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The motorcycle of the future is so safe riders can cruise without helmet—all of the thrills with none of the danger—according to BMW.
The German automaker unveiled on Tuesday its Motorrad Vision Next 100, a sleek, self-balancing prototype the company released as part of its 100th anniversary celebrations.
The zero-emissions bike has self-balancing wheels designed to stand upright even at a complete stop, stability that the company says will allow riders to forgo riding a helmet.
"Its self-balancing system will help protect the rider at any time," said Edgar Heinrich, the design director of BMW's motorcycle division. "Any late reaction from the driver will trigger and the vehicle will balance out."
"In the future, motorcycle riders will be able to enjoy riding without protective gear."
The TRON light cycle is almost here.
(Score: 3, Insightful) by Nuke on Friday October 14 2016, @01:56PM
Countersteering on a bike is kind of a dicey proposition. You have to be going quite fast for that to work
I makes me wonder what you understand by "countersteering". I have just checked the Wikipedia definition, and it is in line with what I thought it to be. (I am an experienced racing [pedal] cyclist BTW). To turn a corner you first need to turn the front wheel away from the direction of turn to make the bike "fall" inwards, whereupon you steer into the turn to "catch" the fall at just the right angle; you are then cornering. This brief outward turn is so subtle, brief, and by reflex that most riders are probably unaware that they are doing it - and probably deny it (as you are) because it sounds counter-intuitive. There is no reason to think that the physics are any different for a motorbike.
As for "you have got to be going fast", take a look at the photo sequence in Wikipedia. It is being demonstrated on one of those little monkey bikes indoors at obviously a fairly slow speed. Speed, wheel size and gyroscopic effect have nothing to do with it.
(Score: 1) by Francis on Friday October 14 2016, @02:31PM
I understand it quite well as a physics tutor and motorcyclist, I understand the concept better than just about anybody out there not holding a PhD in physics.
It is completely impossible to countersteer at low speeds. I've tried it myself on multiple times and you cannot countersteer at low speeds. I've drawn the diagrams myself and done the math and it's completely impossible to countersteer unless you're going fast enough. This is something that's taught by the MSF when they teach people to ride, you cannot execute a low speed u-turn by countersteering, it's completely impossible. It's possible to do a high speed u-turn with countersteering, but it's incredibly difficult.
The whole idea of people unconsciously countersteering a bicycle in order to reconcile this just smacks of lazy science at best or pseudo-science at worst. In most of those cases, they're not countersteering at all, they're shifting their body weight to lean the bike. That's what I'd do as bikes don't move fast enough to require countersteering and they haven't got enough gyroscopic precession to force the issue. Assuming they're even leaning it to a noticeable extent. Not to mention that if you were to try it, you'd fall over as there'd be insufficient gyroscopic precession to keep the bike up.
Also, you don't have to lean a bike in order to turn, I'm not sure where that myth came from, but it's demonstrably false. You do have to be going rather slowly in order to do it, but, as long as you have sufficient friction on the tire to take you around the turn, there's no need to lean the bike at all. Take a bike, turn the wheel to the side and counterlean you'll find that at low rates of speed the bike will turn even though there's no lean at all to the bike.
When all is said and done, I wish people would stop spreading these myths about how two wheeled vehicles turn. It's rather tiresome arguing with people that clearly have no idea what they're talking about quoting other people who have no idea what they're talking about when the correct information has been known for decades, if not longer. Most of this stuff has probably been known for at least 80 years.
(Score: 3, Insightful) by Nuke on Friday October 14 2016, @07:43PM
I understand it quite well as a physics tutor .....
In that case you will understand that when cornering the force vector which is the resultant of the gravitational and centrifugal forces must follow a line between the centre of gravity and the tyre contact patch (as viewed in a vertical cross section). This line will be inclined : for example at a speed of 10 m/s on a curve radius of 20 m the centipetal acceleration is :
10*10/20 = 5 m/s/s (about half g)
So the angle of lean will be :
ArcTan (5/9.807) = 27 degrees (9.807 m/s/s being gravitational acceleration, g)
Of course, the bike itself does not have to lean - the rider could lean out from his bike (pointlessly) as long as the centre of gravity of the two is "leaning".
you don't have to lean a bike in order to turn, I'm not sure where that myth came from, but it's demonstrably false. You do have to be going rather slowly in order to do it
No matter how slowly you ride, as long as there are some figures to put into the above calculation there will need to be some leaning.
It is completely impossible to countersteer at low speeds. I've tried it myself on multiple times and you cannot countersteer at low speeds.
Perhaps we are understanding different things by "countersteer". The guy in the Wikipedia photo sequence is managing what I understand by it.
they're not countersteering at all, they're shifting their body weight to lean the bike.
Maybe motorcyclists shift their body weight, I wouldn't know. Competent pedal cyclists generally don't. Shifting body weight is the same as leaning the bike as far as the physics is concerned as it is the CG of the rider/bike combination that matters.
As for not needing countersteering, consider a rider going in a straight line, in quasi-steady state. To corner he needs an external lateral force (the centripetal force) on his centre of gravity, but the only possible source of external lateral force is from his tyre patches which are somewhat below the CG. If he promptly steers left (say) the tyre patches will go left but his CG will continue straight on (at first) as there is no lateral component of force on it (yet). With his vertical support force now to the left of his CG (inducing a clockwise force couple about his forward axis *) he will start to rotate clockwise about his forward axis and begin falling over to the right. However, if the initial left steer was fairly slight, he can now start to steer to the right in time to catch the fall by the time he reaches a balance angle (27 degrees, say, if he taking the turn in the example above) and stabilise in that turning configuration. That leaning angle allows a lateral force component at the CG that provides the required centripetal force. The whole action is done without thinking - it is developing the ability to perform this action without thinking that "learning to ride a bike" is all about, it is fundamental to it.
Thus he achieves a right turn by initiating it with a momentary left steer - so momentary in practice that it will be hardly noticable except to instrumentation. It does not matter how slowly he is going, the principle is the same. It is not possible to corner any other way.
It's rather tiresome arguing with people that clearly have no idea what they're talking about
If you ever come to London, avoid the Underground trains. I was the guy who did the calcs to check the margins against derailment :-)
* The gyroscopic forces of steering the front wheel to the left will only add to the clockwise force couple on the bike frame.