"The theory of gyroscopic precession holds that when a bike leans to the right or to the left, the spinning front wheel forces the bike to turn into the lean, effectively keeping it upright. Further, the caster effect likens the wheels of bicycles to those on shopping carts.
Next time you go to the grocery store, notice how the point of contact for the cartâ(TM)s wheels are just behind the steering axis, which is the same imaginary line that extends downward from the forks of the bike. That makes wheels on casters self-righting: As soon as they start to tip, they turn into the direction of the fall, straightening themselves out again.
To debunk the theory, Papadopoulous and colleagues built a bike that eliminates both effects."
Okay? One of the two things they were specifically debunking was that trail (or caster) is responsible for the stability of a bicycle.
I did not misunderstand it; perhaps you did. Feel free to read it over again.
"Though if you read what I had written, you will see that what I wrote relies heavily on the mas distribution of the bike to work."
I have to disagree; it seems to me that what you wrote pretty much contradicted everything in that article. But I am willing to suppose that I misunderstood it all.
I agree that a test such as you propose might clarify the issue, if it were carried out in a proper manner.
To make the point clearer: the steering axis could be made as close as desired to the contact point, regardless of rake, by changing the steering axis itself and the wheel size. You could even have a negative rake angle, and still make the steering axis arbitrarily close to the contact patch; it makes no difference.
"According to Wikipedia, ther purpose of the rake is to put the ground contact point of the wheel nearer to the steering axis, to reduce the caster effect and make the wheel easier to turn."
Correction: I thought that caster and trail were calculated differently. But I learned that caster and trail are actually two names for the same property.
That was the whole point: those things are what everybody thinks, but they are untrue!
According to the Cornell researchers, it is the mass distribution of the bike -- both empty and with a rider -- that causes the steering effect. Not the steering design, not the caster or trail, and not a gyroscopic or centripetal effect.
"to prove the parent posters assertion - just try riding a bike with a negative rake."
Your forks would cave in the first time you hit a bump. That was the reason designers included rake in the first place; no rake or negative rake cannot take road shocks. It puts all the strain where the forks are attached to the steering post.
"It would be nice if you actually read the article you are linking. They were also talking about gyroscopic and caster effect and not 'inertial' or 'centrifugal effect'. Here is a quote:
'Gyro effects are important contributors to self-steering [and] so are caster effects. It's just that they are not essential.'
That's not a quote from the article *I* linked to. I have no idea where you got that. The words "gyro" (as opposed to "gyroscopic") and "essential" do not even appear in the article.
So maybe YOU should read the article to which I was actually referring? Here's a direct quote, which directly contradicts what you wrote:
"The theory of gyroscopic precession holds that when a bike leans to the right or to the left, the spinning front wheel forces the bike to turn into the lean, effectively keeping it upright. Further, the caster effect likens the wheels of bicycles to those on shopping carts.
Next time you go to the grocery store, notice how the point of contact for the cartâ(TM)s wheels are just behind the steering axis, which is the same imaginary line that extends downward from the forks of the bike. That makes wheels on casters self-righting: As soon as they start to tip, they turn into the direction of the fall, straightening themselves out again.
To debunk the theory, Papadopoulous and colleagues built a bike that eliminates both effects."
Do you know what the word "debunk" means? Further, maybe you should pick up a physics book? While OP's original article did not use precise terminology, the fact is that "inertial" and "centrifugal effect" both refer to gyroscopic effects.
"The caster and trail (parameters of a bike's front suspension geometry) result in the bike having a self-balancing effect: as you lean to the right, it wants to steer right, and the centrifugal force of the turn pushes you left, keeping you from falling over. This works fine with zero-mass wheels that do not have any gyro effect."
Did you even RTFA? According to the Cornell study, trail has no noticeable effect. They eliminated trail and it made no difference.
Also, if you draw a line through the steering axis, you will see that bicycles do have trail, but they do not have caster. In fact the caster is negative on a bicycle; the wheel hub is in front of the steering axis.
"We do understand how to maintain balance on a bike."
That's completely beside the point, and in many situations not even true. If you read the article, they mention why bikes tend to be stable even on their own, with no human rider.
Okay, so it's not negligible. Still, it's not a major factor.
However, according to the researchers at Cornell I originally linked to, "trail" has virtually no effect at all. The idea that it does is apparently a myth. Or in this case, actually negligible.
Note the distinction: bicycles have trail, but not caster. They are similar, but not the same.
"If you respond to the DMCA asserting you have the rights to the work (for whatever reason, including fair use), the host is supposed to put it back up, and let you and the complainant duke it out in court."
Yes, but that is still suppression of speech without due process. Back when this still used to be the United States of America, they had to take you to court FIRST, and prove their case, before removing your work.
"Using a popular misconception intentionally when one knows better only makes sense if you're engaged in training or dialogue with someone who holds the misconception, "
Repeating yourself is not useful; I understood you the first time.
I simply explained the context in which I made my comment. You are speaking of a completely different context.
Within that context, my statement was correct. But I have already conceded that technically, you were correct. So what's the point here?
You didn't "have me". I just figured that since you obviously don't seem to understand this simple concept, I would give one more try at education here. I'm all about education. But I don't know too many people who have that hard a time understanding this concept. For all I know, you're just trolling me.
""With a gold standard, dollars are fixed in value." If you're not using market value, what definition of value were you using here?"
Fixed in value in relation to gold of course. The market value of gold (market value as defined by what amount of gold is necessary to trade for other commodities.) What did you think I meant?
"I don't see how the solidity of the value of gold with regard to other goods aligns with the fact that the price of an ounce of gold is now over 500% what it was 10 years ago,"
See? There you go again. You just can't get it out of your head that something can have a VALUE that is not directly related to its dollar PRICE. That dollars can vary in VALUE in relation to other things... which is why PRICES change.
The value I am referring to here is simply the amount of gold it would take to directly trade for other things.
"Which is what we call the "price" of those respective other things."
ONLY if gold is the standard for money, and you are talking about "price" in dollars. Otherwise, as the price of gold varied, that price would not necessarily have any relationship to the price of wheat, say, because wheat could also vary in price at rates quite different from the rate of change of the price of gold.
"But dollars can't go up and down in value because they are freely convertible to gold, and your thesis is that gold has rock-solid value."
I stated was that it was "rock-solid" in comparison to fiat dollars. I also clearly stated that it can and does change.
But in fact this is where you are wrong, and where you are failing to see the difference between an independent variable and a dependent variable.
If you fix the price of gold, dollars are still your standard. Dollars can and do go up and down in value, sometimes rapidly and relatively unpredictably. If you tie gold to a fixed amount of dollars, then the value of gold would be defined in terms of dollars, and the value of gold would go up and down as the dollar did. There is nothing there to fix the value of dollars, because dollars are your standard... your independent variable. Instead, what you have done is make gold go up and down (in value) in ways that it would never do in a free market.
To put it a different way: if you attach the dollar to the market value (as defined by other goods) of gold, then the dollar can only vary in value at the same rate gold does. Which is usually very slow. If, instead, you try to tie the value of gold to the value of the dollar (which is what you are doing when you fix the price), then gold can vary in value at the same rate as the dollar... which can be very fast indeed. Which, as I stated before, is ridiculous because it completely detaches gold from any kind of realistic free market value. You haven't actually improved anything. Which is the reason nobody does it. You can't have gold be worth the same amount as platinum one week, then only worth its weight in dirt the next week, then who knows what the week after that. Which is a bit of an exaggeration but it's to make the point.
"When the US had a gold standard, the law said, in so many words, 'A dollar is redeemable for X troy ounces of gold.' Is this the sort of legislation you would propose? How does my characterization of a gold standard differ from yours, in terms of the law you'd write?"
That's not the same question, and not what we were discussing. You were saying that a gold standard is the same as setting a fixed price for gold. But you still don't seem to see that one is
No, I wasn't. Unless I misinterpreted his words. And I have good reason to believe I didn't.
"Private industry prior to the late 90's had very little or no interest in sharing information."
One must ask what GP meant by "sharing information". Sharing information amongst businesses? No, because businesses today have no more interest in sharing information with others than they ever did.
That leaves only the interpretation of: "Sharing information internally." Which they DID have an interest in, and as I pointed out, actually did do.
If my interpretation was wrong, fine. But that's what I based my comment on. And it would mean that GP's comment doesn't make much sense, because businesses today are as jealous of their information as they ever were.
Slashdot Mirror
"Unfortunately, you are misinterpreting the conclusion of the very interesting article you cited."
No, I misunderstood nothing. First, as this clearly shows, trail and caster are the same thing. Second, I will quote, yet again, from the article:
"The theory of gyroscopic precession holds that when a bike leans to the right or to the left, the spinning front wheel forces the bike to turn into the lean, effectively keeping it upright. Further, the caster effect likens the wheels of bicycles to those on shopping carts.
Next time you go to the grocery store, notice how the point of contact for the cartâ(TM)s wheels are just behind the steering axis, which is the same imaginary line that extends downward from the forks of the bike. That makes wheels on casters self-righting: As soon as they start to tip, they turn into the direction of the fall, straightening themselves out again.
To debunk the theory, Papadopoulous and colleagues built a bike that eliminates both effects."
Okay? One of the two things they were specifically debunking was that trail (or caster) is responsible for the stability of a bicycle.
I did not misunderstand it; perhaps you did. Feel free to read it over again.
"Though if you read what I had written, you will see that what I wrote relies heavily on the mas distribution of the bike to work."
I have to disagree; it seems to me that what you wrote pretty much contradicted everything in that article. But I am willing to suppose that I misunderstood it all.
I agree that a test such as you propose might clarify the issue, if it were carried out in a proper manner.
To make the point clearer: the steering axis could be made as close as desired to the contact point, regardless of rake, by changing the steering axis itself and the wheel size. You could even have a negative rake angle, and still make the steering axis arbitrarily close to the contact patch; it makes no difference.
"According to Wikipedia, ther purpose of the rake is to put the ground contact point of the wheel nearer to the steering axis, to reduce the caster effect and make the wheel easier to turn."
No it isn't. According to the part about fork offset ("rake"), it is to mediate the effect of road shock.
Apparently HTML doesn't like é
Touché
Correction: I thought that caster and trail were calculated differently. But I learned that caster and trail are actually two names for the same property.
Are you yet another one who didn't RTFA?
That was the whole point: those things are what everybody thinks, but they are untrue!
According to the Cornell researchers, it is the mass distribution of the bike -- both empty and with a rider -- that causes the steering effect. Not the steering design, not the caster or trail, and not a gyroscopic or centripetal effect.
"to prove the parent posters assertion - just try riding a bike with a negative rake."
Your forks would cave in the first time you hit a bump. That was the reason designers included rake in the first place; no rake or negative rake cannot take road shocks. It puts all the strain where the forks are attached to the steering post.
Pardon me. I looked it up, and trail and caster are not different properties; they are in fact the same thing.
Either way, according to the Cornell study it is not a major source of stability in a bicycle.
The article about the Cornell research did not avoid the word "trail". In fact trail was one of the theories they were testing. Try reading it again.
I stand corrected however, on one point. Earlier I wrote that caster and trail were two different things, apparently they are not.
However, I am not aware of any theory that attributes stability to rake, except for its effect on caster or trail.
"It would be nice if you actually read the article you are linking. They were also talking about gyroscopic and caster effect and not 'inertial' or 'centrifugal effect'. Here is a quote: 'Gyro effects are important contributors to self-steering [and] so are caster effects. It's just that they are not essential.'
That's not a quote from the article *I* linked to. I have no idea where you got that. The words "gyro" (as opposed to "gyroscopic") and "essential" do not even appear in the article.
So maybe YOU should read the article to which I was actually referring? Here's a direct quote, which directly contradicts what you wrote:
"The theory of gyroscopic precession holds that when a bike leans to the right or to the left, the spinning front wheel forces the bike to turn into the lean, effectively keeping it upright. Further, the caster effect likens the wheels of bicycles to those on shopping carts.
Next time you go to the grocery store, notice how the point of contact for the cartâ(TM)s wheels are just behind the steering axis, which is the same imaginary line that extends downward from the forks of the bike. That makes wheels on casters self-righting: As soon as they start to tip, they turn into the direction of the fall, straightening themselves out again.
To debunk the theory, Papadopoulous and colleagues built a bike that eliminates both effects."
Do you know what the word "debunk" means? Further, maybe you should pick up a physics book? While OP's original article did not use precise terminology, the fact is that "inertial" and "centrifugal effect" both refer to gyroscopic effects.
"The caster and trail (parameters of a bike's front suspension geometry) result in the bike having a self-balancing effect: as you lean to the right, it wants to steer right, and the centrifugal force of the turn pushes you left, keeping you from falling over. This works fine with zero-mass wheels that do not have any gyro effect."
Did you even RTFA? According to the Cornell study, trail has no noticeable effect. They eliminated trail and it made no difference.
Also, if you draw a line through the steering axis, you will see that bicycles do have trail, but they do not have caster. In fact the caster is negative on a bicycle; the wheel hub is in front of the steering axis.
"We do understand how to maintain balance on a bike."
That's completely beside the point, and in many situations not even true. If you read the article, they mention why bikes tend to be stable even on their own, with no human rider.
Okay, so it's not negligible. Still, it's not a major factor.
However, according to the researchers at Cornell I originally linked to, "trail" has virtually no effect at all. The idea that it does is apparently a myth. Or in this case, actually negligible.
Note the distinction: bicycles have trail, but not caster. They are similar, but not the same.
So the discussion wasn't moot... but now it's up to UMG to sue if they are going to. They would almost certainly lose.
That doesn't make the DMCA process right, though. There still isn't due process.
"If you respond to the DMCA asserting you have the rights to the work (for whatever reason, including fair use), the host is supposed to put it back up, and let you and the complainant duke it out in court."
Yes, but that is still suppression of speech without due process. Back when this still used to be the United States of America, they had to take you to court FIRST, and prove their case, before removing your work.
A number of very thorough studies have been done. Neither "inertia" or "centrifugal effect" from either front wheel or rear contribute anything significant to the stability of a bicycle. The fact is that even today, we do not fully understand the phenomenon. The only thing we are sure of is that it does not work the way most people think it does.
"Using a popular misconception intentionally when one knows better only makes sense if you're engaged in training or dialogue with someone who holds the misconception, "
That's right. This is Slashdot, remember?
No, it's very popular. If you ask most people what the internet is, most likely 90% or more of them will describe WWW and email, and that's about it.
Just as the popular uses of "schizophrenia" and "paranoia" are technically way off the mark, so is the popular use of "internet".
I'm an idiot because I used the popular definition of a term? Even though I knew what the actual difference is?
That's an interesting point of view. Somewhat sociopathic, I would say, but interesting.
Repeating yourself is not useful; I understood you the first time. I simply explained the context in which I made my comment. You are speaking of a completely different context.
Within that context, my statement was correct. But I have already conceded that technically, you were correct. So what's the point here?
""With a gold standard, dollars are fixed in value." If you're not using market value, what definition of value were you using here?"
Fixed in value in relation to gold of course. The market value of gold (market value as defined by what amount of gold is necessary to trade for other commodities.) What did you think I meant?
"I don't see how the solidity of the value of gold with regard to other goods aligns with the fact that the price of an ounce of gold is now over 500% what it was 10 years ago,"
See? There you go again. You just can't get it out of your head that something can have a VALUE that is not directly related to its dollar PRICE. That dollars can vary in VALUE in relation to other things... which is why PRICES change.
The value I am referring to here is simply the amount of gold it would take to directly trade for other things.
"Which is what we call the "price" of those respective other things."
ONLY if gold is the standard for money, and you are talking about "price" in dollars. Otherwise, as the price of gold varied, that price would not necessarily have any relationship to the price of wheat, say, because wheat could also vary in price at rates quite different from the rate of change of the price of gold.
"But dollars can't go up and down in value because they are freely convertible to gold, and your thesis is that gold has rock-solid value."
I stated was that it was "rock-solid" in comparison to fiat dollars. I also clearly stated that it can and does change.
But in fact this is where you are wrong, and where you are failing to see the difference between an independent variable and a dependent variable.
If you fix the price of gold, dollars are still your standard. Dollars can and do go up and down in value, sometimes rapidly and relatively unpredictably. If you tie gold to a fixed amount of dollars, then the value of gold would be defined in terms of dollars, and the value of gold would go up and down as the dollar did. There is nothing there to fix the value of dollars, because dollars are your standard... your independent variable. Instead, what you have done is make gold go up and down (in value) in ways that it would never do in a free market.
To put it a different way: if you attach the dollar to the market value (as defined by other goods) of gold, then the dollar can only vary in value at the same rate gold does. Which is usually very slow. If, instead, you try to tie the value of gold to the value of the dollar (which is what you are doing when you fix the price), then gold can vary in value at the same rate as the dollar... which can be very fast indeed. Which, as I stated before, is ridiculous because it completely detaches gold from any kind of realistic free market value. You haven't actually improved anything. Which is the reason nobody does it. You can't have gold be worth the same amount as platinum one week, then only worth its weight in dirt the next week, then who knows what the week after that. Which is a bit of an exaggeration but it's to make the point.
"When the US had a gold standard, the law said, in so many words, 'A dollar is redeemable for X troy ounces of gold.' Is this the sort of legislation you would propose? How does my characterization of a gold standard differ from yours, in terms of the law you'd write?"
That's not the same question, and not what we were discussing. You were saying that a gold standard is the same as setting a fixed price for gold. But you still don't seem to see that one is
"WWW is just a protocol running on the internet. How exactly does TBL 'invent' the WWW without the internet in the first place?"
Would you care to try reading my comment again? I wrote:
"When most people say "internet", they are referring to the WWW. I used that as the definition only because most other people do."
Is there anything about that you find confusing?
"Private industry prior to the late 90's had very little or no interest in sharing information."
One must ask what GP meant by "sharing information". Sharing information amongst businesses? No, because businesses today have no more interest in sharing information with others than they ever did.
That leaves only the interpretation of: "Sharing information internally." Which they DID have an interest in, and as I pointed out, actually did do.
If my interpretation was wrong, fine. But that's what I based my comment on. And it would mean that GP's comment doesn't make much sense, because businesses today are as jealous of their information as they ever were.