Hobby Humanoid Robot KHR3HV Rides Bike At 10k/h

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Hobby Humanoid Robot KHR3HV Rides Bike At 10k/h

Posted by timothy on Saturday October 22, 2011 @02:46PM from the not-even-training-wheels dept.

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."

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annnnnnnnnd.... by Anonymous Coward · 2011-10-22 14:55 · Score: 1

slashdotted
Blegh by Anonymous Coward · 2011-10-22 14:57 · Score: 1

The site was probably written in opa
Slashdotted by definate · 2011-10-22 14:59 · Score: 3, Informative

http://robosavvy.com.nyud.net/forum/viewtopic.php?p=32542

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1. Re:Slashdotted by tsa · 2011-10-23 00:26 · Score: 1
  
  I WANT ONE! It's so cute, it looks like a four-year-old who just learned how to ride a bike!
  
  --
  -- Cheers!
2. Re:Slashdotted by Anonymous Coward · 2011-10-23 15:03 · Score: 0
  
  It's all fun and games now, but in ten years you'll be running down the street yelling "Robot stole mah bike!"
only 6.2 miles /H by Joe_Dragon · 2011-10-22 15:00 · Score: 1

only 6.2 miles /H
1. Re:only 6.2 miles /H by hawguy · 2011-10-22 15:12 · Score: 1
  
  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.
2. Re:only 6.2 miles /H by Anonymous Coward · 2011-10-22 15:33 · Score: 3, Funny
  
  a robot rode a bike without falling over...... and you're upset he didn't go faster?
3. Re:only 6.2 miles /H by derGoldstein · 2011-10-22 21:34 · Score: 1
  
  Depends on whether or not that's the only function it can perform. If the robot can also be removed from the bike and walk, then it's an achievement. It appears that it has all the usual servo-hinges that other biped robots has, so my guess is that it can.
  
  --
  Entomologically speaking, the spider is not a bug, it's a feature.
URL for video by definate · 2011-10-22 15:01 · Score: 4, Informative

http://www.youtube.com/watch?v=SqBw7XapJKk

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1. Re:URL for video by Anonymous Coward · 2011-10-22 16:46 · 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,
Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-22 15:09 · Score: 4, Interesting

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.
1. Re:Stability is NOT achieved that way. by definate · 2011-10-22 15:28 · Score: 1
  
  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.
  
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2. Re:Stability is NOT achieved that way. by Col+Bat+Guano · 2011-10-22 15:39 · Score: 3, 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.
3. Re:Stability is NOT achieved that way. by flyingfsck · 2011-10-22 16:30 · Score: 2
  
  It is true that the gyro effects are not needed to ride a bike. That is why one can ride a bike with tiny wheels just as well as one with big wheels. However, at high speed it does have a very noticeable effect and does contribute to stability - for good or worse if your wheels are badly balanced. Once you reach speeds of 80km or over, the gyro effect becomes very strong indeed - you can literally hang off the side of a bike and not fall immediately, it will just turn slowly - been there.
  
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4. Re:Stability is NOT achieved that way. by vivian · 2011-10-22 16:40 · Score: 1
  
  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.
5. Re:Stability is NOT achieved that way. by definate · 2011-10-22 16:52 · Score: 2
  
  Pretty sure motorcycles don't work unless at least 1 wheel (often the front wheel) is off the ground.
  
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6. Re:Stability is NOT achieved that way. by Anonymous Coward · 2011-10-22 17:05 · Score: 0
  
  Pretty sure motorcycles don't work unless at least 1 wheel (often the front wheel) is off the ground.
  Hmmmm...
7. Re:Stability is NOT achieved that way. by thestuckmud · 2011-10-22 17:40 · Score: 4, Informative
  
  This paper" states that "contrary to common belief, gyroscopic forces play only a limited role in balancing and steering". The "feel" of a bike (pedal or motor) is said to be dominated by "trail", and aspect of steering geometry; gyroscopic torque is "non-negligible", but "much smaller than trail torques".
  
  Gyroscopic steering is said to assist no hands bicycle riding, but I'm not a motorcycle rider and don't know about wheelie stability.
8. Re:Stability is NOT achieved that way. by jklovanc · 2011-10-22 17:47 · 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."
9. Re:Stability is NOT achieved that way. by subreality · 2011-10-22 17:59 · Score: 3, 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.
10. Re:Stability is NOT achieved that way. by Anonymous Coward · 2011-10-22 20:10 · Score: 0
  
  As an anonymous coward, who on the Internet can claim to ride a motorcycle and have read some summaries about bicycle engineering in a book, my opinion agrees that "trail" is where it's mostly at. If you want to test this, just build a bike or motorcycle with negative trail and see how well it rides. (It should still be ridable, or else people wouldn't be able to ride bicycles backward. It just might not be or feel stable, and I couldn't recommend riding it hands-free.)
11. Re:Stability is NOT achieved that way. by gTsiros · 2011-10-22 20:17 · Score: 1
  
  neither :) he implies that the "only proper" way to enjoy a bike is up on one :)
  
  --
  Looking for people to chat about multicopters, coding, music. skype: gtsiros
12. Re:Stability is NOT achieved that way. by rapiddescent · 2011-10-22 20:55 · Score: 2
  
  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.
13. Re:Stability is NOT achieved that way. by rapiddescent · 2011-10-22 20:56 · Score: 1
  
  to prove the parent posters assertion - just try riding a bike with a negative rake.
14. Re:Stability is NOT achieved that way. by tsa · 2011-10-23 00:30 · Score: 1
  
  Did it hurt much?
  
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  -- Cheers!
15. Re:Stability is NOT achieved that way. by fatphil · 2011-10-23 05:14 · Score: 1
  
  If you lift your front wheel and retard it, then you're basically asking to high side if it gets traction when it touches down. I think that risk far outweights any stability issue; you never want to high side, full stop.
  
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  Also FatPhil on SoylentNews, id 863
16. Re:Stability is NOT achieved that way. by fatphil · 2011-10-23 05:23 · Score: 1
  
  The article and paper seem to think that there are only two degrees of freedom for wheel placement geometry, but there are three. Quite why both avoided the words "rake" and "trail" is worrying too. I got the impression that these people really didn't understand the field at all.
  
  Your final sentence is certainly true, though.
  
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  Also FatPhil on SoylentNews, id 863
17. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:14 · Score: 1
  
  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.
18. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:16 · Score: 1
  
  "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.
19. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:19 · Score: 1
  
  "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.
20. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:29 · Score: 0
  
  "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.
21. Re:Stability is NOT achieved that way. by fireman+sam · 2011-10-23 08:35 · Score: 1
  
  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 the same direction causing the bike to turn. This turning causes a centripetal force around the curve. The bike, which has mass, wants to continue in a straight line and causes the bike to rotate over its own wheels, causing it to straighten up (or to maintain balance). The effect is magnified as the bike slows down due to the momentum of the bike diminishing and can be witnessed as the bike begins to wobble before finally falling due to insufficient momentum to carry its center of mass over the fulcrum.
  
  --
  it is only after a long journey that you know the strength of the horse.
22. Re:Stability is NOT achieved that way. by fatphil · 2011-10-23 08:37 · Score: 1
  
  Curious link. Do you honestly expect people to believe this - "Did you know that to turn a bike to the right, you actually push the handlebars to the left?"?!?!?
  
  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!
  
  --
  Also FatPhil on SoylentNews, id 863
23. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:38 · Score: 1
  
  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.
24. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:40 · Score: 1
  
  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.
25. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:42 · Score: 1
  
  "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.
26. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:47 · Score: 1
  
  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.
27. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 08:50 · Score: 1
  
  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.
28. Re:Stability is NOT achieved that way. by fireman+sam · 2011-10-23 09:25 · Score: 1
  
  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.
  
  --
  it is only after a long journey that you know the strength of the horse.
29. Re:Stability is NOT achieved that way. by EETech1 · 2011-10-23 09:32 · 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.
30. Re:Stability is NOT achieved that way. by EETech1 · 2011-10-23 09:34 · Score: 1
  
  Changing wheel speed gives you rotation in the air Sir Newton!
31. Re:Stability is NOT achieved that way. by thestuckmud · 2011-10-23 10:13 · Score: 1
  
  Well... Bicycle frame builders don't talk about caster, which refers to an angle related to head tube angle and possibly rake (I'm not sure which angle it actually refers to). We do talk about rake (the distance the fork is offset from the steering axis) and trail (the distance between the point where the steering axis intersects the ground and the vertical projection of the wheel axis onto the ground).
  
  Unfortunately, you are misinterpreting the conclusion of the very interesting article you cited. The fact that a highly unusual, riderless "bicycle" with bizarre mass distribution happens to be stable does not invalidate the fact that trail forces are the most significant contribution to stability in conventional bicycles. If you don't believe me, read the literature (starting with the article I cited earlier) or ride a bike built with zero or negative trail.
  
  By the way, the authors of the study you mentioned are friendly and eager to discuss their results. They joined the framebuilders forum (now a google group) and contributed to the discussion we were having about the article. Unfortunately, they are not able to relate their result to conventional bicycles. The best insight they are able to offer about it is that the eignevalues for their weird machine indicated stability.
32. Re:Stability is NOT achieved that way. by thestuckmud · 2011-10-23 10:35 · Score: 2
  
  Forget about the handlebars for a moment. The fact is that you can't turn to the right unless your center of mass is to the right of the bicycle's wheels. If you try to turn from a stable position, you will soon find yourself fall to the left and will crash unless you correct your course by turning left. That's the crucial point.
  
  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 this process. There are other ways. You might hop the bike to the left, or tilt the bike and rely on the curvature of the tires. As a somewhat proficient unicyclist, my eyes have been opened to the variety of subtle influences that can influence the behavior of a wheel, so, sure, pushing handlebars is not the only way to turn.
  
  FWIW, I built myself a nice road bike a little while ago with a subtly more stable frame (combination of wheelbase, angles, trail) than is currently in fashion. It is quicker at turning than my old bike because I can apply a lot of countersteering while keeping better control through the middle and exit of a turn.
33. Re:Stability is NOT achieved that way. by fatphil · 2011-10-23 10:40 · Score: 1
  
  The article is http://robosavvy.com/forum/viewtopic.php?p=32542
  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.
  
  --
  Also FatPhil on SoylentNews, id 863
34. Re:Stability is NOT achieved that way. by ultranova · 2011-10-23 11:11 · Score: 1
  
  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.
  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.
  
  --
  Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
35. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 19:10 · Score: 1
  
  "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.
36. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 19:13 · Score: 1
  
  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.
37. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 19:16 · Score: 1
  
  "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.
38. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 19:22 · Score: 1
  
  "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.
39. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-23 19:30 · Score: 1
  
  But you were replying to ME, and the article I linked to specifically covered trail.
40. Re:Stability is NOT achieved that way. by fatphil · 2011-10-23 20:44 · Score: 1
  
  Good point. My attention wasn't on slashdot yesterday (messing about with trying new lightweight browsers) and I misspoke. The article I was refering to, the one that doesn't mention trail, is indeed the one you linked too. So I was right about that. However, I also misspoke in that I should have said "abstract" rather than "paper". So I boobed about that. If the abstract doesn't give me confidence in the reliability of the paper, clearly I'm not going to download the paper.
  
  --
  Also FatPhil on SoylentNews, id 863
41. Re:Stability is NOT achieved that way. by Anonymous Coward · 2011-10-23 22:28 · Score: 0
  
  Are you yet another one who didn't RTFA?
  slashdotted. It's not like some of us didn't try to RTFA.
42. Re:Stability is NOT achieved that way. by thestuckmud · 2011-10-24 04:25 · Score: 1
  
  First, try googling "bicycle castor". You will find that the unfortunate clause in the Wikipedia article you cite is the only reference on the internet that equates caster with trail. The word "caster" when used with regard to vehicle suspensions refers to an angle, not a linear measurement. The confusion probably arose due to the fact that castor angle can be inferred from rake, trail, and wheel size, which are all linear measurements.
  
  Trail is a guideline used by bicycle designers. It is neither necessary nor sufficient for stability: The authors of the Science article (sources and preprint here) built a stable negative-trail "bicycle"; and they show that the eigenvalues for conventional bicycles are unstable above a critical speed. However, the suggestion that trail - the largest force affecting steering - is irrelevant to the stability of conventional bicycles is ludicrous. You can do the math and calculate eigenvalues as you alter trail, or simply ride a bike equipped with an adjustable trail for to see this for yourself.
  
  To quote Jim Papadopoulos, "perhaps the main message is that our reasoning about how trail affects bicycle stability has been quite wrong for 120 years". This is not a denial that trail affects stability, but rather a search for a better model. Unfortunately, that better model has not yet yielded any insights of use to the designers of actual ridden bicycles.
43. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-24 05:32 · Score: 1
  
  But you neglected the part of the study that showed eliminating trail had no significant effect on the stability. While that is not an explicit statement by a researcher, it strongly implies that trail is not, in fact, an important factor.
44. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-24 05:34 · Score: 1
  
  I should add that your comment has also restored my earlier belief that caster and trail are indeed calculated differently.
45. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-24 05:36 · Score: 1
  
  No, apparently you are still somewhat confused. The article that I linked to is about some research done at Cornell, but doesn't include an abstract. And it does discuss trail.
46. Re:Stability is NOT achieved that way. by thestuckmud · 2011-10-24 06:24 · Score: 1
  
  Sigh...
  
  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 the practical sort of bicycles we ride which lack large amounts of mass ahead of the front wheel.
47. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-25 11:01 · Score: 1
  
  Yes, I have the paper, but it is irrelevant to the discussion.
  
  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.
48. Re:Stability is NOT achieved that way. by thestuckmud · 2011-10-25 17:18 · Score: 1
  
  You are still incorrect. For the familiar bicycles we ride every day, trail is the most important factor governing bicycle self-stability. Sure, you can read the supporting text for the Science paper and find a half dozen or more two-mass-skate bicycles with surprising stability properties, and there may be more to discover, but if they do not reflect the properties of the designs we have found to be useful, or suggest new alternatives, then the analysis is of purely academic interest.
  
  Here's A. L. Schwab, one of the authors of the Science paper, explaining that not only does mass distribution have "a strong influence on bicycle stability, but so do gyros and trail". Now, even though the Cornell-Wisconsin-Delft team avoid ranking the importance of these factors, we know, through experiment and analysis, that trail is a very relevant factor influencing the stability of the familiar bicycles we ride every day. You have been consistently discounting this very important factor.
49. Re:Stability is NOT achieved that way. by Jane+Q.+Public · 2011-10-25 19:04 · Score: 1
  
  "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]
10 k/h? by Anonymous Coward · 2011-10-22 15:11 · Score: 1

Kilo what per hectare?
1. Re:10 k/h? by TarMil · 2011-10-22 17:18 · Score: 1
  
  Well tried, but if you're so picky, you should know that hectare is ha (as in "hecto-are").
2. Re:10 k/h? by Anonymous Coward · 2011-10-22 19:31 · Score: 0
  
  The answer is simply 10000/h.
3. Re:10 k/h? by beelsebob · 2011-10-22 20:49 · Score: 1
  
  Wow, that's almost as weird a claim for what kilo means as 1024.
Catchy name! by macraig · 2011-10-22 15:11 · Score: 1

Is that inspired by some anime - or hentai - that I've never heard about?
Raleigh Terminator by RobDollar · 2011-10-22 15:12 · Score: 1

Sarah Connor? *ding ding-aling* Come with me if you want a backy.
Speed not a problem by antifoidulus · 2011-10-22 15:16 · Score: 2

Unfortunately most Japanese tend to ride their bikes at about 10km/h, so speed won't be an issue for this robot.....

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Monstar L
1. Re:Speed not a problem by hawguy · 2011-10-22 15:22 · Score: 1
  
  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.
2. Re:Speed not a problem by antifoidulus · 2011-10-22 15:38 · Score: 0
  
  Japan != Tokyo.
  
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  Monstar L
3. Re:Speed not a problem by hawguy · 2011-10-22 16:59 · Score: 1
  
  Japan != Tokyo.
  busy sidewalks != Tokyo
4. Re:Speed not a problem by antifoidulus · 2011-10-22 17:17 · Score: 0
  
  says someone who has probably never been outside a major city.
  
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  Monstar L
5. Re:Speed not a problem by nedlohs · 2011-10-22 17:58 · Score: 1
  
  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 by voidptr · 2011-10-22 15:47 · Score: 2

Brakes. A device that stops the motion of a moving part is called a brake.

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1. Re:Hey editors, watch your homophones by dmomo · 2011-10-22 20:24 · Score: 1
  
  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? by Sami+Lehtinen · 2011-10-22 16:25 · Score: 2

K/H? I did WT*. Among Techies, this is major fail. https://secure.wikimedia.org/wikipedia/en/wiki/International_System_of_Units
1. Re:k/h? by Rennt · 2011-10-22 18:16 · Score: 0
  
  Fun Fact: People in metric countries actually talk in K/H, not m/s.
2. Re:k/h? by Anonymous Coward · 2011-10-22 18:53 · Score: 1
  
  Uh no, we never use kelvins per henry to represent speed.
3. Re:k/h? by Noughmad · 2011-10-22 19:36 · Score: 3, Informative
  
  Correct Fact: People in metric countries actually talk in km/h.
  
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4. Re:k/h? by Hognoxious · 2011-10-23 06:43 · Score: 1
  
  The article states k (lower case) which is a prefix, not a unit.
  
  --
  Confucius say, "Find worm in apple - bad. Find half a worm - worse."
5. Re:k/h? by don.g · 2011-10-23 11:15 · Score: 1
  
  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."
  
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6. Re:k/h? by xaxa · 2011-10-23 14:41 · Score: 1
  
  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'.
you steer by leaning, not turning the handlebars by SuperBanana · 2011-10-22 17:20 · Score: 1, 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 lower. Want some extra fun? Lean the bike while not leaning your body!
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! There are so many kinds of riding out there, there's something for everyone, even if you have no interest in competition. 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.
Get a road bike from a store that will do a fitting session with you (there's a lot of biomechanics involved- the bars and seat both need to have their height and front-back position set properly), and save money in your budget for accessories clothing (a comfortable pair of bib shorts is essential, and clipless pedals/shoes make pedaling far more comfortable and efficient.)

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Some suggestions by atari2600a · 2011-10-22 17:33 · Score: 2

Make it's face either Hello Kitty or a mecha drill, put it on a scale Honda Super Cub & fit it with a scale Malaysian stereo kit that blasts the J-poppiest happy hardcore you can find. Or YMCK. Then I'm sold.
Police closing in on Occupy Chicago by Anonymous Coward · 2011-10-22 17:37 · Score: 0

History in the making...
Chicago police closing in on Occupy protesters in Chicago. Live feed:
http://www.livestream.com/globalrevolution
Re:you steer by leaning, not turning the handlebar by subreality · 2011-10-22 17:42 · Score: 4, 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:you steer by leaning, not turning the handlebar by thestuckmud · 2011-10-22 18:02 · Score: 1

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.
nitpick by Anonymous Coward · 2011-10-22 18:46 · Score: 0

"10000 per hour"? 10000 what per hour? Sloppy, sloppy.
On a related note: "millions of kilometres" (like you occasionally see mentioned in popular press utterings about spaaaaaaace) would by rights be gigametres, yes.
Re:you steer by leaning, not turning the handlebar by atari2600a · 2011-10-22 19:00 · Score: 1

You guys are way overthinking this. Countersteering only takes effect past a certain velocity, as any motorcyclist will tell you. Yet, while it greatly increases efficiency, you can get by without it through EXTREMELY PRECISE steering or a drastic reduction in speed. I've heard cases of motocross racers being asked 'Why don't you counter steer?' & they go all 'Counter-what?' Leaning, on the other hand, is required to balance any 2-wheeled vehicle. I'll assume that when the robot turns the handlebars, his gyroscopes impede the offset effectively keeping the robot balanced. So while leaning is a big part of accomplishing steering, you STEER with the STEERING WHEEL, or in this case handlebars.
Re:you steer by leaning, not turning the handlebar by Anonymous Coward · 2011-10-22 19:05 · Score: 0

Absolutely correct. I ride a (low) recumbent bicycle where shifting body weight is not possible because of the reclined backrest. It had a 16" front wheel, (20" rear) so the centrifugal effect is also very small. Because of its low COG, this bike can drop in and out of a tight corner very fast, and the only way to actually do that is to steer (quite lot) into the opposite direction, making the bike fall over, and then returning to strait handlebars while making the turn. At the end of the turn, I steer into into the corner to put the bike upright again, making it go into a strait line.
Balancing the bike is also done using the handlebars. (This takes first-time recumbent riders a few minutes to get used to.)
Re:you steer by leaning, not turning the handlebar by Hentes · 2011-10-22 21:05 · Score: 2

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.
Impressive by Hentes · 2011-10-22 21:10 · Score: 1

This is a complicated mechanical task, especially the self-balancing mechanism. Nice work.
I for one by Anonymous Coward · 2011-10-22 21:14 · Score: 0

I for one welcome our new bicycle recreating robot overlords, small in stature but big on soaking up life one bike path at a time.
10 k what? by jb_nizet · 2011-10-22 21:25 · Score: 2

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?
1. Re:10 k what? by Anonymous Coward · 2011-10-23 03:08 · Score: 0
  
  Americans like to bastardize the metric system. They call 5 km "5K", they write kph, they write mb for megabyte. Utilities even write "Kwh" on your bill.
2. Re:10 k what? by Anonymous Coward · 2011-10-24 08:52 · Score: 0
  
  Not in the USA it seams.
A data rate of just 10000 bits per hour = 3 bit/s by Anonymous Coward · 2011-10-22 21:27 · 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?
Aaaw... by Anonymous Coward · 2011-10-22 21:59 · Score: 0

They grow up so fast :'-)
My response: by Anonymous Coward · 2011-10-22 23:27 · Score: 0

Pussy.
Re:A data rate of just 10000 bits per hour = 3 bit by Anonymous Coward · 2011-10-23 00:07 · 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.
Ok... by errandum · 2011-10-23 00:23 · Score: 1

Didn't the segway do this do something like this for a while now?
Re:A data rate of just 10000 bits per hour = 3 bit by tsa · 2011-10-23 00:27 · Score: 2

It means 10000/h.

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Activity completion by sgt+scrub · 2011-10-23 00:43 · Score: 1

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.

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Re:you steer by leaning, not turning the handlebar by Spacejock · 2011-10-23 00:48 · Score: 1

I have a road bike, a flat bar and a hybrid. The hybrid is the most comfortable for long distances, but I added a pair of tri-bars which allows me to lean forward and put the weight on my elbows. I'm used to spending hours in that position, which is probably why it's the most comfortable way to ride.

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Re:you steer by leaning, not turning the handlebar by BasilBrush · 2011-10-23 01:06 · Score: 1

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:you steer by leaning, not turning the handlebar by hawguy · 2011-10-23 01:41 · Score: 1

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 though you steered to the right. Oh, and make sure that your looking at the opening where you want to go and not the obstacle itself or you may steer yourself right into it.
Re:you steer by leaning, not turning the handlebar by ap7 · 2011-10-23 02:51 · 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.
No better than a monkey. by Anonymous Coward · 2011-10-23 03:46 · Score: 0

It is said a circus trainer can teach an ape or even a monkey how to ride a bike, but to replace the chain, never! Ditto for robots for the time being.
BTW, if the japanese are so far into advanced robotics, how come there was none at Fukushima? They had to accept US robots and it humiliated them very much.
Stability ability by wjcofkc · 2011-10-23 04:40 · Score: 1

It almost sounds like the hardware in a phone could be used to keep this thing stable. I wonder if it runs Android.

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Hobby level is fast progressing by savuporo · 2011-10-23 07:26 · Score: 1

This is awesome. Just a few years ago, it took Toyota research to put this little guy together : http://www.youtube.com/watch?v=VDm22U_teoQ And it used active internal gyro wheel to balance itself. Now a pretty much off the shelf stock humanoid does the trick without special aids. It won't be long before these little hobby "toys" will be surpass the current capabilities of best lab robots. Several underlying technology trends are making them more and more capable. Rapidly advancing sensors of all sorts ( accelerometers, gyros, tactile, position feedback ) and massive distributed computing power provided by cheap chips like Cortex-M0 are closing a lot of loops, and even actuators such as shaped memory alloy linear motors are making new strides.

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Re:you steer by leaning, not turning the handlebar by Anonymous Coward · 2011-10-23 08:00 · Score: 0

You should NOT be supporting yourself on your hands on a bike. They should be there for some light support, but it's your legs and butt that should be supporting you.
Re:you steer by leaning, not turning the handlebar by xaxa · 2011-10-23 14:55 · Score: 1

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 and faster, and probably the typical choice for most places in North America, the UK, and other places where cycling isn't especially popular.
At work, out of the 40 or so bikes locked outside my building there are two or three road bikes, with lycra-clad riders -- they extend their journey home for exercise, and get the train if it's raining. There are a couple of folding bikes, a work bike, and a tricycle. There are probably a couple of singlespeeds etc. The majority are a mix of hybrid and city bikes.