CORed
Penultimate Amazing
Well, I guess I can see how somebody who thinks 0/0 = 0 would think that 700 = 70.
-
Security incident: ISF was recently accessed by intruders. Please change your password, and change it anywhere else you used it. Read more
Merged DDWFTTW in a “Real” Wind
- Thread starter ynot
- Start date
- Status
Well, I guess I can see how somebody who thinks 0/0 = 0 would think that 700 = 70.
Christian Klippel
Master Poster
It means "whatever silly fantasy argument that happens to support my completely wrong understanding of reality, and if needed, lying like there is no tomorrow" to humber.
Greetings,
Chris
Jumping Jehosacarts!
From your reasoning, If there are 60N forces acting on the cart in the vertical direction, we should expect to see the following from F=MA:
60N=0.2A
A=300 m/s**2 or approximately 30gs +z direction-1g for earth's gravity acting on the cart in the -z direction or vertically over the belt since there is nothing to prohibit this acceleration other than the weight of the cart.
Since we do not see the carts rocketing off the belts vertically at 29 gs acceleration, I would think you might want to check the credibility of this claim.
If you want to use math to justify physics outcomes, first you must be able to understand what the equations are telling you!
ETA: I went back and look and you stated 80N in the vertical direction for force. This translates to approximately 39 vertical gs for acceleration!
From your reasoning, If there are 60N forces acting on the cart in the vertical direction, we should expect to see the following from F=MA:
60N=0.2A
A=300 m/s**2 or approximately 30gs +z direction-1g for earth's gravity acting on the cart in the -z direction or vertically over the belt since there is nothing to prohibit this acceleration other than the weight of the cart.
Since we do not see the carts rocketing off the belts vertically at 29 gs acceleration, I would think you might want to check the credibility of this claim.
If you want to use math to justify physics outcomes, first you must be able to understand what the equations are telling you!
ETA: I went back and look and you stated 80N in the vertical direction for force. This translates to approximately 39 vertical gs for acceleration!
Last edited:
Subduction Zone
Muse
- Joined
- Dec 23, 2008
- Messages
- 999
Wrong again ppg. All real forces were analyzed and transformed. You want to try to transform imaginary forces. If there is a force that we are not analyzing it is up to you to prove that force exists and how it affects the cart. And your error ridden energy analysis has been shot down many times over. I see that you are still running away from the force analysis challenge.
Given that you still don't understand how to tell if a wheel is slipping or not or even how it rolls, you not understanding how one establishes credibility doesn't really bother me, it's just one more item to add to the humber list.
I also don't mind being in the group of people that you continually try to discredit in a feeble attempt to raise your self-image; the list contains some pretty impressive names! Thanks!
Minor Change!
CORed, I made a minor change to your statement (in bold) to reflect reality:
"It's one of humber's standard tactics: Proof by insult. If he calls the small cart a toy, or the BB a "rolling junkyard", he thinks he doesn't have to account for the fact that both work exactly as claimed."
Humber, seems to believe he is posting to a crowd who doesn't see through this transparent nonsense to obfuscate the issue. I think he doesn't realize that it only serves to invoke everyone's annoyance at such a trite maneuver and diminishes his argument.
WindGrins
CORed, I made a minor change to your statement (in bold) to reflect reality:
"It's one of humber's standard tactics: Proof by insult. If he calls the small cart a toy, or the BB a "rolling junkyard", he thinks he doesn't have to account for the fact that both work exactly as claimed."
Humber, seems to believe he is posting to a crowd who doesn't see through this transparent nonsense to obfuscate the issue. I think he doesn't realize that it only serves to invoke everyone's annoyance at such a trite maneuver and diminishes his argument.
WindGrins
phunk
Illuminator
- Joined
- Aug 10, 2007
- Messages
- 4,127
*SIGH*
Of course I understand that 70 is 10% of 700. That isn't what is disputed here. What is disputed is that this is the magnitude of the force exerted by a runner.
That 10% figure is not the force of a person running on the treadmill. It is the lateral component of the force, 90 degrees from the direction of the belt's motion. The vertical force of the runner on the belt is about 25 times that. So the noise may match that of a runner in the least important direction, which they admit in the pdf isn't important:
But the noise is much lower than the runner in the directions they (and we) care about.
And the vibration was mostly caused by a custom part that isn't standard on most treadmills... why are we even discussing this?
And that 60N of noise isn't measured at the belt, it's the noise in the force the treadmill exerts on the sensor below it. The noise in the belt's overall (non-rotational) velocity will be much lower. That force will be 60N * mbelt / mtreadmill. See if you can figure out why. Not that it's relevant to a tiny cart that clearly isn't experiencing anywhere near that amount of force.
CORed
Penultimate Amazing
The whole idea that the forces exerted on a treadmill my a person running on it have any relevance whatsoever to the working of a tiny little cart on a treadmill is absurd anyway. This is just more of the denier tactic of introducing something completely irrelevant (e.g, wind shifts before or after the NALSA record trials) and claiming it somehow refutes the claim of ddwfttw.
Let's go cherry picking!
http://jap.physiology.org/content/85/2/764.full.pdf
I find it amusing that in the same paper you took this from, the following was the discussion:
Discussion
From a purely mechanical perspective, steady-speed
walking or running on an adequate motorized treadmill
is identical to overground walking and running; the
only difference is the frame of reference for each
situation (23). Locomotion on a treadmill with inadequate power or momentum (i.e., no flywheel) does
indeed differ from overground locomotion. However, on
a treadmill with an adequate motor and flywheel,
where the belt speed does not vary, the kinematics (21),
ground-reaction forces (19), and metabolic cost (2) of
locomotion are nearly indistinguishable from overground locomotion. As detailed above, our motor and
flywheel appear to be adequate in maintaining a constant tread speed.
So here you are using a paper which says that the transform is "nearly indistinguishable" from overground locomotion to attempt to bolster your point! This is hysterical. No wonder you didn't want us to read the entire paper:
The author was indeed saying that the treadmill had vibration above 46 Hz of very low magnitude. The relevance to our situation is that if the Fz vibrations were enough to cause our carts to lose traction with the belt, we would have wheel slip.
Video #6 and the smoothness of the aliased pinwheels clearly indicate the cart is not losing any traction at WS due to wheel slip.
The TM upper belt surface has always been alive and well!
WindGrins
http://jap.physiology.org/content/85/2/764.full.pdf
I find it amusing that in the same paper you took this from, the following was the discussion:
Discussion
From a purely mechanical perspective, steady-speed
walking or running on an adequate motorized treadmill
is identical to overground walking and running; the
only difference is the frame of reference for each
situation (23). Locomotion on a treadmill with inadequate power or momentum (i.e., no flywheel) does
indeed differ from overground locomotion. However, on
a treadmill with an adequate motor and flywheel,
where the belt speed does not vary, the kinematics (21),
ground-reaction forces (19), and metabolic cost (2) of
locomotion are nearly indistinguishable from overground locomotion. As detailed above, our motor and
flywheel appear to be adequate in maintaining a constant tread speed.
So here you are using a paper which says that the transform is "nearly indistinguishable" from overground locomotion to attempt to bolster your point! This is hysterical. No wonder you didn't want us to read the entire paper:
The author was indeed saying that the treadmill had vibration above 46 Hz of very low magnitude. The relevance to our situation is that if the Fz vibrations were enough to cause our carts to lose traction with the belt, we would have wheel slip.
Video #6 and the smoothness of the aliased pinwheels clearly indicate the cart is not losing any traction at WS due to wheel slip.
The TM upper belt surface has always been alive and well!
WindGrins
Last edited:
Cool. hadn't seen it. I see one wheel is enough. Thanks for linky.
Carteers and deniers is starting to remind me of gangs.
The deniers need new blood.
Its not a fair fight.
Amazing that it goes on and on.
Though it is good nerd fun.
Last edited:
It's not a models of a cart in the wind. The mechanics that keeps that toy on the belt, are completely different. The only connection is the rather boyish idea, that the road goes "backwards" when viewed from a moving vehicle.
And Humber once again posts proof of the fact he doesn't have a clue about what a FOR is, never mind understand the concept.
Your zeal is showing. The thrust remains the same, but the drag force falls with increased speed. That is in complete contradiction to the calculations of the real cart you have posted here.
The TM is yet another bogus claim, exposed by actually examining it, rather that accepting it on the basis of the flattery of "getting it" or told of being a "bright guy".
Need I remind you of the intellectual capacities of the person offering that last epithet, and how easily he may be fooled?
He has never read, let alone understood, Bauer's or Drela's papers.
It is a very naive error to assume that the calculation of net force implies motion. The TM is the result of an error made 60 years ago, that has been repeated by subsequent ddw enthusiasts, because its a canned "proof" they can easily peddle. A gimmick adopted to cover failure of all the carts and its various "theories".
According to Dr Drela each of these carts, consuming 1.8W, will be capable of the same performance in the wind.
I doubt that. Prop power = 1.8W
Belt = 5m/s
Net = 1N - 0.36N = 0.64N
(Power demand 5m/s*1N = 5W)
Belt = 10m/s
Net = 1N - 0.18N = 0.82N
(Power demand 10m/s*1N = 10W)
Belt = 20m/s
Net = 1N - 0.09N = 0.91N
(Power demand 20m/s*1N = 20W)
Belt = 100m/s
Net = 1N -.018N = .982N.
(Power demand = 100m/s*1N = 100W)
The TM has nothing to do with a cart in the wind.
Last edited:
Mender's gauntlet is made of lace.
And you would starve if your dinner was reliant upon your skill.
Last edited:
[/QUOTE]
You really don't understand anything. Each of those carts is responding to the difference between their ground speed and their airspeed, in exactly the same way the real cart does. The bigger the difference, the better they, and it, performs.
Again, as long as their ground speed is greater than their airspeed.
The "airspeed" is zero in all cases. The 1.8W is the power required to spin the prop to produce that static thrust and power, which would be the same if it were a small desk fan. In that case, the motor driving that fan, would turn at the same AV as the fan's shaft.
The belt and wheel are a like gears, that allow a faster motor to run the fan at the same AV, but called a "road".
You have posted calculations that show all drag forces rising with cart velocity. In the case of the TM, the net force "increases" because those opposing drag forces fall.
The TM is nothing like a cart in the wind. It is a gimmick that fooled Spork, and he passed it on to you ( though did his best to claim the idea as his).
To accept the TM as proof of ddw travel, you first need to contradict yourself, so that you can fool yourself. That is a common thread in all of Spork's videos and proofs.
The small cart in the wind is a palpable failure, even as they knowingly watch it contradict each and every claim. The Harold Bricer test shows the cart being repeatedly blown off the belt.
If you take note, you can see JB anticipating that, as he picks it up again before it does.
Same with the BB. Contradiction abound in the dyno test, and in the NALSA trial.
That same person has the hubris and myopically self-focused vision to produce this:
http://www.youtube.com/watch?v=axoflkkwwyI
And if you want to see the consequences of your own math, calculate how much power it takes JB to push the cart to WS, ( or 1mph above it) and then do it using the prop.
Last edited:
You have no idea what my math shows in an apples to apples comparison.
With a windspeed and cart speed of 12 MPH, I get a best net force of 18 N
With a windspeed and cart speed of 15 MPH, I get a best net force of 50 N
With a windspeed and cart speed of 20 MPH, I get a best net force of 119 N
With a windspeed and cart speed of 25 MPH, I get a best net force of 207 N
Once again, reality is at odds with the humberverse.
With a windspeed and cart speed of 12 MPH, I get a best net force of 18 N
With a windspeed and cart speed of 15 MPH, I get a best net force of 50 N
With a windspeed and cart speed of 20 MPH, I get a best net force of 119 N
With a windspeed and cart speed of 25 MPH, I get a best net force of 207 N
Once again, reality is at odds with the humberverse.
ThinAirDesigns
Graduate Poster
- Joined
- Nov 10, 2008
- Messages
- 1,058
I did not ask you for net force. If you like I can show you how to increase net force bt reducing efficiency, but I asked
"And if you want to see the consequences of your own math, calculate how much power it takes JB to push the cart to WS, ( or 1mph above it) and then do it using the prop. "
Mypoia. It's the TM that is the failure. That roller will not exceed WS, but it will travel forwards, and not go backward, nor always twist and fall of the road.
And by the way, the ratchet was not operational during the trial as you claimed.
Last edited:
- Status