Hobby Humanoid Robot KHR3HV Rides Bike At 10k/h 114
An anonymous reader points out a fun robot project from Japan, writing: "The robot pedals with its feet at variable speed. The steering is done by the robot hands as with a normal bike, and remote controlled by a human. Stability is achieved by relying on the inertial centrifugal effect of the front wheel and on a gyro aided by a PID controller that takes over steering when driving in a straight line. Seems like when the robot steers his arms he also bends the waist leaning a bit into the turn. Braking is achieved by taking the feet off the pedals and pointing them down to the ground using the metal feet as friction breaks."
annnnnnnnnd.... (Score:1)
slashdotted
Blegh (Score:1)
Slashdotted (Score:4, Informative)
http://robosavvy.com.nyud.net/forum/viewtopic.php?p=32542 [nyud.net]
URL for video (Score:5, Informative)
http://www.youtube.com/watch?v=SqBw7XapJKk [youtube.com]
Re: (Score:1)
At every close up in the video I expected to see a UPS Truck going full speed mow over the little robot man,
Re: (Score:2)
I WANT ONE! It's so cute, it looks like a four-year-old who just learned how to ride a bike!
only 6.2 miles /H (Score:2)
only 6.2 miles /H
Re: (Score:2)
only 6.2 miles /H
But he appears to be only around 1 foot/30cm high, so he's around 1/5 the size of a human rider, he'd ride much faster if he was full size.
Re: (Score:3, Funny)
a robot rode a bike without falling over...... and you're upset he didn't go faster?
Re: (Score:2)
A data rate of just 10000 bits per hour = 3 bit/s (Score:2, Insightful)
I, for one, welcome it that the article tried to mention metric units. But c'mon. 10k/h? That means 10 kilograms per hour or what?
Re: (Score:1)
I, for one, welcome it that the article tried to mention metric units. But c'mon. 10k/h? That means 10 kilograms per hour or watt?
There, fixed that for you.
Re: (Score:3)
It means 10000/h.
Stability is NOT achieved that way. (Score:5, Interesting)
Re: (Score:2)
What about the stability of a motorcycle? As this is often quoted quite a lot with those, and could be more accurate, since the weight of our wheels is a lot more, and they're spinning a lot faster.
For instance, people suggest that when you lift your front wheel, you need to make sure you don't press the front brake, because if it stops spinning, you lose a lot of your stability.
Re: (Score:2)
If you are lifting your front wheel then you are doing it wrong. Both wheels are supposed to be on the ground at all times. If my friend had followed this simple rule, he'd still be around today instead of having gone under a bus.
Re: (Score:3)
Pretty sure motorcycles don't work unless at least 1 wheel (often the front wheel) is off the ground.
Re: (Score:2)
neither :) he implies that the "only proper" way to enjoy a bike is up on one :)
Re:Stability is NOT achieved that way. (Score:5, Informative)
Gyroscopic steering is said to assist no hands bicycle riding, but I'm not a motorcycle rider and don't know about wheelie stability.
Re: (Score:3)
BMX will lock the wheels when performing tricks (in mid air) - it makes the bike a lot less sluggish to manoeuvre. Mountain bike freeriders/dh'ers will leave the wheels running (usually subconsciously) to help keep the bike pointing in roughly the right direction. [try doing a long fast jump with the wheels locked and it definitely loosens everything up - usually ending in a big crash!] -- can't find any internet citations - except that I do it myself.
Re: (Score:1)
Changing wheel speed gives you rotation in the air Sir Newton!
Re: (Score:2)
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.
Re: (Score:2)
Re: (Score:2)
Unfortunately, you are misinterpreting the conclusion of the very interesting article you cited. The
Re: (Score:2)
"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. [wikipedia.org] 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.
Re: (Score:2)
Trail is a guideline used by bicycle designers. It is neither nec
Re: (Score:2)
Re: (Score:2)
On the contrary, the Science paper mentions that negative trail can have a dramatic effect on bicycle stability: "When Jones modified his bicycle by placing the front-wheel ground contact in front of the steer axis (negative trail, c < 0) he could not ride no-hands." Have you read the paper?
One of the most surprising results is that it is possible to construct an unusually weighted "bicycle" that remains stable despite having slightly negative trail. However, this has little relevance to t
Re: (Score:2)
It is not I who is having trouble here. You are confusing whether trail does have an effect on a standard bicycle, with whether it is necessary for the stability of a bicycle.
I apologize if my unfortunate choice of words (e.g., "not an important factor") misled from the point I was trying to make: that according to the Cornell study it is neither the most important factor, or even necessary.
Re: (Score:2)
Here's A. L. Schw
Re: (Score:2)
"You are still incorrect. For the familiar bicycles we ride every day..."
Ehhhhhhhh. (sound of buzzer going off). You lose. You simply proved the point I made in my last comment:
Repeat: "You are confusing whether trail does have an effect on a standard bicycle, with whether it is necessary for the stability of a bicycle." [emphasis added]
Re: (Score:2)
Re: (Score:1)
I certainly don't.
I know that I'm right in that regard, as I've won many a bet, even against physicists, by making that very claim, and then demonstrating it! It seems to be even more how-does-it-work than even fucking magnets [ICP 2009].
I shall definitely enjoy reading that paper - thanks for posting the link!
Re: (Score:3)
OK, so how do you get your center of mass to be positioned to the right? Most riders do so by countersteering - turning slightly left first. Most riders are not conscious of
Re: (Score:1)
Re: (Score:1)
I remember reading about The Wheelie King about 25 years ago and this dude could ride wheelies literally forever, but he had to have an electric motor on the front wheel to keep it spinning for balance. You would think if anyone could ride successfully without the front wheel spinning, The Wheelie King could.
Re:Stability is NOT achieved that way. (Score:4, Informative)
We do understand how to maintain balance on a bike.
People steer into the continual tiny falls that happen all the time, actively steering the bike upright.
Re: (Score:2)
"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.
Re: (Score:2)
It is by the design of the steering mechanism that allows a bike to maintain balance even without a rider. A simple test: Stand beside your bike and with the front wheel straight, lean the bike to the left, the front wheel will turn to the left. Now repeat but lean the bike to the right, the front wheel will turn to the right. It is this that reaction that allows the bike to maintain balance when moving because when the bike begins to lean to either the right or left, the bike will automatically steer to th
Re: (Score:2)
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.
Re: (Score:2)
Well, if a Cornell researcher says it, then it must be true. 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. A simple test of my theory would be to change the steering mechanism of the bike to invert the direction of the wheel when the bike leans - if it is not the steering, then the balance of the bike would be unchanged.
Re: (Score:2)
"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.
Re: (Score:3)
Re:Stability is NOT achieved that way. (Score:4, Interesting)
Actually, no, it's still not the gyroscopic effect keeping you upright. 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.
At low speeds this effect is not enough for stability: with no active control it wants to turn constantly, and follows a squiggly, unsettled path. At mid-speeds it will want to turn, but they will be stable turns. At high speeds the bike becomes over-stable: if you let go mid-turn, the bike will automatically straighten itself out and return to a stable straight line. This is contrary to what you'd expect from the gyro effect, which would be to hold the bike leaning into the turn.
The gyro effect does exist, but its really not that strong compared to your weight and all the other forces involved.
Re: (Score:2)
to prove the parent posters assertion - just try riding a bike with a negative rake.
Re: (Score:2)
"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.
Re: (Score:2)
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.
Re: (Score:2)
"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. [wikipedia.org]
Re: (Score:2)
Re: (Score:2)
"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.
Re: (Score:2)
Either way, according to the Cornell study it is not a major source of stability in a bicycle.
Re: (Score:2)
Did it hurt much?
Re: (Score:2)
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."
Re: (Score:1)
"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 "cent
Re: (Score:1)
Your final sentence is certainly true, though.
Re: (Score:2)
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.
Re: (Score:1)
Search in page for 'trail'
Nothing.
OK, that's only one experiment, but I don't think it's too much to conclude that no matter how many times I read it, I will still not see the word.
Re: (Score:2)
Re: (Score:1)
Re: (Score:2)
10 k/h? (Score:1)
Re: (Score:1)
Re: (Score:2)
Wow, that's almost as weird a claim for what kilo means as 1024.
Catchy name! (Score:2)
Is that inspired by some anime - or hentai - that I've never heard about?
Raleigh Terminator (Score:1)
Sarah Connor? *ding ding-aling* Come with me if you want a backy.
Speed not a problem (Score:3)
Re: (Score:2)
Unfortunately most Japanese tend to ride their bikes at about 10km/h, so speed won't be an issue for this robot.....
Given that they tend to ride on crowded sidewalks, riding slowly is a good thing.
Re: (Score:1)
Re: (Score:2)
Japan != Tokyo.
busy sidewalks != Tokyo
Re: (Score:1)
Re: (Score:2)
Why would they need to be to make that statement?
I've never been to Tokyo, yet I have been on a busy sidewalk, so clearly they aren't unique to Tokyo.
Hey editors, watch your homophones (Score:3)
Brakes. A device that stops the motion of a moving part is called a brake.
Re: (Score:2)
Huh, by "as friction breaks", my head adjusted for the misspelling, and I took it to mean "as friction begins to fail" and was none the wiser.
k/h? (Score:2)
Re: (Score:1)
Re: (Score:1)
Uh no, we never use kelvins per henry to represent speed.
Re:k/h? (Score:4, Informative)
Correct Fact: People in metric countries actually talk in km/h.
Re: (Score:2)
Possibly only correct in my country fact: When speaking, people often talk about "K"s rather than kilometres -- e.g. "I cycled 7 Ks to work today". Worse, they often use the same thing for kilometres per hour, e.g. "I was doing 12 Ks over the limit when the speed camera got me."
Re: (Score:2)
Possibly only correct in my country fact: When speaking, people often talk about "K"s rather than kilometres -- e.g. "I cycled 7 Ks to work today"
In my experience, that's true for Kiwis and Australians (and I don't know about other English-speaking metric countries). I've only ever heard 'kilometres' from non-native-English-speaking-Europeans, and had confused looks when I've said 'kay'.
Re: (Score:2)
The article states k (lower case) which is a prefix, not a unit.
you steer by leaning, not turning the handlebars (Score:2, Insightful)
Seems like when the robot steers his arms he also bends the waist leaning a bit into the turn.
You steer a bicycle at almost any sort of speed by leaning, not turning the handlebars. In fact, if you turned the handlebars without leaning or shifting your weight, you and bike would tip over to the outside of the turn.
https://secure.wikimedia.org/wikipedia/en/wiki/Countersteering#Need_to_lean_to_turn
Make sure to have the "outside" pedal down and put weight on that foot, which shifts the Cg of you and bike low
Re:you steer by leaning, not turning the handlebar (Score:5, Informative)
You should read your link more carefully. Leaning is necessary to turn, but it is not what causes you to turn.
Read the next section. If you want to turn right, you briefly turn the handlebars left. That leans you to the right. You then turn the handlebars to the right, and enter a stable right turn. To exit the turn, you turn right a little harder, which brings you vertical again, and then you straighten out.
Re: (Score:3)
Turning the handlebar helps, but it's not necessary. That's why you can ride a bike without hands, as leaning will cause the handlebar to turn by itself.
Re: (Score:2)
Sure, when riding without hands, an initial lean causes the handlebars to turn, due to the angle of the steering pivot, and that's what causes the bike to change direction. Then the lean needs to be adjusted to stop the bike from falling over.
Point is it's the steering that changes the direction of a bike, not the leaning. Even when steering is initiated with a lean, it's doing it via the steering. The leaning is primarily to stop the bike from falling over.
Re: (Score:1)
Should one of the reasons not be the curvature of the tire cross section itself? As you lean to a side, the inner side of the tire has a smaller radius than the outer side. This will cause the vehicle to turn, won't it? Think about high speed race tracks and cars turning at high speed or think about trains and how curves are handled by them.
Re: (Score:2)
Make sure to have the "outside" pedal down and put weight on that foot, which shifts the Cg of you and bike lower.
Not so - shifting your weight does not alter your center of mass. Weighting the outside foot is good practice for aggressive riders whose inside pedal might otherwise strike the ground in a sharp turn.
I don't see what makes bicycling "nerdy", but if that's what you are looking for try a unicycle.
Re: (Score:1)
Re: (Score:2)
Re: (Score:2)
WHen I took my MSF course, the most valuable I learned was that steering is counter intuitive. Well, I take that back - steering is 100% intuitive since my body knows how to do it, even if it doesn't always make sense to my brain.
When doing a panic turn in obstacle avoidance, if you want to move the bike to the left to avoid the obstacle, you push the handlebar on the left side (i.e. you steer to the right). That quickly tips the bike over into a lean toward the left and your bike moves to the left. Even t
Re: (Score:2)
For any slashdotters looking for a somewhat nerdy form of exercise, you can't get much better than cycling, and I highly recommend looking into it! [...] I do strongly recommend you NOT get a hybrid bicycle, however; the upright position is horribly inefficient and NOT comfortable for any more than a few miles because your weight is not split as evenly between your arms and butt as it is on a road bike.
It's much more complicated than that...
If the bicycle is just for exercise, and all you're going to do is ride for the sake of exercise, then a road bike is fine.
But if you want a more practical bicycle -- something to use to get to work, go shopping, etc -- then a road bike is not the best choice -- far from it. You want something you can attach mudguards and a rear rack to, with a riding position that gives you a clear view. Sensible choices are a hybrid or upright/city bike. A hybrid bike is lighter a
Some suggestions (Score:2)
Impressive (Score:2)
This is a complicated mechanical task, especially the self-balancing mechanism. Nice work.
10 k what? (Score:3)
10 k inches? meters? feet? yards?
k means kilo (1000). It's not a distance unit. I guess it's 10 km (1000 meters). Isn't it basic stuff that every nerd learns at school, at the age of 8 or 9 years?
Ok... (Score:2)
Didn't the segway do this do something like this for a while now?
Activity completion (Score:2)
Outstanding job on the arms. I wonder what process was used to develop the routines, trial and error or machine learning. I can't find any additional info on the "Heart to Heart 4" software.
Stability ability (Score:1)
Hobby level is fast progressing (Score:2)