A Spring/Gas Based Impulse Space Propulsion System

[kerbiloid]

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7 hours ago, StrandedonEarth said:

15 hours ago, Terwin said:

3) do the contents of the box push/pull against something outside the box?

What we really need to do is find something new outside

Or change the meaning of the "outside" inverting it into a hyperdimensional box inside the ship. and stopping separating the ship from other universe. 

(Also it could provide a silent motorbike,)

***

The air intake efficiency depends on the velocity, so we can't totally treat it independently from the exhaust.

Edited December 3, 2020 by kerbiloid

[KerikBalm]

On 11/29/2020 at 4:34 PM, Spacescifi said:

It sounded good at first anyway.

I thought that if one part of the ship weighed heavier than the other that the impact might impart impulse.

Under this system, the center of mass of your ship dors not move, but you may displace part of your ship - like the nose going forward as the plate goes back. But then the nose goes back as you retract the plate.

All cycling this does is to shake the ship, and never move it anywhere. Center of mass never moves, the ship just shakes around it.

[Spacescifi]

2 hours ago, KerikBalm said:

Under this system, the center of mass of your ship dors not move, but you may displace part of your ship - like the nose going forward as the plate goes back. But then the nose goes back as you retract the plate.

All cycling this does is to shake the ship, and never move it anywhere. Center of mass never moves, the ship just shakes around it.

 

Hmmm.

 

Take a cylinder of steel with an astronaut wearing magnet boots.

 

He has a rubber ball with a lead core, so it's a heavy ball.

He walks to the middle of the cylinder, lifts off the floor, and throws the ball as hard as he can at the front wall.

The front wall has sticky adhesive. The ball does NOT bounce back. The astronaut floats toward the ceiling and flips to reaatach his boots. Then runs forward a bit so he does not fall to tge rear wall.

 

Does THAT impart forward impulse?

Hardly practical. Just curious 

 

 

[KSK]

Nope.

The astronaut starts at rest relative to the cylinder.  Net momentum is zero.

He throws the ball giving it momentum - and himself an equal and opposite momentum. Net momentum is still zero.

The ball sticks to the wall transferring its momentum to the cylinder.

The astronaut sticks himself to the cylinder transferring his equal and opposite momentum to it in the process.  Net momentum is still zero.

It’s that reattachment of the astronaut to the cylinder that spoils things. When the astronaut comes to rest (relative to the cylinder), his momentum has to go somewhere.

If the cylinder was open at one end and the astronaut flies out of that open end, then yeah it would work. Once.

 

Edited December 3, 2020 by KSK

[RCgothic]

Nope.

Consider the before and after. Is anything moving with respect to anything else? If not, you have not given anything a NET impulse.

It doesn't matter what part of the spacecraft the astronaut touches - whether the back wall, the side wall, or hanging from a rope from the front. The moment she goes back to the same speed as the spacecraft nothing has really changed except the internal distribution of mass.

The only way to get a NET impulse is to eject something from the system.

Edited December 3, 2020 by RCgothic

[Spacescifi]

34 minutes ago, KSK said:

Nope.

The astronaut starts at rest relative to the cylinder.  Net momentum is zero.

He throws the ball giving it momentum - and himself an equal and opposite momentum. Net momentum is still zero.

The ball sticks to the wall transferring its momentum to the cylinder.

The astronaut sticks himself to the cylinder transferring his equal and opposite momentum to it in the process.  Net momentum is still zero.

It’s that reattachment of the astronaut to the cylinder that spoils things. When the astronaut comes to rest (relative to the cylinder), his momentum has to go somewhere.

If the cylinder was open at one end and the astronaut flies out of that open end, then yeah it would work. Once.

 

 

It was worth a try 

Hey!

What if the cylinder had air inside and a hovering flying drone shot bullets at the forward wall but never landed?

Granted...I know, recoil.

But what if the entire ships was shaped like a torus (donut)?

And two drones, in on each side, fired simultaneously at the front wall?

The recoil shoots them back, but if the ship is BIG and spacious enough that the drones can fly and curve around as much as they want with without hitting the walls.

Only up to a point, since eventually the rear wall will catch up to them...I think if they keep shooting at the forward walls.

 

I am guessing. It's interesting.

Edited December 3, 2020 by Spacescifi

[RCgothic]

The drones push on the air which pushes on the spacecraft. No net impulse without ejecting something from the system. Conservation of linear momentum.

If they fly around the torus then they would spin the torus in place in the opposite direction whilst they are flying. When they stop the torus will stop.  Conservation of angular momentum.

This second is actually a useful effect, because you can stop the spin pointing in a different direction by changing where you stop. It's used with gimbals for attitude control and fine pointing  on existing spacecraft.

[K^2]

On 11/30/2020 at 3:47 AM, magnemoe said:

Who would work, you blow on the sail, the wind is reflected and this pushed the boat forward.
Mythbuster tested this with an huge fan and a sail, they did not expect the boat to move

They just stole my idea.  This is from back when I taught physics labs. Yes,  phone cameras sucked back then.

 

[YNM]

5 hours ago, Spacescifi said:

Take a cylinder of steel with an astronaut wearing magnet boots.

 

He has a rubber ball with a lead core, so it's a heavy ball.

He walks to the middle of the cylinder, lifts off the floor, and throws the ball as hard as he can at the front wall.

The front wall has sticky adhesive. The ball does NOT bounce back. The astronaut floats toward the ceiling and flips to reaatach his boots. Then runs forward a bit so he does not fall to tge rear wall.

 

Does THAT impart forward impulse?

You could have simplified this by having a free-floating astronaut just do squats in space and expect overall acceleration.

Moving mass around inside any vessel would only move the CoM wrt the vessel but the CoM itself doesn't accelerate wrt the "static" inertial observer.

4 hours ago, Spacescifi said:

What if the cylinder had air inside and a hovering flying drone shot bullets at the forward wall but never landed?

Granted...I know, recoil.

But what if the entire ships was shaped like a torus (donut)?

And two drones, in on each side, fired simultaneously at the front wall?

The recoil shoots them back, but if the ship is BIG and spacious enough that the drones can fly and curve around as much as they want with without hitting the walls.

Only up to a point, since eventually the rear wall will catch up to them...I think if they keep shooting at the forward walls.

We have coolant liquid (ammonia) flowing in a closed loop around the ISS between the pressurized modules and the radiators, and to the best of my knowledge we haven't seen any thrust coming off of them.

Although you could be exchanging rotation with the station much like the way CMGs work. But CMGs only rotate your ship around and not have it shoot out (or fall off) the orbit.

[kerbiloid]

Attach a pack of astronauts to the ship nose with tethers and make them jump forwards to pull the ship.

[magnemoe]

3 hours ago, kerbiloid said:

Attach a pack of astronauts to the ship nose with tethers and make them jump forwards to pull the ship.

Going out and pushing works in KSP   Granted they use the suit thrusters who would also work in real life. However the KSP suits has something more like jet packs than rcs and they refill on entering the capsule again.  

 

[KerikBalm]

10 hours ago, Spacescifi said:

It was worth a try 

No, it wasn't.

10 hours ago, Spacescifi said:

What if the cylinder had air inside and a hovering flying drone shot bullets at the forward wall but never landed?

No. Haven't you realized yet that you're not going to get around this, that the forces will always cancel out.  Putting in more steps /intermediates doesn't change anything.

Now you've just added air as an intermediate, but it changes nothing. Equal and opposite forces are exerted. 

A=B, B=C, C=D, A=B=C=D, thus A=D. Its really very very very simple math, the transitive property. Sticking steps B and C in between A and D change nothing. The force is equal and opposite... do you have any reason to think any given step does not have an equal an opposite reaction?

[KerikBalm]

50 minutes ago, KerikBalm said:

do you have any reason to think any given step does not have an equal an opposite reaction?

and if you did, just do that step, without all these other intermediates!

[kerbiloid]

1 hour ago, magnemoe said:

Going out and pushing works in KSP  

Not jetpacks. Just jumps.
Why throw that resinball inside the bay when they can just jump themselves.

[Entropian]

I probably ought to put this here:

[Arugela]

 

What is the point people keep making with the picture of people blowing into a sail? This is the problem with not using your own words. It's probably better to state the argument so people know what your point is. It works in practice. It's literally how a boat works. It's not a matter of no energy on a ship can do this because it has nothing to do with a closed cycle... Which isn't true to start as there could be ways to make some part of a closed cycle act while not reacting in the other other direction because of the type of interaction and it isn't even a closed cycle. So, is this an argument on efficiency?

For the sail to outdo the motor all you need is enough concentration, or whatever makes it move, produce more power than the blades. If the blades are not efficient you can have any type of conversion in the other direction. The next response will likely be that is it's not enough to work because were so efficient. This is not true on it's face.

The next part is for overall efficiency. Is there a reason to blow forward over backwards. Better materials. Generating electricity to extend battery life mechanically.(these are just examples.) There could be a practical reason to go with a more wasteful solution in one area. The more complex things you consider(real life ones) the more you will run into reasons to potentially do this. (including simple blind choice. Which there is no true blind choice. There is still a reason we pick things. This is ultimately experimentation and a chance to learn new things. This requires a limitless amount of use to test and can never be done enough.)

The spinning in the water can actually be useful. Especially with real boats or similar. If you add a rudder, it's can go straight. This is for reasons when you need to go straight when not in an optimal position. You could even wiggle the rudder back and forth to get close to even. I wonder if you can get extra forward motion like those little wiggle carts that propel you forwards as you use them. It's probably used with real boats.

And is the fan backwards more efficient on it's own or because it's pressing against air from the other fan blowing forwards. This is where it gets complicated, because assuming overall what you are seeing explains anything is not correct logically. You don't now how many minor things are in place. It's very hard to test for complexity. You could eventually run into things makes a combination of other factors making forwards more efficient. And that is simply going for one parameter. Which doesn't work that smoothly in real life. Even the fan moving better backwards on it's own doesn't mean anything. If you are oversimplifying the situation you could be missing something that could be utilized. (And you must always assume you are over simplifying.)

On top of all of this how is what you are seeing produced. You can assume all you want and call it established theory. But that theory is the literal thing you are looking at(Another test) and hence not a limiting factor. You could have endless things in play we can't see or test sufficiently. This is besides individual understanding and more depth into how we interpret information compared to a limited data set in the brain on a person to person basis. We don't know how much we don't know. All theory is based on simplified information. You have to assume all of that is broken by increased complexity which can always change any aspect. That is basic logic. Or proper science. Accuracy. And you can't expect examples to explain this. You can never give enough examples as it's from the same limited data set in any individuals brain. And even collectively via communications. The unknown is the unknown and must be treated as such.

You cannot account for if you have accounted for everything. It's a logical and mechanical impossibility for people. And most of the arguments I see are based on the premise. Including thinking any so called testing accounts for the maximum potential for anything. It's never true.

And no matter how much it works it's still not an argument. You don't know that the current practice is sufficient to account for unknowns. And you never know how many unknowns are not accounted for.  Any such argument is fallacious on it's face. No guestimate is ever logically acceptable. Unless accounting for a very limited set and accepted as a limited data set accepting the lack of known unknowns. Which is the true way to deal with such a thing.

Simplest example. If the engine doesn't thrust forward. It's by definition another form of machinery. If you like efficiency is it more efficient or more convenient in any way compared to existing.

The irony is you are all potentially arguing from a standpoint that physics may go infinitely downward to produce matter. If you follow that logic....

Edited January 22, 2021 by Arugela

[Arugela]

On 12/4/2020 at 8:52 AM, Entropian said:

I probably ought to put this here:

And I'll point this out. Flip a card over and draw on it. Or use the back as card. He didn't say he physically added a card. Logically you can represent cards all day long. That is already what a card is. If you flipped the cards upside down or anything else.

Especially easy if the cards already have flaws in them to use as identifiers. Or the cards are already specially marked for such a things.

What do you know, the corner on that card is bent. I bent it during shuffling. If it's backwards it's now  an ace of bent. BTW, this is usable for many things potentially. You just have to expand your understanding sufficiently.

There is nothing impossible about this.

And the bottom caption is correct.

(And if you want the physical argument you simply tear one in half or such during shuffling and arranging. Then you have one extra card. Or two extra of one card as the cards are literally mirrors of themselves. This is the simplest argument possible. And the only one not based on a complete fallacy. It's ironic this meme is presented on a deck of cards that literally is the easiest such thing to make such an argument. The cards are designed for it. ASK ANY MAGICIAN!!!)

Change the caption from perpetual motion enthusiast to magician and all such arguments will suddenly make sense.

He said he cut the cards. The trick is how he got 1 extra and not 52 more.

There is no parameter saying the cards must be the same dimension. This is outside of using it as an illusion behind other cards where it could appear to be one extra same sized card. And the fact it's in half means it's even literally an extra card making such an argument completely true. Not to mention any such card trick could count as fulfilling the statement. Including shuffling an extra card into the deck!!!!!! 52+1=53.........

Anything in magic or other fields are always equivalent to functional machinery somewhere. It's all applicable. To something. If you think otherwise you are just looking at it wrong.

Edited January 22, 2021 by Arugela

[Arugela]

On 12/2/2020 at 10:54 PM, StrandedonEarth said:

What we really need to do is find something new outside the box to push/pull against. Antigrav, quantum foam, aether, fabric of space-time, zero-point energy, something. That is what we need for a propellantless space drive that's more energy-efficient than a photon drive.

Would it be possible to grow a small enough self sufficient solar sail run by a gerbal on a wheel constantly fed recycled water and food from a closed system? If needed with a small breeding program. I guess that is technically inside the box.

On 12/4/2020 at 4:52 AM, KerikBalm said:

No, it wasn't.

No. Haven't you realized yet that you're not going to get around this, that the forces will always cancel out.  Putting in more steps /intermediates doesn't change anything.

Now you've just added air as an intermediate, but it changes nothing. Equal and opposite forces are exerted. 

A=B, B=C, C=D, A=B=C=D, thus A=D. Its really very very very simple math, the transitive property. Sticking steps B and C in between A and D change nothing. The force is equal and opposite... do you have any reason to think any given step does not have an equal an opposite reaction?

Technically it could work. You just have to get the bullet to apply force and never hit compressing air in an increasingly efficient/inefficient manner until you reach your destination. The rest has to be figured out afterwords. If the effect only last so long it doesn't matter. You could even bail out before the return force. Or load up passengers for a return trip.

Edited January 22, 2021 by Arugela

[KerikBalm]

3 hours ago, Arugela said:

*incoherent nonsense as far as I am concerned*

What?

Just... what?

I'm sorry, but I cannot extract any coherent idea or concept from the text you have typed. can you attempt to reformulate it with an emphasis on making it understandable to someone who doesn't already know what you are trying to describe?

[YNM]

6 hours ago, Arugela said:

For the sail to outdo the motor

I'd like one to try it in vacuum. It's supposed to be for space, right ?

5 hours ago, Arugela said:

If you flipped the cards upside down or anything else.

I see that you're playing a different table-top game.

4 hours ago, Arugela said:

Would it be possible to grow a small enough self sufficient solar sail run by a gerbal on a wheel constantly fed recycled water and food from a closed system?

Solar sails work by having the Sun in vicinity. It wouldn't work in deep space (think interstellar or even intergalactic space). And the Sun (and other stars) will die (stop shining light) at some point.

Also, at some point the animal will die. I call animal cruelty for being worked long hours.

4 hours ago, Arugela said:

get the bullet to apply force and never hit compressing air in an increasingly efficient/inefficient manner

We've had wars for long enough in this world where bullets are being fired, and I haven't seen the Earth change it's rotation from this effect at all. Or the weather (wind directions) for that matter.

[kerbiloid]

This, but golden.

Spoiler