DDWFTTW Turntable Test: 5 Min Video - Is It Conclusive?

[vanesch]

In order to understand the non-stored forces at work on the cart at wind=0 we have to imagine a "virgin" situation where the propeller is not in motion at all. Not rotating.

Wind speed = 0

Ground speed = say, 10mph but contrary to the direction we want the cart to accelerate into

Prop rotation speed = 0

Is there a total force on the cart here in the right direction that will cause acceleration in the right direction?

I think in the crude model I pointed to before (the 3 forces: prop force, air drag and wheel resistance), you can put K = 0 (gearing ratio 0) and then what remains is simply the drag term.

F_tot = rho_air x S x K x v_cart x ((K-1) x v_cart + v_wind) + W x (v_wind - v_cart)^3 - ...

... rho_air x S x K x ( (K^2-1) x v_cart^2 + 2 x v_cart x v_wind - v_wind^2)


So fill in K = 0 (gearing ratio 0, the propeller doesn't turn, no matter the wheel turning):

F_tot = W x (v_wind - v_cart)^3

Don't forget that the velocities here were originally expressed in the "floor" frame. However, as this is a difference of velocities, it is simply the air speed wrt the cart, and it doesn't matter where you calculate it.

 

[ThinAirDesign]

Wow -- watching this thread has been an absolute blast.

While giving swerdna props for his turntable, as expected it didn't convince anyone of DDWFTTW who already understands basic physics. Vanesch did a great job of explaining how a simple tilt of the treadmill proves the 'steady state' claim without all the rotational complications.

swerdna says that every test he has done confirms our DDWFTTW conclusions -- I'm glad he convinced himself. We didn't necessarily predict what his position would be in the end, but we certainly perfectly predicted the outcome of his tests before he performed them.

What I did find entertaining was how swerdna resisted performing Schroder's tests until he could understand what Schroder was testing for and what different results would mean. swerdna of course understands why I find that entertaining -- it's the same routine I went through with him before he built his own test rig. Being on the other end of that treatment is always educational.

Schroder was the same as ever -- starting with an 'over-unity' assumption and then ignoring everything not compliant with that position ... and in the end, against overwhelming evidence and reason, claiming fraud and and an "Academy" that claims DDWFTTW is nonsense. No evidence or course ... just claims.

Vanesch and JeffR -- amazing patience. Kudos.

JB

 

[A.T.]

In order to understand the non-stored forces at work on the cart at wind=0 we have to imagine a "virgin" situation where the propeller is not in motion at all. Not rotating.

Forces cannot be stored. You are confusing stuff again (forces and energy I guess). And by stored energy you mean the rotational kinetic energy of that ultralight plastic propeller? Well, since the wheels are still turning, they also have rotational kinetic energy stored in the "virgin situation" you describe.

But can you have your "virgin situation" in the Brennan torpedo. Initially the propeller is not moving and the torpedo has the same speed as the water(=~air). Then when the wires(=~ground) start to move relative to the water(=~air), the propeller spins up and accelerates the torpedo to 30mph beyond water speed(~=wind speed) in the wire's(=~ground's) frame. And then it goes for 2000 yards underwater, certainly not on energy stored in the propellers.

 

[swerdna]

What I did find entertaining was how swerdna resisted performing Schroder's tests until he could understand what Schroder was testing for and what different results would mean. swerdna of course understands why I find that entertaining -- it's the same routine I went through with him before he built his own test rig. Being on the other end of that treatment is always educational.

JB

Big difference being however that I actually conducted the test Schroder requested and quickly gave him the results. Also offered to conduct any other test Schroder or anyone else wants done on my turntable.

 

[zoobyshoe]

Ok I think I misunderstood what you were trying to get at here. You want the wind at zero and the cart is moving in the negative direction correct. Well you might have to modify the design but you could make it take power from the wheels to help it more rapidly reach the wind speed (that is to stop). It's already been established that this thing can't go faster than the wind if the wind speed is too low. No it can't sustain faster than wind speed in zero wind, nobody ever claimed it could.

I think I need to poll the adherents of the cart and make sure I understand what amount of stored energy the criteria allow. You can't accelerate the cart without giving it some momentum including the momentum of the prop, gearbox, and wheels. It is therefore possible to "optimize" the power storage to the point where whether or not you're violating the "powered only by the wind" part is a value judgment. Why can't we charge up a battery from a wind turbine and use that to power an electric motor to send the cart zipping downwind faster than the wind? That's powered "only by the wind".

 

[ThinAirDesign]

Big difference being however that I actually conducted the test Schroder requested and quickly gave him the results.

That certainly is one big difference between you and I -- you will do tests that make sense to the requester and not to you.

Also offered to conduct any other test Schroder or anyone else wants done on my turntable.

We have made the same offer and have followed through repeatedly -- we of course require the the user be able to justify the results of the test as something of additive value to our library of videos. As you concluded with your 'why are you attempting to use non-equivelancy in an attempt to prove equivelancy" comment back to Schroder, his test was useless, poorly conceived and did nothing to lead him towards the truth.

If you ever become 100% convinced of the validity of your testing and the DDWFTTW testing I suspect you will grow tired after about the 100th request for some cockimamy usless test. I understand that you have your doubts ... we understand the device and thus don't have doubts. That delta simply leaves you vulnerable to testing requests that lead nowhere.

I'm aware that outdoor tests have been done but they seem to be very rare and poorly conducted.

With the time and energy people put into a number of forums to debate this issue they could have built and tested an outdoor cart.

C'mon now swerdna -- that's just a silly question considering both the time you have put into various forums and the time you spend making your turntable rig. The above fingerpointing only leaves you with four fingers pointed back at yourself -- **Why didn't YOU build and test and outdoor cart rather spending time on the forums and rather than building your turntable?**

Check those four fingers and I suspect you'll have the answer to your own question.

JB

 

[ThinAirDesign]

I think I need to poll the adherents of the cart and make sure I understand what amount of stored energy the criteria allow. You can't accelerate the cart without giving it some momentum including the momentum of the prop, gearbox, and wheels. It is therefore possible to "optimize" the power storage to the point where whether or not you're violating the "powered only by the wind" part is a value judgment. Why can't we charge up a battery from a wind turbine and use that to power an electric motor to send the cart zipping downwind faster than the wind? That's powered "only by the wind".

Zoo, here is our claim:

"Directly downwind, faster than the wind, powered only by the wind, steady state."

Your 'turbine, battery and motor' fail the "steady state" portion of the requirement.

No matter how much rotational mass a device has, if it's operating steady state that mass isn't being used to motivate it.

JB

 

[cesiumfrog]

The above fingerpointing only leaves you with four fingers pointed back at yourself

four?

 

[zoobyshoe]

Forces cannot be stored. You are confusing stuff again (forces and energy I guess). And by stored energy you mean the rotational kinetic energy of that ultralight plastic propeller? Well, since the wheels are still turning, they also have rotational kinetic energy stored in the "virgin situation" you describe.

Indeed, I allowed myself once again to slip into a non-rigorous use of terms.

But can you have your "virgin situation" in the Brennan torpedo. Initially the propeller is not moving and the torpedo has the same speed as the water(=~air). Then when the wires(=~ground) start to move relative to the water(=~air), the propeller spins up and accelerates the torpedo to 30mph beyond water speed(~=wind speed) in the wire's(=~ground's) frame. And then it goes for 2000 yards underwater, certainly not on energy stored in the propellers.

I am ignoring the torpedo altogether at this point. Vanesh has already offered a comprehensive test of one's ability to analyze different frames, which I have also put on hold.

As I said earlier:

...the zoobie brain is a slow, rust-encrusted, squealing, steam- emitting, gear-grinding, contraption with lots of loose hoses and shorted wires, and no one remembers the last oil change.

 

[ThinAirDesign]

four?

Would you buy dislocated thumb? LOL

JB

 

[OmCheeto]

...here is our claim:

"Directly downwind, faster than the wind, powered only by the wind, steady state."

Do you have evidence of this?

 

[M Grandin]

Differential on a rail ...

I think you are discussing this issue in a wrong way, as it appears impossible convince "schröder & Co" in this specific example. Instead you could discuss this in more general terms: Is it generally possible drive something faster than (and by help from) a surrounding medium? A propeller in air is somewhat "fuzzy" and invites to fuzzy arguing.

Let us assume a long rail resting on ground and a second moving rail at velocity Vo parallell to this. Is it possible make a wagon that is driven faster than Vo on these rails? Yes it must be: Assume a differential (such that is used in car transmission) and orient it so it acts as difference gearing unit C = A - B , where A is rotation speed of wheel on fixed rail,
B is rotatiton speed of wheel on moving rail and C is resulting speed of shaft out from the differential. (Let us for simplicity call rotation speed of shaft corresponding to velocity Vx
also Vx - to simpify this hasty text).

Now you get C = Vo out from the differential whatever speed V the cart has and at the torque and power the moving rail can deliver. And moreover: Towing this cart on rail doesn't require any force or power whatever the torque at C is. So whatever speed the cart has, rolling on the rails, the power and torque from C-shaft can be used to accelerate the cart further. If Einstein admitted, it could even reach light velocity.

In this example the C-shaft should be suitibly geared and loosely coupled to wheel on rail
to accelerate cart to not lock the system.

If you replace the B-wheel by propeller and moving rail by wind you in essens hould have the DDWFTTW vehicle.

I thought this out myself, but may have read about aquainted earlier.

 

[zoobyshoe]

Zoo, here is our claim:

"Directly downwind, faster than the wind, powered only by the wind, steady state."

Your 'turbine, battery and motor' fail the "steady state" portion of the requirement.

No matter how much rotational mass a device has, if it's operating steady state that mass isn't being used to motivate it.

JB

Thanks!

 

[swerdna]

That certainly is one big difference between you and I -- you will do tests that make sense to the requester and not to you.



We have made the same offer and have followed through repeatedly -- we of course require the the user be able to justify the results of the test as something of additive value to our library of videos. As you concluded with your 'why are you attempting to use non-equivelancy in an attempt to prove equivelancy" comment back to Schroder, his test was useless, poorly conceived and did nothing to lead him towards the truth.

If you ever become 100% convinced of the validity of your testing and the DDWFTTW testing I suspect you will grow tired after about the 100th request for some cockimamy usless test. I understand that you have your doubts ... we understand the device and thus don't have doubts. That delta simply leaves you vulnerable to testing requests that lead nowhere.



C'mon now swerdna -- that's just a silly question considering both the time you have put into various forums and the time you spend making your turntable rig. The above fingerpointing only leaves you with four fingers pointed back at yourself -- **Why didn't YOU build and test and outdoor cart rather spending time on the forums and rather than building your turntable?**

Check those four fingers and I suspect you'll have the answer to your own question.

JB

Unlike yourself and Spork I certainly don’t think I know it all and will happily listen to others and carry out their tests in an attempt to understand their case.

I only belong to two forums (hardly various) and have only been involved with this debate since November 2008. Since then (even with a 3 week overseas holiday) I have constructed and tested several carts and the turntable. How many years (3? - 6? - more?) and how many forums (6? - 10? - more?) have Spork & Co been involved with this debate and what have they achieved? They didn’t come up with the principle as it has been known of for years (Brennan, Bauer, Robinson). The “Spork” cart is a direct copy of someone elses design and this person also used a treadmill for testing.

I have built and tested on a turntable to answer the main question I had that the cart on the treadmill might be storing energy that it was losing too slowly to be shown on a treadmill. That question has been answered well enough for myself and I now believe DDWFTTW is possible. I don’t neeed to build and conduct “real wind” tests but am planning to do so as further confoirmation for myself and to hopefully help others. I will video and publish all tests I conduct (watch this and the other space).

I really have no idea why you have bought your childish, unsubstantiated attacks against myself to this forum or why you even continue them on the other. Hardly the actions of a person of science. In future I will not reply to any of your posts as well as Sporks. You can continue your unsubstantiated personal attacks against myself to your heart’s desire.

To suggest a use for the fifth digit would be too easy.

 

[atyy]

Your 'turbine, battery and motor' fail the "steady state" portion of the requirement.

Why does it fail the "steady state" portion? I would think it passes that, but fails a requirement that not only the centre of mass, but also the boundary of the vehicle move faster than the wind relative to the ground? Actually, I liked the example, because it shows that energy is not the issue.

 

[rcgldr]

Is it generally possible drive something faster than (and by help from) a surrounding medium?

Already covered along with a link to a video in this post:

Have you seen the motor car that goes faster than the ruler video? It seems to be somehow related to these FTTW devices.
http://www.youtube.com/watch?v=9Yt4zxYuPzI&feature=channel

 

[rcgldr]

claim: "Directly downwind, faster than the wind, powered only by the wind, steady state."

Powered by the difference between wind speed and ground speed, not just the wind. Also to eliminate frame of reference issues, I've restated this as:

|v_cart-v_ground| > |v_wind-v_ground|

(where |...| means magnitude of the expression inside).

Do you have evidence of this?

That's what the videos demonstrate. A simplified description is that you have a forward force between prop + air, and an opposing force relative to the torque of the prop between wheels + ground. Because of the tailwind situation, using the cart's frame of reference, the relative speed of the air is less than the speed of the ground, so this allows the prop parameters (pitch and diameter) plus any effective gearing to be configured to generate more thrust than opposing force from the wheels, but at a lower than ground speed. The force at the prop is higher than the opposign force at the ground, but the power output at the prop is less because of the reduced speed of that thrust.

 

[rcgldr]

I think I need to poll the adherents of the cart and make sure I understand what amount of stored energy the criteria allow.

There isn't any restriction regarding stored energy with theoretical devices used to explain the possibility. For the actual carts made, a "steady state" only occurs at terminal velocity and requires that the wind to ground speed remains constant. In an outdoor situation, the varying wind versus ground speed would result in the cart oscillating between coast (momentum) mode and powered mode. If the wind is reasonably steady, then the average |v_cart-v_ground| > |v_wind - v_ground|.

You can't accelerate the cart without giving it some momentum.

The momentum exchange is the result of slowing the wind. The momentum of the downwind air is reduced in order to increase the momentum of the cart. The ground also gets an increase in momentum, but since it mass is huge compared to the cart the cart ends up with most of the change in speed. The math for this involves noting that total energy and total momentum of the air + cart + ground system remain constant.

 

[zoobyshoe]

Zoo, here is our claim:

"Directly downwind, faster than the wind, powered only by the wind, steady state."

Your 'turbine, battery and motor' fail the "steady state" portion of the requirement.

No matter how much rotational mass a device has, if it's operating steady state that mass isn't being used to motivate it.

JB

There isn't any restriction regarding stored energy with theoretical devices used to explain the possibility. For the actual carts made, a "steady state" only occurs at terminal velocity and requires that the wind to ground speed remains constant. In an outdoor situation, the varying wind versus ground speed would result in the cart oscillating between coast (momentum) mode and powered mode. If the wind is reasonably steady, then the average |v_cart-v_ground| > |v_wind - v_ground|.

OK. I was afraid of this.

 

[OmCheeto]

That's what the videos demonstrate.

Which video's? Like swerdna, I've seen lots of them. I've yet to see any evidence that the air alone can push a cart faster than itself.

A simplified description is that you have a forward force between prop + air, and an opposing force relative to the torque of the prop between wheels + ground. Because of the tailwind situation, using the cart's frame of reference, the relative speed of the air is less than the speed of the ground, so this allows the prop parameters (pitch and diameter) plus any effective gearing to be configured to generate more thrust than opposing force from the wheels, but at a lower than ground speed. The force at the prop is higher than the opposign force at the ground, but the power output at the prop is less because of the reduced speed of that thrust.

That doesn't sound very simplified to me.

 

[cesiumfrog]

Swerdna, that turntable video is awesome.

Does anybody here disagree (with M Grandin) that a "passive" car between two rails (that move at some speed relative to each other) can use the relative motion to move itself faster still? ThinAirDesign? Omcheeto?

 

[zoobyshoe]

Swerdna, that turntable video is awesome.

Does anybody here disagree (with M Grandin) that a "passive" car between two rails (that move at some speed relative to each other) can use the relative motion to move itself faster still? ThinAirDesign? Omcheeto?

This seems to be the same situation as the "faster than the ruler" youtube.

 

[cesiumfrog]

This seems to be the same situation as the "faster than the ruler" youtube.

Thanks for directing me to that! Now, is it worth replacing the ruler (and corresponding wheel) with a movable tray of water (a fluid and a little paddle-wheel propeller)?

Or should we just give up on trying to change people's beliefs?

 

[ThinAirDesign]

Powered by the difference between wind speed and ground speed, not just the wind.

That's fine if you wish to make that your claim, but that's a re-wording that I'm unwilling to make on ours. If "powered by the wind" isn't good enough for our claim, it isn't good enough for sailboats or wind turbines or kites or, or, or. All those are wind powered just like the cart on the treadmill

JB

 

[ThinAirDesign]

Which video's? Like swerdna, I've seen lots of them. I've yet to see any evidence that the air alone can push a cart faster than itself.

Well, if you've watched swerdna's, let alone ours (search Spork33), you've seen plenty of not just "evidence", but it actually happening.

Now, I understand that you have been unable to grasp the application of Galilean relativity from the street to the treadmill, but that inability doesn't change what's really happening.

JB

 

[ThinAirDesign]

Does anybody here disagree (with M Grandin) that a "passive" car between two rails (that move at some speed relative to each other) can use the relative motion to move itself faster still? ThinAirDesign? Omcheeto?

Anytime there are two mediums with relative motion to each other it's possible to extract energy from that motion. That energy can be used for all sorts of things, including travel. Cleverly applied, travel faster than either medium can be accomplished.

Anyone who believes that moving through a current faster than the current isn't possible dare not get on a sailboat and sail downriver on a calm day (or upwind on a windy day) -- from the very valid perspective of the fish, a sailboat is going downcurrent faster than the current every time.

JB

 

[zoobyshoe]

I think I can hear PM's flying.

 

[ThinAirDesign]

Unlike yourself and Spork I certainly don’t think I know it all and will happily listen to others and carry out their tests in an attempt to understand their case.

There are many, many things I don't know -- how the DDWFTTW cart functions or how it will behave in any given testing scenario just happens not to be one of them.

The “Spork” cart is a direct copy of someone elses design ...

Not true -- though it certainly *is* quite similar -- and thus why we give credit.

... and this person also used a treadmill for testing.

That's certainly right -- there's no patent on Galilean relativity.

I really have no idea why you have bought your childish, unsubstantiated attacks against myself to this forum

Very strange Swerdna -- where's the "attack", and what exactly is "unsubstantiated"? While I was merely watching the thread and hadn't posted at all, you wonder why others (us) haven't built an outdoor version (in a manner belittling our use of our own free time) and yet you yourself chose not to build one, but to simply use the turntable design of another (Bauer) to test a cart design of another.

There's absolutely no shame in that as long as credit is given to those who have gone before. We give this credit ... in spite of your non-original work, you're not so free with such credit. If you wish to demonstrate that this is unsubstantiated, simply produce a quote (from any forum) where you give credit to those who first designed and tested your setup.

Again, I find no shame in building and testing what others have already done -- it's just not cool to do so without giving credit. We did our research -- we know as close as anyone who the originator of this design is and our primary video makes it crystal clear who's work we build on.

We in no way claim to be the first, I certainly hope you don't claim any sliver of it either -- even by omission.

JB

 

[ThinAirDesign]

I have posted the following numerous times when folks have difficulties with the treadmill as it relates to the creation of wind:

***************************
If you have a problem with the motor on the threadmill, you're only arguing about what creates the 'wind'.

There are two ways to create 'wind' -- move the air over the surface, or move the surface under the air.

Stand on the deck of an aircraft carrier in the dense fog -- stiff breeze flowing from bow to stern. Fly a kite. Set up a turbine powered generator. Listen to the repeated crack of the flag. Run a small land-yacht around on the deck. Test a DDWFTTW cart. Blow drifting bubbles with the kids. Hell, flood the deck and hold a tiny regatta with tiny sailboats.

Is there wind? Every wind powered device in the world says yes and behaves normally. How can you know?

Is the carrier:

A: sitting still in the ocean with a breeze blowing across it?
B: cruising on it's engines on a calm day?
C: floating engines off and drifting with a strong water current on a calm day?
D: sitting on a rollers with large electric motors winching it across the ground?
E: floating down a man made recirculating river where large electric pumps move the water?
F: inside a foggy wind tunnel where large electric fans create the wind?
G: I'm lying to you -- there is no carrier, just a giant treadmill with a carrier movie set on it.

It's a serious question and I'd love for those who think there is a difference between the street and the treadmill to answer it.

Let's invert that -- same deck, same fog, no wind. Flags don't flap. Bubbles don't drift. Wind turbine doesn't rotate. Is it calm, or is the carrier steaming with the wind? Or is the water drifting with the wind? Or is the wind tunnel turned off? Or is the carrier on rollers and being winched with the wind. You get the idea.

That's the entire point of Galilean relativity, something established without fail for four centuries now -- of two objects moving relative to each other, one can't tell which is 'moving' and which is 'still' without external reference -- reference wind carts and sailboats don't have.

JB

 

[rcgldr]

Anyone who believes that moving through a current faster than the current

Now, is it worth replacing the ruler (and corresponding wheel) with a movable tray of water (a fluid and a little paddle-wheel propeller)?

A DSFTTS (S = water stream) device was already covered in the posts about the Brennan torpedo, which able to achieve a speed of 31 mph forward in the water, with the power and steering coming from a pair wires being pulled backwards. This device was patented back in 1877 and later used by the military. It was a working example of a device that travels faster than the medium it flows through (water):

http://en.wikipedia.org/wiki/Brennan_Torpedo

Powered by the difference between wind speed and ground speed, not just the wind.

That's fine if you wish to make that your claim, but that's a re-wording that I'm unwilling to make on ours. If "powered by the wind" isn't good enough for our claim, it isn't good enough for sailboats or wind turbines or kites.

That's a common usage of the term "wind powered", all of those devices extract energy from the difference between wind speed and ground speed. However, gliders are also "wind powered", but there is no ground interface, except for a kite like launch. The wind power for gliders can be a simple updraft to oppose gravity, or it can be a wind shear boundary where the difference in wind speed across a thin shear boundary allows a radio control glider to achieve very high speed.

The simple updraft case:
http://www.youtube.com/watch?v=LUVRUMc7DP8&fmt=22

There are two ways to create 'wind' -- move the air over the surface, or move the surface under the air.

Or a third way, move air over air. The more complex wind shear case. In this video, the wind over the ridge is about 50 mph to 60 mph while the air behind and below the ridge is turbulent but around 0 mph. By circling across the shear boundary, the glider reaches a max radar speed of 333 mph. That same glider went 357 mph later in the day. The last I read the record was 365mph.

http://www.youtube.com/watch?v=Vi0hrjqU15I&fmt=18

My point is that wind powered doesn't always imply a ground interface. For gliders the ground interface is only used for kite like launches:

Kite like launch (full scale gliders can be similarly towed up by land vehicles):
http://www.youtube.com/watch?v=mkIIlO7Ckos&fmt=18