It's just a draft, arrows length doesn't mean how strong the thrust is, and it's not 45°, since the OP didn't turn past the point that makes the ship stops in a straight line. I was trying to show the OP that the forward thruster didn't make the ship go downwards, the vertical thruster did. The forwards thruster didn't output any thrust in OP's case.
Zero throttle but still thrusting?
- Thread starter bladebss
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It's just a draft, arrows length doesn't mean how strong the thrust is, and it's not 45°, since the OP didn't turn past the point that makes the ship stops in a straight line. I was trying to show the OP that the forward thruster didn't make the ship go downwards, the vertical thruster did. The forwards thruster didn't output any thrust in OP's case.
Thanks, I'll take a look at the vids when I'm on wifi!
Re the reaction mass, yes, that's the problem right. To use the tiny amounts of fuel needed / imagined in the game, exhaust velocity has to be immense. As you say, about half the speed of light!
For frame of reference; Saturn 5 exhaust velocity was about 2-3 km/s. Exhaust velocity needed: a cool approx 150000 km/s!
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Bob Lighthouse
Banned
I have throttle and thrust bound separately, is that the issue here?
Seems people are conflating the two.
Seems people are conflating the two.
Ok, so just to clarify, there’s different things at different points in the video. When you set the desired speed to zero, your ship starts thrusting backwards. When you steer your ship down, thrust is being applied in various directions, and the net thrust is going to be different on different parts of the ship, and this will vary at different parts of the turn.
Just to shed some light on why you wouldn’t move up, let’s consider your starting situation. You’re travelling in a straight line with speed A, so treating it in (x,y,z) your velocity is (A, 0, 0). Ignoring FA for now, if you rotate your ship to face say 45 degrees down, and use reverse thrusters to give a thrust F, what you get in forces in (x, y, z) is (-0.5F, 0.5F, 0). That sounds to be kind of what you were expecting to happen. The thing with this however, is that as you’re reducing the x component of your velocity, you’re also increasing the y component. This would mean your speed isn’t decreasing, it’s staying the same, and all that’s changing is the direction of movement.
However, with FA on, you’ve set your desired speed to zero and FA is trying to do that for you. If FA wasn’t also trying to match your orientation with your directional travel, then what it would be doing is firing a combination of thrusters so that the net thrust was in the - x direction and there was zero thrust in the y direction. In other words, there wouldn’t be any movement in the original up direction
Of course FA is also trying to match your direction of travel with your orientation. As a result it’s a combination of slowing down your speed, whilst also changing your direction of travel.
Anyway, what this all boils down to is there’s a simple way of doing what you wanted to do (in terms of avoiding the structure at least). Rather than changing orientation, just directly apply thrust in the direction you want to go - i.e. use your up thrusters. I hope that makes sense and clears things up a bit!
Yeah, that central issue’s just one that we’ve got to put aside for the sake of the type of game IMHO. I mean it’d be interesting in other circumstances but I’m glad it’s not something in Elite.
For the other forces, can we just double check on those? To cover a few things:
Gravity does take effect. If you take off from a planet’s surface, then turn FA off, you’ll drop.
In terms of orbits, etc. your speed is measured compared to the local reference frame. However those reference frames are moving. So if that reference frame is moving in orbit, so are you.
Coriolis forces are there (in stations at least). Rotational Correction masks the Coriolis Force.
What were the other forces you were thinking of?
Actually, I believe those were proven to not be true Newtonian Orbits.
If they were, you could fire your thrusters retrograde or prograde and affect the height of your orbit as you deemed fit, more specifically affecting the height of your periapsis and apoapsis, while still staying in orbit.
You cannot.
You absolutely can, within the limits of both the maximum speed of your ship and the maximum height at which horizons planets extend their gravity's sphere of influence.
If forward thrust is what's used to achieve the change of direction of travel then they're asking for what I said, under the circumstance of desired speed being set to zero.
It's not just a small detail is it though. Matching the direction of travel with your orientation is a key part of FA. Switching that part off in the circumstance of desired speed being zero is a fairly big change, and again it effects everyone who ever flies FA on.
SO.....
Firstly, this is a complex subject, so where my points have not been sufficiently specific, my apologies. In addition, I don't want any changes to the physics. The OP was looking to understand why his ship behaves the way it does; it led us here.
WRT to physics, I should have said that the game models some aspects of this in some situations. I was primarily thinking of normal space, not inside the orbital cruise sphere.
In that context, it does not model gravity, orbital velocity etc. By this I mean you can come to a full stop, go FA off and just remain stationary. Thrusting contra to the bodies rotation will also not decrease orbital height for instance.
WRT to reaction mass I understand the point you're making, but physics is a system. We can't insert a "0" for force or mass into the equation and still say "hey we're following newtonian physics". What we can say is that FDev made a computer model that, here and there, reminds us of some aspects of physics.
The acid test is this; we are all interested in space, spaceships etc, and we all watch the news, documentaries, what have you. We know from all these things that space craft cannot maneuver in the way they do in ED.
Right there, that is the klaxon-call that ED as a game does not behave in a physics-real way.....nor should it.
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ED is intrinsically incapable of basic spaceflight, period.
It's not that kind of game, unfortunately.
Play Frontier Elite if you want to actually control the ship yourself. FFED3D or Pioneer are the best options..
What ED offers is canned FX, with extremely (comically) limited control and performance. And 'XP points'. For jumping thru flaming hoops. It's a linear, by-the-books 'Skinner box' game - the very antithesis of everything that made its predecessors so compelling..
It's not that kind of game, unfortunately.
Play Frontier Elite if you want to actually control the ship yourself. FFED3D or Pioneer are the best options..
What ED offers is canned FX, with extremely (comically) limited control and performance. And 'XP points'. For jumping thru flaming hoops. It's a linear, by-the-books 'Skinner box' game - the very antithesis of everything that made its predecessors so compelling..
whats with all that off-topic discussion about newtownian flight, when the topic is just about the OP want Flight assist to only work on the
yaw/roll/bank axis when he has set his throttle to zero.
he expects the Flight assist only to counter his inputs when he is not giving them (stop rotation when no rotation signal is given, stop thrust when no thrust signal is given)
in other words - he wants even more then what M+K users get in FA-Off with relative mouse mode.
yaw/roll/bank axis when he has set his throttle to zero.
he expects the Flight assist only to counter his inputs when he is not giving them (stop rotation when no rotation signal is given, stop thrust when no thrust signal is given)
in other words - he wants even more then what M+K users get in FA-Off with relative mouse mode.
It doesn't ignore mass.
Actually, FA On doesn't ignore mass or momentum either.
It ignores none of these, except probably reaction mass, which is irrelevant (it hardly matters where the force comes from for the purposes of approximating Newtonian motion of the object itself, just that it's there).
Almost everything you think it ignores is actually an active counter force being applied.
There is considerable computer assist/limitations with FA "Off". It's a misnomer, and should be called FA high and FA low.
Regardless, other forces absolutely do apply to the ship, mostly as they should.
You can actually orbit planets in free fall, if you can find one where the orbital velocity is within the constrains on speed that are always applied by the flight computer. This has been demonstrated countless times.
Your ship will react as it should to the impacts of other objects that have modeled momentum and to the forces applied by it's own thrusters, even if the reaction mass itself is abstracted.
Yes, and this is exactly what happens:
[video=youtube;LGtRDFbUvgI]https://www.youtube.com/watch?v=LGtRDFbUvgI[/video]
The overwhelming majority of your criticisms are due to you not paying attention to how the game actually works.
It's not a problem unless the reaction mass would need to be equal or higher than the speed of light to account for the momentum applied. It doesn't.
Trying to compare a chemical rocket to whatever the hell our ships are doing with the exhaust from their fusion reactors isn't useful. It might violate conservation of energy in some cases, by requiring more power than the thruster modules are stated as using to accelerate the reaction mass, but that bit of handwavium could be fixed by sticking another digit on the power output/consumption figures, if they wanted to.
Regardless, it none of the really detracts from the fact that, within the bounds of some arbitrary speed caps, our ship do follow a Newtonian physics model.
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My friend you and I just had this conversation in an earlier thread.
I set you a challenge to complete in Kerbal to prove you are right.
And you're still wrong.
And still irrelevant.
I've played Kerbal and that it's less abstract and doesn't feature technologies that don't exist doesn't change the fact that the basic physics model of Elite: Dangerous is quite Newtonian.
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Last time we had this exchange I was quite explicit that I had no desire to spoil your day, and I offered a gentleman's challenge so you could prove where ED is true to life and where it isnt.
However, your tone suggests you would quite like to spoil my evening, so with that I will bid you a pleasant evening.
Dude, your bitterness about the flight model belies your nick; it has no bounds.
I wasn't aware of any 'tone'.
Last time we had this exchange you did precisely what you've done in this thread, which is grossly misrepresent what Newtonian physics entail while expressing ignorance of how ED works.
Newtonian physics is what you get when objects obey Newton's laws of motion. By and large, our ships in Elite: Dangerous do this. They don't always behave as you seem to expect, but that's largely due to you misinterpreting what constrains are applied by the flight control system and when.
As long as you are not exceeding any velocity limits relative to one's current frame of reference, ships behave as they should. This has already been demonstrated and is something you could easily test yourself.
You tell me to play Kerbal. I suggest you play ED. If you pay attention, the difference is less of which adheres to Newton's laws better, and more of detail vs. abstraction of how forces are applied.
Sideline viewer here, just curious what this Kerbal challenge was, if you don't mind sharing.