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Scientists Build Wireless Bicycle Brakes
itwbennett writes "Computer scientists at a German university have built a set of brakes controlled using a small motor for a braking mechanism and a wireless signaling device to tell it when to brake and how hard. 'Making a popular set of bike brakes wasn't really the point of the project,' says blogger Kevin Fogarty. 'The project was to find out how to make the wireless connections between two components of a system that has to operate in real time – with milliseconds of difference between success and failure (PDF) – more reliable than systems that are normally connected by a wire.'"
I haven't had a head injury in a while, where do I sign up to try them out?
Works GREAT... until the battery dies and you hit a car.
Welcome to OnStar, can I help the police violate your rights today?
I guess I am not understanding the issue here but how is adding touch points reducing the failure rate? Regardless that is fixing a problem that does not really exist.
I know people who ride competitively, reliability is key and introducing more components that can break or add weight is not going to get acceptance. Modulation is key and I really doubt you can simulate that with any wireless system.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
"Brakes". The word you're trying to write is "brakes".
No sig today...
To be useful, this would probably have to include some kind of force-feedback, so you know how hard you're pressing. You can't deduce this from lever position, because the brake pads wear down over their life. So, you'll need a motor in the handle, as well as in the brake itself.
On the up-side, it will mean you can incorporate front brakes on those BMX stunt bikes where some of the tricks involve spinning the handlebars all the way around.
Also also: "brake" == device for slowing something down, or the process or effect of slowing something down; "break" == to damage or destroy something, the act of destroying something, or a gap or discontinuity. FYI.
2*3*3*3*3*11*251
Don't you just peddle backwards?
Wireless systems... needing power and chips and antennas and receivers and complicated communication protocols... more reliable than steel wire... Hmmm... Best of luck with that!
I don't respond to AC's.
This isn't about wireless bike brakes, it's about reliable, real-time wireless connections. Surely that's something nerds can find a use for?
1 in a trillion. Yeah right. What happens when someone signal jams my brakes, or you are driving past an electric fence, near lightning or some other failure. I will let others be the guinea pigs.
OnStar has to be the scariest add-on for a car I can think of. There's no fucking way I'd let some device controlled by a remote person control the engine/braking of my car.
The day brain implants that can override your own muscle controls, designed for paraplegics etc., becomes a standard offering from hospitals will be the day someone in government has the thought "can we install these in ciminals?"
Slippery slope...
Why don't they go full Java Enterprisey Enterprise Edition Library - Government Edition, and make a hamster-fart-powered brake factory factory-making Rube-Goldberg machine factory production contractor factory... factory?
Then at least it wouldn't be trivial. :P
Someone needs to give one of these bikes to the Jackass guys - with a 2nd remote control.
To do something right, you often have to roll up your sleeves and get busy.
Granted I'm still pro wire vs wireless, that could have multiple variables make it go wrong, like a microwave or something. The only downside to a physical cable is that after prolonged use, eventually the cable will stretch. By this time, an aware rider would notice and either replace the cable or have it replaced. If it's not terribly broke, don't fix it.
I don't think the cables stretch so much as the housing compresses. But in any case, it's a gradual process, and the rider only needs to twist the cable adjusting barrel that most bikes have a few turns to make up for it.
...Will make brakes that stop working for like, no reason?
Sorry, but TFA is hard pressed to convince me a wireless connection will be more reliable than a wire (even with consideration of the mechanical connections). I'd not want to be in a airplane that used fly-by-wireless instead of fly-by-wire.
My karma is not a Chameleon.
No, Engineers built them. Doesn't matter what profession these guys have or what investigations into the universe they do while on the clock. This development is outside the realm of question, therefore it's not science, it's engineering.
I swear they give me mod points to shut me up.
The summary says with milliseconds of difference between success and failure, but the article and paper says it has to react within 250 milliseconds - that's 1/4 of a second. My cable brakes react much quicker than that.
Calling that mere "milliseconds of difference" is like saying something that costs $2.50 costs only "pennies".
...someone figures out how to send a brake command to other people's bikes from a laptop? Even better yet, just send the brake command to people's front brakes... flipping them over when they least expect it! I imagine sitting by the window in a coffee shop while all the bikers who attempt to ride by are in for quite a surprise.
I like my brakes reliable. I know as a BMXer when the current trend is to go brakless I sound like a heretic. I'm old. I'm an old-school BMXer, I think the trend is stupider than these brakes, but at least someone who follows the trend knows they're riding without brakes unlike the people with these wireless ones.
I would be worried about other problems. When I ride my dork bike I have a pair of Cy-Fi Bluetooth speakers on my handlebars blaring AC/DC and Beastie Boys at people I pass. Every time I stop at a stoplight something happens. My music get interrupted. I'm not sure exactly what goes on with stoplights, but there's very definitely something going on wirelessly that interferes with my Bluetooth speakers. When I got caught at the train tracks the speakers were out for more than just the little blips stop-lights create. This isn't metal from the train blocking my signal, the phone that the music is getting streamed from is in the leg pocket on my carpenter pants. I would be worried about this phenomenon not only engaging my brakes when I don't want them engaged, but also preventing them from working as well. This isn't just failure after poor maintenance and abuse, this is every single stoplight in the Houston area and I'm sure other places as well.
I'm glad they aren't looking to deploy these yet, and I hope they don't. It's hard to beat the simplicity of a simple wire. It's also the same reason Soviets in MIGs could pull off maneuvers our pilots in F-whatever planes couldn't because the electronics wouldn't allow them to.
The preceding post was not a Slashvertisement.
but there are military helicopters which use fly-by-wireless at a significant mass savings. All that mass that isn't in copper/insulation/supports can go into payload or armor or other "useful" stuff.
Can you provide a reference for this?
With as much RF shielding that military radio/navigation equipment gets for resistance to jamming, I'm really surprised that they'd go fully wireless for control systems.
Can the motors in question apply the same amount of pressure that can be produced by squeezing the human hand?
Since they were designing an impractical proof-of-concept, I think it's safe to say that they could easily come up with motors that can provide the same (or more) pressure as human hands. When you have no real weight or energy concerns, anything is possible.
Now why do need to have a Battery to have working brakes? On a bike?
on trains at least the brake systems fails to a stop state but any ways on a train why not have a cable any ways you need them to power it and the pipes for the air system.
Cranes, drawbridge motors, and industrial machinery all need power cables and or hydraulic tubes and running cat 6 / other data cables is next to nothing in scale.
I'll stick to my track bike, thank you, which has a single, cable-operated brake that I use for emergency stops two or three times a year.
"Who controls the past controls the future. Who controls the present controls the past." -- George Orwell
Actually, in this context, "breaks" might be right.
Quidnam Latine loqui modo coepi?
If anything, the system should have used optical transmission. It'd be fairly interference- and jam-proof, had they decided to use a modulated transmission -- modulated using a carrier and a PRN code so that multiple bikes in vicinity would not interfere with each other. GPS satellites do transmit at the same frequency, after all, and there's no interference.
Due to small distance between the handlebar and the actuator/receiver, you'd need a fairly powerful laser system to do any sort of large-area jamming, and any small-scale jamming would need tracking -- of course it can be retrofitted to existing, say, tracking camera systems they have on police choppers. Yet, if the transmission was done using two layers of PRN: PRN-driven frequency hopping for the optical subcarrier *and* a digital PRN code, then it could be pretty much jam-proof unless you knew the generator settings. Heck, it the PRN could come from a cryptographically secure generator, where it's "nigh impossible" to know the future code sequence without physically hacking into the box.
I don't think I would want to use any sort of a wireless brake system that uses radio, especially an unlicensed ISM band. It's a fairly preposterous idea. You could trivially swamp the receivers in bikes on a whole block using off-the-shelf radio gear with a concealed antenna. With an optical system, it's line-of-sight. A tinfoil umbrella is all you need to shield it from airborne jamming ;)
A successful API design takes a mixture of software design and pedagogy.
I skimmed the PDF of their report. It's quite interesting, and despite the armchair quaterbacking on Slashdot, these people have done a pretty good job of using a life-critical system for testing out high-reliability wireless connections.
The one issue I have with their work is that they imposed an acceptability limit of 250 ms -- that is, there could be no more than 250 ms lag between a change in command (squeezing more or less hard on the brake handle) and the brake shoes actuating. That seems quite long, even unnecessarily so.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
I guess the real reason the article reads like a solid WTF is that they are, supposedly, computer scientists with no experience in RF, controls, or safety-critical system design.
A successful API design takes a mixture of software design and pedagogy.
This could have been done for decades, it's just that nobody did because it has no advantages over conventional cable brakes and a shit-ton of safety issues.
"When information is power, privacy is freedom" - Jah-Wren Ryel
I think it would be great to hack these, and then remotely trigger them for laughs.
Yeah, for some things I'll take the old-fashioned mechanical control systems.
-Styopa
Doesn't mean you should.
http://www.wired.com/gadgets/miscellaneous/news/2008/07/shimano?currentPage=1
Yeah, brakes are a different class, since they're a safety requirement rather than a nicety. It's especially nice in shifters, because it takes some of the tedious adjustment out of the picture.
Mostly, I think it's about clean aerodynamic profiles and simplicity: no wires means nothing to adjust. They've had batteries on bikes for a while, so this isn't novel on that score.
It's definitely for high-end road bikes only, real top-of-the-line stuff. I don't know if it will make a difference at that grade or not (it's way out of my league) but it sounds as if the doomsayers don't really know what it is high-end cyclists want and why. Yes, there are issues to be worked out, but I'm pretty sure they're aware of that.
It's not a question of not wanting to share the road, it's a matter of being pissed off at idiots who constantly ignore red lights and stop signs, swerve back and forth between lanes (including the oncoming ones), don't signal or even look before turning across in front of traffic.
Yeah, I hate car drivers too, but there's not much you can do about them, so I just learn to live with it.
Is 1563649 a prime number?
I wonder if these guys are building reasonable security into their wireless connections?
Or are they doing what everyone else does, and create a wireless technology
and the security in later.
When you have no real weight or energy concerns, anything is possible.
Well, not quite. Obviously, this is POC, but I bemoan that since systems like Di2 work very well, but few use them because they add too much extra weight.
Not quite what? The designers of this system weren't trying to build a workable wireless brake system for bikes, they were only interested in the wireless control system, hence they had no constraints at all for the actuator motor - they could have used an 15 pound ABS actuator from a car powered by a 20 lb car battery and still met their design goals.
From TFA:
In this paper we are looking at a very tiny control problem
of precisely that sort. It is safety-critical, has hard real-
time requirements and does not have an obvious fail-safe
state.
But now you can use your android device or Ipa/od Device to stop your bike!
I know someone who bikes a lot (From california to Massachusetts this year.) He has a wireless bike computer, which basically measuses each time your wheel goes around, and sends it wirelessly up to a little display on the handlebars. This worked great till he turned on his LED light, then the link was severed. By repositioning the light he could get the computer to work mostly. But computer isn't a key to functionality as brakes.
I think as a proof of concept this is fun, I would caution against testing at night.............
Bikes are a interesting engineering compromise between "make it state of the art" and "keep it simple/exposed/fixable" engineering. We'll see if hub brakes/ belt chains and other "advances" make a mark..
And they take up the WHOLE LANE with their cars.
but it does not hurt to keep all the other failure modes of mechanical brakes in mind (which may or may not be addressed by this device). These include:
- forgetting to reattach the cable, or deactivate the quick-release after service
- cable separates from soldered end
- binding nut not tight enough
- ice in cable housing makes cable immobile
- wet rims
- iced rims
- melted brake shoes
- melted coaster brake
- broken chain (on a fixie)
- derailed chain (on a fixie)
- brake-worn-rim separation
- internal hub leaks oil onto a disk brake rotor
And you might think, "oh, but this would never happen (to me)", except that most of these things happened to me at one time or another, though never with serious consequences. And I've done some bicycle maintenance/repair sessions with boy scouts and church groups, and my-oh-my-oh-my. The real world is not an orderly place.
Our uneasiness with the idea of wireless brakes has a lot more to do with illusions of control.
That said, bicycle electronics don't get an easy life. The vibration is terrible, and bikes get used in the cold and the wet, and sometimes they get road salt on them.
Optical transmission? How? By line-of-sight? That might work in good weather, for the front brake. But how are you going to get it to the back brake? And what if a drop of water or mud gets on the sending or receiving unit? Optical fiber is still a cable, so that's not a real change, either.
RF could work if more than just channel crosstalk is eliminated as a source of unreliability.
Instead of it being completely wireless, find a way to send the signals through the frame of the bike. Why use air when another conductive medium is available? I realize the experiment was specifically about wireless, but this application seems more suited for the same kind of "wireline" technology that lets you use your home power lines for ethernet.
My bike has hydraulic brakes. They're really nice, they're so responsive.
(Apparently it's complicated to bleed the liquid etc, but that's shouldn't be necessary. I've ridden 8000km and so far the only maintenance I've needed to do to the braking system is to replace a set of pads, which took about 5 minutes.)
What could possibly go right with this idea?
Sending and receiving signals. The whole subject has been thought about for more than 50 years. Seems more like an undergraduate learning exercise to me rather than any new discoveries. The summary article dwells on synchronous verses asynchronous. All very obvious to me, nothing new.
There is quite an ingenuous way of getting a small (<10mm^2) optical receiver to be insensitive to droplets of water, splotches of mud, etc. All you do is place it inside a larger dome ;)
The remote for my iPod dock works if you point it anywhere in the same room. It also works very well if you open the door, go to the hallway, and point it almost anywhere in the hallway, as long as you're not too close to the wall. Heck, my desktop lamp, pointed straight at the table, illuminates almost the whole room. How about that!
</sarcasm>
Again, jamming RF is trivial with off-the-shelf components. Jamming optical is not trivial at all.
A successful API design takes a mixture of software design and pedagogy.