Down wind faster than the wind

[humber]

Humber, Thank you for the insight that a cart using a variable speed transmission can use stored energy in the propeller to propel itself to faster than wind speed. When you make your donation to JREF, please request that they post a note here stating that you have satisfied your obligation.

Of course, the rest of us have always been discussing a cart with fixed gearing and still claim that such a cart can be built that satisfies the claim. If you want to limit the claim to carts with fixed gearing I will permit you to do so. But the burden of proof as specified in the wager is, and always has been, yours.

Please point to the line where I say the cart has a "variable speed transmission". Unless accounted for, stored energy violates the requirement for steady state performance.

There are no physical differences between 'your' cart and mine. Same 1:1 ratio, same wheels, same propellor, same chassis, right down to the last nut and bolt of the published parts list. I have not seen Goodman's plans, but it looks to me like a bigger version if your cart.

 

[humber]

I would have thought the cover-charge for even entering this conversation was the understanding of the most basic principles of physics that go back 100's of years (or at least the willingness to learn them). Until humber completely understands and accepts the principle of equivalency of inertial frames what could there possibly be to debate with him?

Pensive.
Still not getting it. It's not equivalency that is wrong, but you.

 

[spork]

It's not equivalency that is wrong, but you.

At least you still have your sense of humor. That's important.

 

[humber]

At least you still have your sense of humor. That's important.

Even more pensive!

 

[John Freestone]

I think there is only one result that would take him down... and that is none of us responding to his trolling (and therefore ruining) of this thread.

You're right. Trouble is, troll posts are so hard to resist. No chance for that earlier suggestion of seeing if he could be banned from the thread, is there? This is just insane.

 

[ThinAirDesigns]

Humber:

...I am not going to offer such a test until you can tell me how you would plan to perform it.

As if we needed anymore evidence that this guy is flat out whack! LOL

He won't tell me the test until I tell him how I plan to perform the test that he hasn't told me about. ROFLAO!!!

You are an absolute master of nonsense humber.

JB

 

[Christian Klippel]

Ode to humber

<Singing along the melody of Bob Dylan's Blowing In The Wind>

How many treadmills must we have move on,
before you call it the same?
How many carts must our spork show to you,
before you grasp his intent?
Yes and how many times must the props spin around,
before they're understood?

The answer my friend is blowing with the wind,
the answer is blowing with the wind.

How many years will the humber refuse,
before he gets a clue?
How many years must this thread here go on,
before his mind is set free?
How many times can the carts spin their wheels,
while he pretends he can't see?

The answer my friend is Blowing with the Wind,
the answer is blowing with the wind.

How many times must a man talk to him,
before he can see the "why"?
how many ears must one humber have,
before he can hear what people say ?
how many tests will it take till he knows,
that too many people had it right?

The answer my friend is blowing with the wind,
the answer is blowing with the wind.
The answer my friend is blowing with the wind,
the answer is blowing with the wind.
(Fading out)

 

[humber]

Humber:


As if we needed anymore evidence that this guy is flat out whack! LOL

He won't tell me the test until I tell you how I plan to perform the test that he hasn't told me about. ROFLAO!!!

You are an absolute master of nonsense humber.

JB

I accept your challenge of a physical test to invalidate your treadmill.

ETA:
Christian,
I am sure that your ode is very good

 

[ThinAirDesigns]

Sorry, double post.

 

[Christian Klippel]

OMG!! This guy is the master of nonsense -- he actually asked me to tell him how I'm going to perform a test when he hasn't told me what the test is. ROFLAO!!!!

Don't forget his just made challenge for a test to invalidate your treadmill (i guess he means the "test on a treadmill")! That's like a challenge for a test to invalidate wind-tunnels as test-beds for airplanes.

I'll go with spork's suggestion. Whatever comes back from humber, it's just more twisting meanings around, deliberate misinterpretation, and so on.

Greetings,

Chris

 

[humber]

Don't forget his just made challenge for a test to invalidate your treadmill (i guess he means the "test on a treadmill")! That's like a challenge for a test to invalidate wind-tunnels as test-beds for airplanes.

I'll go with spork's suggestion. Whatever comes back from humber, it's just more twisting meanings around, deliberate misinterpretation, and so on.

Greetings,

Chris

You do that. I need only define a test that invalidates the treadmill model. How many would you like?

 

[Dan O.]

You're right. Trouble is, troll posts are so hard to resist. No chance for that earlier suggestion of seeing if he could be banned from the thread, is there? This is just insane.

The 'ignore' function is your friend. Click on the trolls name in a post and select "Add to your ignore list". To make the ignore complete, also edit the options in your control panel and set "Hide ignored posts" to yes. Once you have done this, you won't be able to read or respond to the troll without first reversing the steps taken.

Unfortunately, if anyone does respond to the troll you will still see the quoted troll text. Sometimes it is necessary to put the troll feeders on ignore too.

 

[mender]

Humber's test: replace the propeller with a flywheel, set the cart on the treadmill with the treadmill surface running at 10 mph in the normal direction (front to back or right to left as seen in the small cart videos) and hold it in place until the flywheel gets up to speed, release the cart, run the test for at least one minute and record the result. Next, tilt the front of the treadmill up by 4.4 degrees and repeat the test. Finally, tilt the rear of the treadmill up 4.4 degrees and repeat the test.

If Humber is correct, the cart will remain in a balanced state on the treadmill belt in all three tests. If he's wrong, the cart will not be able to maintain a steady speed on the treadmill and will move off the treadmill belt to the front or the rear.

Perhaps a direct side by side test of the prop cart vs the humber (silent "b"?) cart would reduce any perceived or actual variances.

Maybe a direct measurement of the forces experienced by the two carts would help show any differences. A digital scale, some string, some pulleys and two weights could be used to show both fore and aft forces. Tie a string to the front of the cart, mount a pulley on the front of the treadmill and run the string over the pulley so that the end of the string is hanging, tie that end to the weight (500 grams or so) and set the weight on the scale. Do the same at the other end with half the weight but allow the second weight to hang free. Zero the digital scale. Any change in force will be seen on the scale as a change in weight.

Just a suggestion.

Or instead of one test, agree to one test each, in two stages. First stage, as specified, second stage with "corrections" as seen by the other side.

Can't see that working out well but I thought I'd toss it in.

 

[Dan O.]

Please point to the line where I say the cart has a "variable speed transmission". Unless accounted for, stored energy violates the requirement for steady state performance.

There are no physical differences between 'your' cart and mine. Same 1:1 ratio, same wheels, same propellor, same chassis, right down to the last nut and bolt of the published parts list. I have not seen Goodman's plans, but it looks to me like a bigger version if your cart.

Stop trying to welch out. You agreed to prove me wrong. You failed. Pay up.

 

[Brian-M]

I think there is only one result that would take him down... and that is none of us responding to his trolling (and therefore ruining) of this thread.

Give credit where credit is due. If it wasn't for Humber, this thread would have died the dignified and triumphant death of universal accord and agreement long ago.

 

[Brian-M]

Yes, the cart will move at twice the speed. I have said that before, and again in the last post on that topic. We are definitely in agreement that the cart will move at twice the speed of the overhead belt.

So... You agree that it a cart can travel faster than the medium pushing it?
The DDWFTTW cart claims to to travel faster than the medium pushing it.

Can you see the connection here?

The animated cart is the DDWFTTW cart. It's just using a backwards-rotating wheel to represent a backwards-thrusting propeller and an overhead conveyer belt to represent the wind.

Why do you believe a the wheel-driven cart can work, but a propeller-driven cart can't even work in theory? The physics is the same.

 

[humber]

Stop trying to welch out. You agreed to prove me wrong. You failed. Pay up.

No, I have denied your claim. You must show where I claimed that a variable transmission is required for the momentum model to work.

Do that or withdraw the remark.

 

[humber]

So... You agree that it a cart can travel faster than the medium pushing it?
The DDWFTTW cart claims to to travel faster than the medium pushing it.

Can you see the connection here?

The animated cart is the DDWFTTW cart. It's just using a backwards-rotating wheel to represent a backwards-thrusting propeller and an overhead conveyer belt to represent the wind.

Why do you believe a the wheel-driven cart can work, but a propeller-driven cart can't even work in theory? The physics is the same.

Well, uuum, thanks, Brain_M.

Yes, I do see the connection, and always did, but I do not think that it will directly help the cart.
You are correct when you say Work = fxd, but Power = WorkxTime.
Your cart will need the same amount of power to get it to 2V as a 1/1 cart. However, the force is halved and the 'velocity' doubled, so it will take 4 times as long to get there. What takes 1s, for a 1/1 cart, will take 4s for a -1/2cart. So they are the same, I am afraid. Overall efficiency is likely to be lower than a 1/1.

There is an additional problem that I mentioned earlier on. How do you keep the cart's velocity constant? An incremental change of the conveyer will always produce twice that at the cart. In practice, friction will determine the terminal velocity of the cart, and so that of the conveyer.

Anyway, it appears that the only simple option is to let the cart run a little faster than wanted, and then let it coast a little below that, and then repeat. The average will be the desired speed. How do you do that? Apply a force, stop, and repeat.
This is why I remarked about the fingers of the operator in the video of the skateboard device. That is what he is doing.

Your device would end up being driven for quite a while on the momentum of the rotating mass of the wheels (which also reduce the acceleration). Just like Goodman's cart, though it is the wind, the propeller and the wheels, that determine when to store, and when it is better to trade for velocity.

 

[Michael C]

I've been following the antics of the arrogant Greg London. This is the guy whose first comment on the DDWFTTW cart (on boingboing) was "good grief". His second comment was "So, after finally reverse engineering this thing down to the bones, I wrote up a spec that describes how this bloody thing actually works, and how to build a device that will go directly downwind faster than the wind without any moving parts. Now that I've written it up, I don't know why there is any controversy around this other than no one understood it well enough to explain it in plain english."

He linked to a document which explained how the builders of the DDWFTTW cart didn't have a clue as to what they were doing, and showed his design for a fixed-vane rolling wheel. Which doesn't work. JB explained exactly why it couldn't go faster than the wind .

Now Greg has modified his original document (no fear, I have a copy of the first one). He's realised that the original design doesn't work, so he's included a diagram that reproduces the essential points of JB's diagram, but without giving any credit to JB.

Since he now knows his original design doesn't work, he's proposed a couple of alternatives. The first one is rather similar to Dan O's creation, while the second one looks very like Myriad's chute cart.

I note that in the new document, Greg has removed the phrase "Trying to get the builders to explain how said machines actually work resulted in an amazing amount of unobtainium, handwavium, and complicated invented phrases that don't mean anything." He now says: "No one had any plans. No one could point to one document that could explain from start to finish how this thing work.ed."

huh?

 

[Dan O.]

No, I have denied your claim. You must show where I claimed that a variable transmission is required for the momentum model to work.

Do that or withdraw the remark.

There is nothing to withdraw.

I claim that the wind powered cart can travel faster than the wind pushing it.

It is your burden to prove me wrong. If I was wrong, it would be a simple mater of showing the math for an ideal cart traveling at the speed of the wind to prove that the cart could not accelerate any further. But the math has already been presented and it shows I am not wrong. And several physical models have been independently built and tested which confirm that the math is correct.

The evidence was all posted before I made my challenge but you could not see it then. I thought perhaps if I engaged you in a direct challenge you would settle down and see reality. I couldn't have been further off the mark. You continue to make up your own reality. You can't do the math. You can't even keep your vectors pointing in the right direction.

I'm wishing now that I hadn't proposed the challenge. I don't want you to make a donation to JREF because that would give you the feeling that you belong on a skeptics forum.

I quickly get tired of talking to those that behave like trolls so I'm going to take my own advice and put you back on ignore. If you do somehow manage to convince JREF that the cart cannot work, I'll reexamine your reality.