Merged DDWFTTW in a “Real” Wind

[windgrins]

Yes, such a comparison would be nonsense, and that is probably why I never made any such comparison. What I did compare was the treadmills themselves, making the observation that the modified "force treadmill" largely eliminates belt variations due to the belt itself (with nobody walking on it) going around the end cylinders. The variations would be tiny, and are of no concern during normal treadmill usage, but may be large enough to influence the behaviour of the equally tiny cart on the belt. It is possible that very slight back and forth accelerations on the belt may act in the manner of a vibratory conveyor, in sending the cart up the belt. It is a possibility that cannot be discounted.




As evidence of DDWFTTW? No I would not. If there can be assurance the belt is not under going any accelerations at all, I would have to discount the possibility of the cart being shuffled up the belt due to such accelerations. That still would not convince me of the treadmill equivalency because a power analysis says the cart cannot power itself up the belt, powered by the belt in any normal fashion. If the "vibratory conveyor" possibility is eliminated, then I would have to consider other possibilities.
I have already alluded to one of those possibilities when I pasted that photo of the (cylindrical) lawn mower. If you have ever used one you would know that sometimes when you push on it, instead of cutting the grass it rides up over the top of the grass. The wheels still spin and the cylinder still spins but it is cutting no grass and it is much easier to push than when it is cutting. The cart, after being held on the belt and allowed to spin up and develop thrust, can be doing something similar to that lawn mower. It can just be scooting along the belt, very lightly in contact with the belt, running on the built-up thrust and only gaining a tiny bit of energy from the belt to keep the thrust topped up, so to speak. It is not rolling up the belt and drawing full power and thus feeling full drag, just lightly riding over the top of the belt in a similar manner to the lawn mower that has ridden up on the grass. It is a possibility that should be investigated. Perhaps a strobe light would shed a bit of light on the issue?

To your first paragraph, multiple carts on multiple treadmills built by multiple observers with completely different modes of vibrations does in fact eliminate this as a reasonable hypothesis of cart transport. If you had ever done any vibration analysis, you would be very convinced that this is not a viable theory. Different styles of functioning carts all only share one common trait, once they achieve a certain propeller speed (slightly different for each cart which reflects minor build differences), they all go up the treadmill at any speed of the treadmill above that speed. This alone eliminates the vibration analysis theory since these vastly different carts will have totally different modes of resonant frequencies. (incidentally, since the belt does not change speed in any continuous way, you could indeed characterize this as a "vibration hypothesis" as vibration is small positive and negative accelerations.)


The lawnmower seems to be a rather tortured comparison. When someone is pushing it you basically just stated that it is easier to push when it is not doing the work of cutting the grass!

No disagreement here but I can't see your analogy in any way that this relates to the cart.

It doesn't do your credibility any good the way you duck and weave on the TM questions. You make a lot of posts when you think you have a point but you go awfully silent when someone asks a simple question which shoots that point completely down. It's certainly hard to entertain other far-fetched theories when you won't respond to defend your points on the simpler ones.

WindGrins

 

[humber]

If you had ever done any vibration analysis, you would be very convinced that this is not a viable theory.

Meaning that you haven't, but would like to suggest that you have.

Different styles of functioning carts all only share one common trait, once they achieve a certain propeller speed (slightly different for each cart which reflects minor build differences), they all go up the treadmill at any speed of the treadmill above that speed.
This alone eliminates the vibration analysis theory since these vastly different carts will have totally different modes of resonant frequencies. (incidentally, since the belt does not change speed in any continuous way, you could indeed characterize this as a "vibration hypothesis" as vibration is small positive and negative accelerations.)
The lawnmower seems to be a rather tortured comparison. When someone is pushing it you basically just stated that it is easier to push when it is not doing the work or cutting the grass!
No disagreement here but I can't see your analogy in any way that this relates to the cart.

It is certain that a cart cannot travel up the belt by conventional rolling. That is not possible because of energy constraints and some mechanical matters around rolling. That idea is a non-starter.

But, it is possible that if there are adequate levels of vibration, the cart could run on that energy which is not strictly related to the linear motion of the belt. That energy could drive the cart if the power levels are low.
It is possible to keep a cart at "windspeed" using 100mW. (0.1W), and maybe less. Resonance could work over a wide range of frequencies. There are remote sensors which operate on the electrical power derived from vibration, and that vibration can be "random" or spectrally limited.

Another is possibility is the small accelerations of the belt, the belt us then like a vibratory conveyor. The cart is initialized by first allowing it to spin up by being held in the hand.

And then there is the analogy of the lawnmower. That definitely works, and I am sure will work on a completely smooth and steady belt.

A propeller under static or near-static conditions, will consume power that is related solely to its AV.
Control that, or how much time the wheel spends actually driving the prop, and the rest follows.

Drela gives an example of a 1.8W prop producing 1N thrust. The belt is 5m/s, so the belt drag is 1.8W/5m/s = 0.36N

"P = sqrt[ T^3 / (2 rho pi) ] / (eta_h R)
T = thrust
rho = air density
pi = 3.14159
eta_h = hover figure of merit = hover efficiency ( = 0.8 typically)
R = rotor radius

F = P / V

V = 5 m/s = 11 mph (looks like the speed of the cart)
T = 1 N (102 grams)
R = 0.4 m
eta_h = 0.5 (assume crummy prop to be conservative)
rho = 1.2 kg/m^3

This gives the following prop shaft power P = 1.8W

The power-generating force on the wheels is:

F = P/V = 1.8 W / 5 m/s = 0.36 N

T_net = T - F = 1.0N - 0.36N = 0.64 N = 65 gram = 2.3 oz"

But, what if the same prop AV were maintained, and so the 1.8W, but the belt were 10m/s? To keep the same prop AV, double the wheel radius, then wheel drag will be 0.18N. P = 0.18*10m's = 1.8W.

The faster the belt, the lower the drag. It stands to reason then, that the first cart could function, if it spent less time connected to the faster belt, or was already doing so on the 5m/s belt.

 

[windgrins]

Your problem now, not mine!

Meaning that you haven't, but would like to suggest that you have.



It is certain that a cart cannot travel up the belt by conventional rolling. That is not possible because of energy constraints and some mechanical matters around rolling. That idea is a non-starter.

But, it is possible that if there are adequate levels of vibration, the cart could run on that energy which is not strictly related to the linear motion of the belt. That energy could drive the cart if the power levels are low.
It is possible to keep a cart at "windspeed" using 100mW. (0.1W), and maybe less. Resonance could work over a wide range of frequencies. There are remote sensors which operate on the electrical power derived from vibration, and that vibration can be "random" or spectrally limited.

Another is possibility is the small accelerations of the belt, the belt us then like a vibratory conveyor. The cart is initialized by first allowing it to spin up by being held in the hand.

And then there is the analogy of the lawnmower. That definitely works, and I am sure will work on a completely smooth and steady belt.

A propeller under static or near-static conditions, will consume power that is related solely to its AV.
Control that, or how much time the wheel spends actually driving the prop, and the rest follows.

Drela gives an example of a 1.8W prop producing 1N thrust. The belt is 5m/s, so the belt drag is 1.8W/5m/s = 0.36N

"P = sqrt[ T^3 / (2 rho pi) ] / (eta_h R)
T = thrust
rho = air density
pi = 3.14159
eta_h = hover figure of merit = hover efficiency ( = 0.8 typically)
R = rotor radius

F = P / V

V = 5 m/s = 11 mph (looks like the speed of the cart)
T = 1 N (102 grams)
R = 0.4 m
eta_h = 0.5 (assume crummy prop to be conservative)
rho = 1.2 kg/m^3

This gives the following prop shaft power P = 1.8W

The power-generating force on the wheels is:

F = P/V = 1.8 W / 5 m/s = 0.36 N

T_net = T - F = 1.0N - 0.36N = 0.64 N = 65 gram = 2.3 oz"

But, what if the same prop AV were maintained, and so the 1.8W, but the belt were 10m/s? To keep the same prop AV, double the wheel radius, then wheel drag will be 0.18N. P = 0.18*10m's = 1.8W.

The faster the belt, the lower the drag. It stands to reason then, that the first cart could function, if it spent less time connected to the faster belt, or was already doing so on the 5m/s belt.

Since I have performed vibration analyses, I am confident of what I speak. (While I'm on this topic, I would like to use it as an example of problems which are much easier to deal with in one domain vs another and yet the two have to be consistent. Vibration is usually much more easy to deal with in the frequency domain than the time domain. PPG should note this about a force analysis verses a power analysis.)

We welcome any of you demonstrating any of the proposed modes of cart functioning that you allege. The ball is in your cart now. The theory and demonstrations have been established. It's up to you to show us differently.

I would definitely suggest you put a push mower on a treadmill and video it so we can watch it go up treadmill. Do you think you can make it work with a bald treadmill or will you have to get a good patch of grass established on the belt? Try not to let it run you over if you stand at the rear of the TM!

None of your objections have withstood scrutiny to date. So far they are clearly unworkable and nonsense. They have now served the purpose of ferreting out and illustrating how the cart works and how well they work. They are fundamentally a tribute to Spork and JB. (Kudos to Llyricist for all the mathy bits too!) Congratulations on being such excellent deniers. I personally could never have thought up so many silly theories and absurd strawmen. You've done a great job! I now think I will just ignore any of your and PPG's post that lack merit! Enjoy!

WindGrins

 

[humber]

Since I have performed vibration analyses, I am confident of what I speak.

Then the vibration model should not in the least surprise you.
Do tell of the analysis that you have performed.
And the quick wiki means what? Force is not measured, acceleration is.

We welcome any of you demonstrating any of the proposed modes of cart functioning that you allege. The ball is in your cart now. The theory and demonstrations have been established. It's up to you to show us differently.

You have no TM analysis at all. If the claim of real wind equivalence were correct, then Drela's example confounds it.

The power consumed is 1.8W, the thrust is 1N, and the belt speed is 5m/s. A cart traveling at 5m/s on 1N would need P = 1N*5m/s = 5W.

The net force is 1N -0.36N = 0.64N. Spork's cart is 0.16kg, so
a = 0.64N/0.16kg = 4ms-2. Not seen. A steady crawl at ~0.1m/s.

None of your objections have withstood scrutiny to date. So far they are clearly unworkable and nonsense. They have now served the purpose of ferreting out and illustrating how the cart works and how well they work. They are fundamentally a tribute to Spork and JB.
WindGrins

You have done absolutely nothing to refute anything said, but simply offered that the video proves it, but they tend show that the cart is doing nothing of interest, and mostly sliding.
When prodded with a fork or finger, the cart slides back and continues to do so after the stimulus has stopped, it loses momentum, regains it, and moves forwards again. It often drifts down the belt and slides left and right.

 

[windgrins]

Ball of proof of denial in your court!

Then the vibration model should not in the least surprise you.
Do tell of the analysis that you have performed.
And the quick wiki means what? Force is not measured, acceleration is.


You have no TM analysis at all. If the claim of real wind equivalence were correct, then Drela's example confounds it.

The power consumed is 1.8W, the thrust is 1N, and the belt speed is 5m/s. A cart traveling at 5m/s on 1N would need P = 1N*5m/s = 5W.

The net force is 1N -0.36N = 0.64N. Spork's cart is 0.16kg, so
a = 0.64N/0.16kg = 4ms-2. Not seen. A steady crawl at ~0.1m/s.


You have done absolutely nothing to refute anything said, but simply offered that the video proves it, but they tend show that the cart is doing nothing of interest, and mostly sliding.
When prodded with a fork or finger, the cart slides back and continues to do so after the stimulus has stopped, it loses momentum, regains it, and moves forwards again. It often drifts down the belt and slides left and right.

It doesn't surprise me in the least that you and PPG came up with a nonsense vibration hypotheses. You have that right!

I would definitely suggest you put a push mower on a treadmill and video it so we can watch it go up treadmill. Do you think you can make it work with a bald treadmill or will you have to get a good patch of grass established on the belt? Try not to let it run you over if you stand at the rear of the TM!

None of your objections have withstood scrutiny to date. So far they are clearly unworkable and nonsense. They have now served the purpose of ferreting out and illustrating how the cart works and how well they work. They are fundamentally a tribute to Spork and JB. (Kudos to Llyricist for all the mathy bits too!) Congratulations on being such excellent deniers. I personally could never have thought up so many silly theories and absurd strawmen. You've done a great job! I now think I will just ignore any of your and PPG's post that lack merit!

We welcome any of you demonstrating any of the proposed modes of cart functioning that you allege. The ball is in your cart now. The theory and demonstrations have been established. It's up to you to show us differently.

WindGrins

 

[humber]

It doesn't surprise me in the least that you and PPG came up with a nonsense vibration hypotheses. You have that right!

I would definitely suggest you put a push mower on a treadmill and video it so we can watch it go up treadmill. Do you think you can make it work with a bald treadmill or will you have to get a good patch of grass established on the belt? Try not to let it run you over if you stand at the rear of the TM!

More fluff.

None of your objections have withstood scrutiny to date. So far they are clearly unworkable and nonsense. They have now served the purpose of ferreting out and illustrating how the cart works and how well they work. They are fundamentally a tribute to Spork and JB. (Kudos to Llyricist for all the mathy bits too!) Congratulations on being such excellent deniers. I personally could never have thought up so many silly theories and absurd strawmen. You've done a great job! I now think I will just ignore any of your and PPG's post that lack merit!

A simple sail can do what the BB does, while taking only 10% of the available wind energy, and not 200%.
You do like to ignore the fact that the wind was measured at hub height, but the prop turns into air, 2.5m above that. It's not a record at all.

We welcome any of you demonstrating any of the proposed modes of cart functioning that you allege. The ball is in your cart now. The theory and demonstrations have been established. It's up to you to show us differently.[/B]
WindGrins

It seems that you are lost for any cogent response, but to repeat that you are satisfied.

 

[windgrins]

Cogent Response-Much more cogent than yours!

Here's my very cogent response:

None of your objections have withstood scrutiny to date. So far they are clearly unworkable and nonsense.

We welcome you demonstrating any of the proposed modes of cart functioning that you allege. It's up to you to show us differently.

I will just ignore any of your and PPG's post that lack merit!


Folks, can you help me generate a list of Humber proposed mechanisms for the cart function. I can think of the following easily:

Tacking props
Tacking uprights
Stored KE
Shifting Winds
Prop is a turbine
Vibration Theory of TM
KE comes from initial push
Lawnmower Theory
Treadmill provides energy unlike real world.
Cheating and Fraud with NALSA being duped idiots.

We welcome you demonstrating any of the proposed modes of cart functioning that you allege. It's up to you to show us differently.

WindGrins

 

[humber]

Here's my very cogent response:

None of your objections have withstood scrutiny to date. So far they are clearly unworkable and nonsense.

Oprah.

We welcome you demonstrating any of the proposed modes of cart functioning that you allege. It's up to you to show us differently.

"I have no idea how the TM works, and hope Humber doesn't. Upon that basis I will sustain my position behind the parapet"

I will just ignore any of your and PPG's post that lack merit![/B]
WindGrins

One could hardly expect anything less.

I would definitely suggest you put a push mower on a treadmill and video it so we can watch it go up treadmill. Do you think you can make it work with a bald treadmill or will you have to get a good patch of grass established on the belt? Try not to let it run you over if you stand at the rear of the TM!

http://www.youtube.com/watch?v=dgHBDESd38M&feature=related

 

[windgrins]

"I have no idea how the TM works, Upon that basis I will sustain my position"

We welcome you demonstrating any of the proposed modes of cart functioning that you allege. It's up to you to show us differently.

I will just ignore any of your and PPG's post that lack merit!

I may choose to respond if you ever make a post that has any merit!

WindGrins

 

[Subduction Zone]

humber, do you understand what was happening in DDWFTTW #6? I am willing to bet that that test went right over your head.

 

[windgrins]

Humber -Rocket Scientist!

humber, do you understand what was happening in DDWFTTW #6? I am willing to bet that that test went right over your head.

It doesn't take a rocket scientist to figure it out since its clearly labeled:

"A simple demonstration of our DWFTTW cart running unassisted for as long as we could managed to keep it on the treadmill."

Since Humber claims to be one, maybe that's why he doesn't get it!

This one falls in the category:

I will just ignore any of your and PPG's post that lack merit!

That video clearly lacked any merit in the point he was trying to make about a lawnmower falling off the back of a TM so it is appropriate to ignore!

This kind of response is going to be an incredible time saver for me!

WindGrins

 

[Subduction Zone]

Labeling does not help humber. Even with the label he probably would not have gotten that answer without outside help.

Okay question two for humber; why did the cart eventually fall off of the back of the treadmill and not move forward like it does in other videos?

 

[windgrins]

Labeling does not help humber. Even with the label he probably would not have gotten that answer without outside help.

Okay question two for humber; why did the cart eventually fall off of the back of the treadmill and not move forward like it does in other videos?

OK, I promise not to spoil the surprise before he gives up!

WindGrins

 

[nvidiot]

Can I ask a quick question? What happens if you run the small cart versions backwards on the treadmills? i.e. With the propellor at the front of the cart and the wheels at the back?

 

[Subduction Zone]

Can I ask a quick question? What happens if you run the small cart versions backwards on the treadmills? i.e. With the propellor at the front of the cart and the wheels at the back?

It still goes up the treadmill, let me see if I can find that test for you.

 

[Subduction Zone]

Doh! How could I have forgotten? That is the infamous Harold Bricer test.

http://www.youtube.com/watch?v=rb_4q2LSRsM

 

[nvidiot]

Thanks Subduction Zone.

 

[Subduction Zone]

That was probably the last test that spork did for a denier. No matter what test spork and JB the deniers, mainly humber and Harold Bricer at that time, simply denied the result. Harold and humber have never done their own experiments, nor would they specify a test where they would stick by the results. humber at best would propose a test that would break a cart and not prove anything, Harold, like a typical sore loser, would not propose any more tests or accept the results of any tests done.

 

[RossFW]

Still no video from Humber then? You all realise he first said he would produce one "Soon" THREE YEARS AGO!!

 

[RossFW]

Harold, like a typical sore loser, would not propose any more tests or accept the results of any tests done.

More to the point, he once was actually cajoled into agreeing to admit error if the BB went DDWFTTW. After it did, he tried humber arguments for a while, then just stopped posting. i actually PMed him as he assured everyone the trials would never happen, just to point at he was at leat wrong about THAT- never heard from him again....