mechanics revamp

We heard you. The previous piloting mechanics excessively relied on vertical boosters to leave a planet’s atmosphere and enter space. That wasn’t what we had in mind for these engines. Our goal is to have a set of engines that will cover different use cases so that specialized ships can be built depending on what type of mission is required. We have worked on a revamp of the engines, adding new ones such as the rocket boosters you saw in the DualX video, and redefining others. That includes Wing Elements, Anti-Gravity Generators, and lots of exciting new gameplay to experiment with! We will release a dedicated blog article with more detail about this very soon so that we can collect your feedback ahead of the launch.

This indicates you can still use vertical boosters to negate the effects of gravity but now we have a (implicitly) more powerful rocket booster to reach orbital delta-v.

However, to quote the first sentence, it is quite implicit that vertical boosters are not needed in space. But ultimately inconclusive.

 

Just realised something major I overlooked. The jet doesn't have any fuel in it. The fuel is cheated so that he can fly without it. That means the gradual changes in acceleration are in fact due to gravity

So gravity has to exist during flight. No doubt about it. Updating the posts. We can code lua scripts to make fuel efficient trajectories which will be very useful if you have shuttles constantly relaying resources from one point to another. But first we need to test the gravity equation and make a rework of classical orbital mechanics around it.

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Static constructs don't move. If you want to call it anti-gravity, go ahead. 

 

Dynamic constructs do move. However, they will also have restrictions on what can be placed on them. 

 

And since it seems we are going to have high impulse/high thrust engines, going straight to your destination, rather than computing a transfer orbit, will be the most common way of reaching a station. 

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5 hours ago, 0something0 said:

Wait, if dynamic constructs move in orbits while static constructs stay over one place via antigravity, then reaching space stations will become a pain...

It wont be an issue as your VTOL thrusters will be able to counter the gravitational pull. It would equivalent to landing on the planet itself. Think of the static space station as a really tall mountain with nothing but the peak. Also planets don't spin as of now so its not an issue.

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5 hours ago, AzureSkye said:

Static constructs don't move. If you want to call it anti-gravity, go ahead. 

NQ has something up their sleeve in mind for space stations. In response to the FB comment they said that the cores would be dynamic but would be a special case in building a space station. But as of now I think they're still static.

 

Edit: and shit i should probably start using multi quote

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