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Scientists Build Wireless Bicycle Brakes

Posted by Soulskill on from the oh-the-possibilities dept.

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.'"

22 of 213 comments (clear)

  1. Awesome... by AngryDeuce · · Score: 5, Funny

    I haven't had a head injury in a while, where do I sign up to try them out?

    1. Re:Awesome... by Anonymous Coward · · Score: 4, Interesting

      I haven't had a head injury in a while, where do I sign up to try them out?

      On a slightly more serious note, where can I buy some? I'll need about 3 dozen before the next local marathon bike race.

    2. Re:Awesome... by grimmjeeper · · Score: 2, Funny

      Cut him a little slack. He may still be suffering from one of the other head injuries he had a while ago...

    3. Re:Awesome... by OeLeWaPpErKe · · Score: 3, Funny

      And where do I buy the signalling device ? I would love to mount this on the side of my car, having all bikes around me lock up entirely, with hilarious results.

      Joking aside, I do hope this guy thought about security.

    4. Re:Awesome... by Crudely_Indecent · · Score: 3, Insightful

      I hope there is some sort of Make sure you mix up the levers and calipers so the radio pairs aren't installed together on the same bike.

      Yeah, no thanks. This sort of technology adds multiple potential points of failure to a system that is currently reliable and simple.

      Whereas a bicycle brake system can experience a cable failure (among others which are shared with a wireless system, such as pads) a wireless system can experience transmitter failure, receiver failure, radio interference, battery failure (transmitter or receiver). This team tries to mitigate that potential failure by adding more transmitters. That reminds me of a SNL skit - Christopher Walken "More Cow Bell"

      In my time as a cyclist (3 decades), I've only experienced brake communication failure (broken cable) a couple of times - after which I learned to stop buying cheap cables and I've never experienced brake failure again.

      I realize this is not a product that will likely see the light of day. It was an exercise in the reliability of critical communication as indicated by a quote early in TFA:

      "Wireless brake" and "hit by a truck" sound the same to a cyclist

      --


      "Lame" - Galaxar
    5. Re:Awesome... by TheRaven64 · · Score: 2

      Why RTFA? The summary makes it quite clear. It's actually a very good test application. Bicycle breaks are mechanically simple and cheap to construct, but require the same sort or control latency as a lot of aerospace applications. It's a lot cheaper to stick an experimental control system on a bike than an aircraft, and if it doesn't work it's probably a lot less painful...

      --
      I am TheRaven on Soylent News
    6. Re:Awesome... by Migraineman · · Score: 5, Insightful

      Most of the responses so far are people getting hung-up on the example and responding "wireless brakes on a bike are teh shitz." If you read the PDF, they're pretty clear that the experiment is about real-time control systems using wireless communications links. The wireless bike brake is a convenient structure to do some real-world prototyping, and provides some environmental bounds (response time, lag, bandwidth, etc.) that ratchet this up one level above being a purely academic exercise.

      That said, the authors are faced with the horrible reality of wireless links - they are completely unreliable. Fundamentally. Period. The aether is a shared medium, and as such, you have to deal with collisions from other transmitters and interference from unintentional radiators (microwave oven, I'm looking at you.) The objective response time in this experiment is 150mS in the wireless link, and 100mS in the physical actuator. Ignoring the actuator time, 150mS is an abstract number without context. If you're brewing coffee wirelessly, 150mS to close the loop on the temperature control is effectively "instant." [no pun intended] However, if you're measuring RPM feedback on a turbine shaft, 150mS may be an eternity.

      If you're placing the wireless link in the feedback path of a control loop, which these guys are doing, you have to account for the characteristics of the wireless link as part of the control loop stability analysis. Modeling packet loss and transmission delay as the equivalent phase shift and frequency characteristic of a classical analog component can be quite challenging. Further, the characteristics of interference sources may place you squarely in the "doomed from the start" category. If the above mentioned microwave oven can impair your wireless link for the duration of a bag of popcorn, your 150mS response time is irrelevant.

      Wireless links and hard real-time control systems go together like fish and bicycles do.

    7. Re:Awesome... by Fnord666 · · Score: 2

      The aether is a shared medium, and as such, you have to deal with collisions from other transmitters and interference from unintentional radiators (microwave oven, I'm looking at you.)

      After that we need to start talking about intentional interference that will screw your control system. Jamming a signal is fairly trivial if the control system is going to be reasonably priced. You will also see a lot of late stage design change failures when someone in a different department decides that an intervening panel needs some extra thermal protection and adds a metal backed sheet of insulation.

      Just tag this "DoomedFromTheStart".

      --
      'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
    8. Re:Awesome... by Crudely_Indecent · · Score: 3, Funny

      bicycle's pollution control system

      That's a different industry - Fruit of the Loom makes the filters, and Gas-X makes the fuel system additive.

      --


      "Lame" - Galaxar
    9. Re:Awesome... by yurtinus · · Score: 2

      Cars aren't fly by wire for weight savings as much as for efficiency - a throttle cable vs servos is sort of a wash. However, computer controlling your acceleration curve and fuel flow can give more efficient results when the driver mashes the pedal.

      --
      +1 Disagree
    10. Re:Awesome... by gstoddart · · Score: 2

      As somebody who has crashed on a bike: Crashing on a bike is not that bad.

      Well, we just had someone killed recently because someone flung open a door, nailed the cyclist, knocked them into traffic, and they got run over.

      Oddly, your one data point doesn't necessarily cover all cases of crashing on a bike. There are plenty of circumstances where crashing on a bike is anything but "not that bad".

      And, if you've ever seen the guys doing downhill ... well, tell them it isn't all that bad or damaging to fall off. Hell, at lower speeds on tight single-track I wear some body armor ... I won't even ride in traffic. The drivers more or less treat you like you're using their space, and will come awfully close to running you over without a second thought. In fact, they're probably cursing at you while they're inches away from killing you.

      I wouldn't downplay the severity of crashing on a bicycle.

      --
      Lost at C:>. Found at C.
    11. Re:Awesome... by davester666 · · Score: 2

      There already is a backup braking system on your bike...think Flintstones...

      --
      Sleep your way to a whiter smile...date a dentist!
  2. Works GREAT! by aardwolf64 · · Score: 2

    Works GREAT... until the battery dies and you hit a car.

    1. Re:Works GREAT! by AngryDeuce · · Score: 2

      And think of all the fun when someone figures out a way to mimic the signal with another device! We'll know the future has finally arrived when a bully can fling a kid off his bike from across the street...

    2. Re:Works GREAT! by Jaqenn · · Score: 2

      No, you know the future has finally arrived when the most successful bullies torment their victims with intelligence and technology instead of burly muscles and indian-burns.

      --
      You are awash in a sea of fiercely stated opinions. Obvious exits are: 'File->Quit', 'Reply', and 'Page Down'.
    3. Re:Works GREAT! by MozeeToby · · Score: 2

      If you think bullies are all about beating people up and taking their lunch money, you haven't spent any time around teenage girls or any adults in an office environment for that matter. Give people power over other people and some number of them will abuse it. In grade school that power is in terms of hitting puberty a few years before their peers and having extra muscle mass. People associate that with bullying because the effects are obvious and the kids are least equiped to deal with it. But even by high school you can have social bullies, technical bullies, and, yes indeed, even technology bullies.

  3. Already here for cars by Quila · · Score: 2

    Welcome to OnStar, can I help the police violate your rights today?

  4. Re:fly-by-wireless by Joce640k · · Score: 2

    "Brakes". The word you're trying to write is "brakes".

    --
    No sig today...
  5. Stop whining by hackertourist · · Score: 4, Insightful

    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?

  6. Jackass by hack++slash · · Score: 4, Funny

    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.
  7. They've had this for shifters already by jfengel · · Score: 2

    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.

  8. Re:Hmmmmm... by SleazyRidr · · Score: 2

    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?