What Are the Implications of Reaction Torque Propulsion?

[Ray Payette]

I never claimed that it doesn't require energy. Where did that notion come from? The model uses a 9 volt battery and it creates no energy whatsoever.

The model is a hovercraft that floats on a cushion of air. That is not what propels it.

 

[russ_watters]

I never claimed that it doesn't require energy. Where did that notion come from? The model uses a 9 volt battery and it creates no energy whatsoever.

You misunderstand: anything that moves has to obey conservation laws: either action-reaction (the hovercraft moves in one direction, another mass, like air, moves in the other) or it must exert a force on a stationary object like the ground. Your device, the way you describe it, exerts no force on the ground or air, so it doesn't obey conservation laws.

The propellers on your hovercraft should make it shake back and forth - when the propellers move forward, the hovercraft should move backwards and when the propellers move backwards, the hovercraft should move forward. You can see this vibration occurring in your video. The vibration is quite clearly the primary effect of your device. The secondary effect is what is making it move forward. Remember, since its a hovercraft, it takes very little energy to move it forward, but clearly there is a lot of energy in the vibration. If only a tiny fraction of the energy goes into unbalancing the hovercraft, its going to move. And that's what's happening.

The model is a hovercraft that floats on a cushion of air. That is not what propels it.

It is clear from the video that it tilts forward due to the flexible motor mounts. That very well may lift the back enough for the lifter fan to propel it forward.

Here is a math problem that hopefully you can do: assuming no friction, how much force (and then work and energy) does it take to move a 2kg hovercraft forward 2 feet in 5 seconds?

Compare that to the power output of those motors and see if you get a significant fraction of the motor power output.

 

[Entropy]

The model is a hovercraft that floats on a cushion of air. That is not what propels it.

You do know that hovercrafts can still drift in a specific direction due to an imbalance in the pressure of the air under it, don't you? In fact this is pretty much inevidable seeing how you can get exactly even pressure. How do you know this isn't the cause of the movement?

 

[russ_watters]

Lemme clean that up for you, Entropy...

You do know that hovercrafts can still drift in a specific direction due to an imbalance in the pressure of the air under it, don't you? In fact this is pretty much inevitable seeing as how you can't get exactly even pressure. How do you know this isn't the cause of the movement?

Indeed, it is difficult enough to get a hovercraft stable when it is flat - when it its shaking, rolling, and pitching, its just not possible.

 

[russ_watters]

Let me characterize this in another way. There are two ways to describe what is going on here:

First, take the hovercraft as a whole and find the action and reaction. If the hovercraft moves forward on a frictionless surface, something (air) must go in the other. This is the easy way - its just high-school Newtonian physics. Action:reaction.

Second, take the component parts of the hovercraft and model exactly what they are doing. This is the hard way as it requires college level engineering to describe (which isn't to say with some reading-up you can't figure it out without taking the courses: search for some info on Engineering Statics and Engineering Dynamics courses).

The problem is you think you know what the hard way will show and as a result, you're ignoring the obviousness of what the easy way says.

 

[Ray Payette]

The actions are rotating loads. A motor that turns a load produces a rotating force, in other words a couple. This has to be compensated by an equal and opposite reaction, in this case a couple that turns the hovercraft in the opposite direction. That is the essence of the device. A motor turns a load; that makes the hovercraft turn in the opposite direction.

If there were a strong imbalance caused by the vibration that would push the hovercraft forward, then it wouldn’t pass the traction test. But it did.

The facts are that the hovercraft moves forward and it passed the traction test. Another fact is that there are many vibrations, but how can you explain that these vibrations propel the hovercraft forward? Old propeller planes really shake around also, but that isn’t what propels them.

 

[Alkatran]

The actions are rotating loads. A motor that turns a load produces a rotating force, in other words a couple. This has to be compensated by an equal and opposite reaction, in this case a couple that turns the hovercraft in the opposite direction.

Ever take a physics class? The reaction happens at the same time as the action, not later.

 

[Ray Payette]

Exactly, at the same time the motor turns the load the hovercraft turns in the opposite direction.

 

[Alkatran]

Exactly, at the same time the motor turns the load the hovercraft turns in the opposite direction.

It takes energy to start this turning. It takes energy to stop it. It takes energy to keep it going because of friction. Cars are faster and more efficient.

 

[Ray Payette]

Perhaps cars are faster and more efficient here on earth, but they don't work in space. This form of propulsion is an alternative to rockets.

 

[Alkatran]

It won't work in space, momentum is conserved. If momentum is not conserved then Newton's third law is false, everything we know about collisions is false, etc etc etc...

Basically, physics changes completely.

So... until you do it in space I don't believe it.

 

[Ray Payette]

That's a new one, the physics in space are different. Since you are well versed in that subject, could tou please give me a reference that would state that.

 

[enigma]

That's a new one, the physics in space are different. Since you are well versed in that subject, could tou please give me a reference that would state that.

No, physics is space are the same.

The environment in space is different.

Your craft is getting propelled somehow... most likely aerodynamic forces from the propellers or non-uniform pressure distributions along the skirt. You don't have air to move it in space, therefore it won't work in space. You can't get energy from nothing.

Why don't you try to suspend the thing from a string and run it then.

If you truly have something, the device will oscillate about some non-plumb equilibrium position.

 

[Ray Payette]

There are no propellers, only wooden rods that don't displace much air; they cannot possibly provide the hovercraft's propulsion.

The energy from the battery is converted to kinetic energy. Energy is used up from the battery.

I suspended the device on a cushion of air that provides more degrees of freedom than a pendulum. Since there are rotational forces involved (reaction couple) and the vehicle needs to stay on the same plane, 3 wires would be required to stabilize it. This in turn would pose tortional questions. The hovercraft is a better experiment.

 

[mapper]

Next time I am in space ill do your experiment. Sounds like fun.

btw what video codecs do we need to view this video? I've dl like 10 different ones and nothing works still.

 

[Ray Payette]

It should work in space because it doen't interact with the environment at all; it needs no air to move or surgace to push in order to work.

Try the latest Microsoft Media Player. There are 23 megs .mpg files so you might need to delete your temporary internet files as the TIP suggests.

 

[enigma]

It should work in space because it doen't interact with the environment at all; it needs no air to move or surgace to push in order to work.

This is an unsubstantiated assertion, and quite frankly, incorrect.

You cannot get kinetic energy without pushing against something. Sorry... that's just the rules of this universe.

Without measuring it, you have no justification to just write off the aerodynamic effects of the rotating beams. Without measuring it, you have no justification to just write off the potential for a pressure difference across the edge of the skirt caused by the vibrations.

Satellites use reaction torque NOW! All the torque wheels do is adjust orientation. No free energy. No fuel-less motion. What's more, after a while, they need to be de-spun by firing the attitude control rockets while they torque the wheels in the opposite direction.

If you think you've found something new, then you MUST quantify it or else you have no way to justify spending millions of dollars to design, build, launch, and test a device in space. If you can't quantify it yourself, then find someone to do it for you. You can either pay someone or actually listen to what people here are telling you... either way you'll get the same response. Torques cannot increase linear momentum without pushing against something.

Do the string experiment. I'm willing to wager whatever you can afford that you'll find you have no equilibrium offset.

 

[Ray Payette]

You contradict yourself. First of all you state that satellites use reaction torque now. Yes they do, they use reaction wheels to maintain their attitude. They don’t have to push against anything to do this. So you implicitly agree that a rotary means of propulsion is not only feasible, it is in fact used in space. In fact my invention refers to US patent 5,723,923 concerning a reaction wheel. In one version of my patent I use that same reaction wheel to produce the rotations on a satellite. The sum of these rotations result in a linear momentum, but they originate as rotational torques.

BTW it is an erroneous notion that propulsion has to push against something. When in space rockets simply throw away their burnt fuel in space against nothing. All you need is an action to get a reaction. Get your notions correctly!

If you examine my website well enough you will see that it also solves the momentum build-up problem by a momentum unloading procedure.

I was a chartered accountant for decades so I know that I could discuss numbers for years without achieving a conclusion. That is a quagmire I do not wish to go into.

 

[russ_watters]

You contradict yourself. First of all you state that satellites use reaction torque now. Yes they do, they use reaction wheels to maintain their attitude. They don’t have to push against anything to do this. So you implicitly agree that a rotary means of propulsion is not only feasible, it is in fact used in space. In fact my invention refers to US patent 5,723,923 concerning a reaction wheel. In one version of my patent I use that same reaction wheel to produce the rotations on a satellite. The sum of these rotations result in a linear momentum, but they originate as rotational torques.

Again, rotational motion is not the same as translational: the contradiction is in your own understanding of the subject, not in enigma's. You do not use the same reaction wheel as the satellite, you use an unbalanced "wheel." If you think that's trivial, try using two balaced wheels in place of the rotating sticks. You'll end up with a quite stable (vibration free) and motionless object - like a dual-rotor helicoptor sitting on the ground. The similarity between your device and a satellite w/reaction control is that neither can produce translational motion, only rotational.

If you do the math, you will find that what you have constructed, if working correctly, makes the hovercraft oscillate like an orbital sander due to the unbalanced rotation.

The energy from the battery is converted to kinetic energy. Energy is used up from the battery.

That's true, but you're still missing where that energy is going: an electric motor obeys conservation law. The motor produces a torque on the shaft and the shaft produces an equal an opposite torque on the motor. This cannot be mechanically converted into translational motion without coming into contact with the environment.

Conservation law does not say that consuming electrical energy can result in unbalanced mechanical energy. Both the mechanical and electrical systems obey conservation law separately and collectively.

 

[russ_watters]

The actions are rotating loads. A motor that turns a load produces a rotating force, in other words a couple. This has to be compensated by an equal and opposite reaction, in this case a couple that turns the hovercraft in the opposite direction. That is the essence of the device. A motor turns a load; that makes the hovercraft turn in the opposite direction.

Right - and the part that you're missing, the part that requires a little math or engineering work to show, is that the two couples cancel each other out, resulting in no forward motion.

If there were a strong imbalance caused by the vibration that would push the hovercraft forward, then it wouldn’t pass the traction test. But it did.

That has nothing to do with traction, that's the fan pushing the hovercraft forward.

Another fact is that there are many vibrations, but how can you explain that these vibrations propel the hovercraft forward? Old propeller planes really shake around also, but that isn’t what propels them.

I did explain it, you just won't accept it. Speaking of old planes, did you know that if the pilot of a WWII fighter didn't counter the torque of the motor, the plane would flip over? Action-reaction is obeyed there as well. Also, the vibration of your device far exceeds its propulsion, unlike with an old plane. In fact, I'd wager that if you ever chose to do the calculation I laid out above, you'd find upwards of 90% of the mechanical energy produced by those motors is going into making it shake back and forth, and another 9% or so is lost to friction.

 

[krab]

The actions are rotating loads. A motor that turns a load produces a rotating force, in other words a couple. This has to be compensated by an equal and opposite reaction, in this case a couple that turns the hovercraft in the opposite direction. That is the essence of the device. A motor turns a load; that makes the hovercraft turn in the opposite direction.

So you appear to believe in conservation of angular momentum. Why do you not believe in conservation of linear momentum? As for us, Would we believe that conservation of linear momentum is true, or would we believe that a guy who has filmed a jiggling vibrating assembly of parts has disproved it? Now that's a toughie.

 

[enigma]

Yes they do, they use reaction wheels to maintain their attitude. They don’t have to push against anything to do this.

No. Try again.

The satellite torques the wheel. The wheel torques the satellite. The wheel speeds up. The satellite changes orientation.

So you implicitly agree that a rotary means of propulsion is not only feasible, it is in fact used in space.

Changing orientations by adjusting the potential energies of internal components is NOT propulsion.

BTW it is an erroneous notion that propulsion has to push against something. When in space rockets simply throw away their burnt fuel in space against nothing. All you need is an action to get a reaction. Get your notions correctly!

The rocket pushes against the fuel. The fuel pushes against the rocket. You do realize you're accusing an aerospace engineer of not knowing how a rocket works, right?

That is a quagmire I do not wish to go into.

Then don't expect anyone to shill out millions of dollars to test your device, and don't expect any of us to believe you've invented an infinite improbability drive.

 

[Chronos]

BTW it is an erroneous notion that propulsion has to push against something. When in space rockets simply throw away their burnt fuel in space against nothing. All you need is an action to get a reaction. Get your notions correctly!

A refresher course in rocket science may be in order. A rocket pushes against the mass of the propellent being expelled. Your device is going to flop around like a wounded toad and whatever linear displacement you manage to coax out of it will require a huge amount of energy compared to a device such as a rocket.

 

[russ_watters]

The rocket pushes against the fuel. The fuel pushes against the rocket. You do realize you're accusing an aerospace engineer of not knowing how a rocket works, right?

...and a mechanical engineer of not understanding torque. And most of the rest of the guys who have posted in this thread are either physicists or engineers. In another universe, that would be funny...

Ray, it appears I was wrong - you need to learn what conservation of energy/momentum is, as well as how torques/couples work in machines. I had hoped you would know Newtonian mechanics - its learned in high school physics and should even be intuitive.

There is an enormous amount of information on the internet about these two subjects. Please, please avail yourself of the resources and learn about these two concepts. Google works: http://www.mcasco.com/QA15.html is a start.

To help you think about the rocket situation you mentioned in your email we need to talk a bit about cause and effect. The conservation of linear momentum is one of those things very near to the heart of what makes the universe work. For our purposes it is a cause, not an effect. That means we do not say linear momentum is conserved because... Rather we say this or that happens because linear momentum is conserved. If we take the conservation of linear momentum to be a "law of nature" then we can conclude all sorts of interesting things from that.

Suppose for example that we have a rocket loaded with fuel, initially at rest in our frame of reference. When we start the engines, some of the fuel is ejected at high speed from the exhaust of the rocket. The exhausted fuel now has some linear momentum in our reference frame. The total linear momentum before the firing of the engines was zero. Since it is conserved, the total must remain zero. This means that the momentum of the fuel in the backward direction must be exactly balanced by the momentum of the rocket in the forward direction. Therefore the rocket moves forward.

This concept applies to your hovercraft as well - it moves forward, therefore something else must move in the other direction, or it must push against the table. Take your pick.

For the concept of a "couple" vs a "torque", look http://www.engin.brown.edu/courses/en3/Notes/Statics/Forcecouple/Forcecouple.htm. You're misusing the concepts.

We have seen that a force acting on a rigid body has two effects: (i) it tends to move the body; and (ii) it tends to rotate the body.

A natural question arises – is there a way to rotate a body without moving it? And is there a kind of force that causes only rotation without translation?

The answer to both questions is yes.

5.1 Force couples

A system of forces that exerts a resultant moment, but no resultant force, is called a force couple.

Couples cannot cause translational motion - but then, what is happening on your device isn't couples anyway - its torques.

 

[russ_watters]

Ray, in my searches, I have found you have discussed this at length on other forums. The answers the scientists and engineers are giving you on other forums are the same as the answers we are giving you. I really need to know: is there anything that any expert can tell you that would convince you that your device is moving because of something other than "reaction torque propulsion"? If not, its useless to continue trying to explain it to you.

Or, failing that, how many experts does it take before you will believe one?

Further, you clearly have put a lot of energy into this - put some energy into learning the physics and engineering behind it.

 

[mapper]

shesh, when this gets locked "Theory vs. Math (possible/impossible)" is the only thead people are going to be able to post in!

wtf is up with all the locked threads anyway? Let people post if they wish. If its dead it will die on its own!

 

[enigma]

wtf is up with all the locked threads anyway? Let people post if they wish. If its dead it will die on its own!

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[Doc Al]

And on that note: thread closed.