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Speed of Sound Is Too Slow For the Olympics 255

Posted by Unknown Lamer
from the whose-phone-was-that dept.
Hugh Pickens "For decades sports-event organizers have placed speakers behind athletes to convey the sound of an actual pistol but they found that even though the noise came through the speakers all at once, athletes continued to wait for the 'real' sound, ignoring the sounds that came through the speakers ever-so-slightly slowing down the farthest athlete from the gun. Now Rebecca Rosen writes that when the Olympic runners take to their positions on the track later this week, they'll crouch on the ground, ears pricked, and wait for the starting beep played by a 'pistol' that's not a pistol at all, but something more akin to an electronic instrument with only one key. The pistol itself is silent." Read on for a bit more about the difficulties of timing people with superhuman reaction times.
"A conversation with sprinter Michael Johnson at the Sydney Olympics caused Peter Hürzeler of OMEGA Timing to realize that even with speakers, the speed of sound was still slowing down the farthest athletes. Johnson's reaction time, Hurzeler said, 'was 440 thousandths of a second. Normally athletes leave between 130 and 140 thousandths of a second. ... I asked him, why did you have such a bad starting time?' Turned out, Johnson was in the ninth position, and the sound of the gun was reaching him too slowly.

"In addition after a four year developmental process, a new false start detection system is being introduced this year that will abandon movement in exchange for 'measurement' of pound-force against the back block to determine sprinters reaction times. 'We are measuring the time between the starting gun and when the athlete is moving because to leave the starting block they had to push against and this power is very high' says Hurzeler. 'We did a test last year with Asafa Powell and he was pushing 240 kilograms (529 lbs.) [so] as soon as he gives the time to push against the starting block, it means he will like to leave and we are measuring this in thousandths of seconds and if somebody is leaving before one hundredth thousandth of second, it's automatically a recall, it's a false start.' In track every event is timed to 1/10,000th of a second, and Omega takes 2,000 pictures per second from right before the start of a race to its finish, as backup.

"New touch pads, starting blocks, and timers have also been introduced for swimming."
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Speed of Sound Is Too Slow For the Olympics

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  • Not sure if real pistol fired next to the athletes is too easy or not geek enough...
    • by Joce640k (829181)

      In 2012 it doesn't seem impossible to put a speaker+light in all the starting blocks.

      • by vlm (69642)

        In 2012 it doesn't seem impossible to put a speaker+light in all the starting blocks.

        In 2012 it doesn't seem impossible to put an individual timing gate on each lane so sub millisecond differences in sound propagation don't matter, yet they'll be running "about the same time" close enough to meet the olympic goal of pointless dramatic theatrics.

        Maybe someday we'll have "mass produced electronics"...

        • by CastrTroy (595695)
          Exactly, Why not just time them from when they leave the gate, instead of trying to test their reaction time at hearing the pistol. This is how ski races are timed (ndividual events anyway). The EKG countdown is just to let you know when to go, but the timer doesn't start until you leave the gate, and the timer stops when you cross the finish line. I think running races would be much more interesting if we were only measuring the time they spend running, and didn't worry about how fast they reacted to sou
        • Re:Not sure... (Score:4, Insightful)

          by magarity (164372) on Wednesday August 01, 2012 @10:10AM (#40842695)

          Sure, that's easily accomplished technically. Except that's not the point of these particular races. Some races are against the clock, many of the cycling races for example. Shorter races, however, aren't against the clock; they are racer against racer. The clock is just there to compare across races and time. So, since the racers are racing against each other, not against the clock, there is all this fussing over starting at the same time.

    • Will it matter that much if Usain Bolt destroys the field, as is the most likely outcome?
  • They should just use a light instead of sound. Even at school we waved a flag to start because if we went by sound it would introduce an error into the timing.
    • Re:Speed of light (Score:5, Informative)

      by pushing-robot (1037830) on Wednesday August 01, 2012 @07:21AM (#40840829)

      Because we typically react a bit faster to auditory stimuli.

      (around 30-50 ms faster than visual stimuli)

      • Re:Speed of light (Score:5, Informative)

        by SorcererX (818515) on Wednesday August 01, 2012 @07:31AM (#40840905) Homepage
        Indeed, do you have a source for the 30-50 ms faster figure? My source says 80 ms faster than visual stimuli. Source: "We ran a t-test based on the tabulated average individual reaction times to each stimuli, and established that the mean average individual reaction time to light (0.28005 sec.) was statistically significantly different than the mean average individual reaction time to sound (0.20407 sec.; P-Value= 1.79E-07 .05, the statistical level of significance)." ( http://www.colorado.edu/eeb/courses/1230jbasey/abstracts%202010/37.htm [colorado.edu] )
      • by GNious (953874) on Wednesday August 01, 2012 @07:45AM (#40841029)

        I suggest electrical stimuli - 240v should suffice

        • It would certainly make spectating a lot more interesting! You could kill two birds and fill up some of those empty seats.
        • by vlm (69642) on Wednesday August 01, 2012 @09:07AM (#40841871)

          I suggest electrical stimuli - 240v should suffice

          Better be DC or high freq AC (like a tesla coil) because an AC waveform has a longer wavelength than the kind of measurements they're already complaining about.

          For example a anal probe activated at a voltage zero crossing would take around 5 ms to reach peak voltage at 50 hz, but the americans would whine because they're used to 60Hz which only takes 4ms to reach peak voltage. And the other competitors would whine because the 220 volt probe would reach the 110 volt level that the americans train with in only about 2 ms, whereas they're used to waiting until a voltage maximum at 5ms to react. As you can see even low frequency RF aka "power electronics" is all rather complicated. This is before power factor correction, where athletes with inductive or capacitive digestive systems would lead/lag and the nervous system is inherently current mode logic anyway (or is it? Some MD or bio guy needs to weigh in) (hmm, digestive system is shaped inductively all curly and stuff, but digestion is all about capacity aka a capacitive reactance... anyone other than space alien abductors got a smith chart plot of a human digestive system based on probe data?)

      • by dcw3 (649211)

        Would it matter, since it would still be a level playing field?

      • Re:Speed of light (Score:4, Informative)

        by dcw3 (649211) on Wednesday August 01, 2012 @09:57AM (#40842521) Journal

        Just wanted to add...have you been to a drag strip?

    • by ArcherB (796902)

      They should just use a light instead of sound.
      Even at school we waved a flag to start because if we went by sound it would introduce an error into the timing.

      Back in my track days, we were taught to go by the smoke of the pistol, not the bang. When did this change?

    • by Joce640k (829181)

      I'm guessing that head-down is a better posture for a sprinter when he's in the blocks.

  • First! (Score:3, Funny)

    by yorgo (595005) on Wednesday August 01, 2012 @07:11AM (#40840759)
    Appropriate, for once...
  • by RivenAleem (1590553) on Wednesday August 01, 2012 @07:17AM (#40840803)

    Why not just lights? Works for F1.

  • When acting as a timing judge for swim team events, we have always been told to watch for the strobe flash from the start signal. It is supposed to be much more consistent.

  • Overkill (Score:2, Insightful)

    by Anonymous Coward

    Why not just move the starting gun to behind the athletes? The further back it is placed, the more equal the distance to each athlete. It doesn't get as much media attention though.

    • Meh. Just point the gun at the athletes, and they'll easily make up for the few hundreths lost at the start.

      Win-win, I'd say.

  • by sturle (1165695) on Wednesday August 01, 2012 @07:27AM (#40840867)
    This reminds me of my time in the navy. There was a minimum requirement for everything, including 60 meter sprint. I ran it once, and got clocked in 1/10th of a second to late. Fearing I would have to run 60 meters once more, I protested because the starter gun was at the finish line! The sound would take almost exactly 1/10th of a second to reach the starting line from the finish line, I argued. They had to accept the protest, of course, and I made the requirement exactly.
  • ...so why not give runners a time bonus if they are in a later lane ? Start 30 m from the gun, get a 100ms bonus. Sounds simple enough, no ?
  • hamster wheels! (Score:5, Interesting)

    by catmistake (814204) on Wednesday August 01, 2012 @07:29AM (#40840887) Journal
    How about placing runners in some kind of human-sized hamster wheels with clutch mechanisms, so that all runners can already be running at top speed for some short period prior to the actual start of the race, at which time all of the clutches are simultaneously disengaged, so all runners start at full their full stride and their full speed at the same time? This would change the dynamics of racing because it would remove reaction time as a competitive element from the race. But what is a race? Is it to see who has the fastest reaction time, or who runs the fastest, or both?
    • what is a race? Is it to see who has the fastest reaction time, or who runs the fastest, or both?

      Obviously both are a part of this type of race. Previously due to necessity, but now in the ages of high speed cameras and other tech, just due to tradition. If they simply wanted to see who could do the fastest 100m from a flying start, they could just let everyone start whenever they want, and measure their performance from 10m to 100m.

  • by Anonymous Coward on Wednesday August 01, 2012 @07:34AM (#40840929)

    There are 8 lanes on a track, each of which are 1.27 meters wide. There are 7 lane widths between a head in lane 1 and a head in lane 8. This works out to 8.89 meters. The speed of sound is 340.29 meter/sec. The leads to a worst case difference of .026 seconds between lane 1 and lane 8. The difference between bronze and gold in the 2008 Olympics Men's 100 Meters is 0.22 seconds. So at first it seems to not be an issue, but the difference between bronze and 4th place was .02 seconds. This indicates that lane position and the speed of sound could have an effect on the outcome of an event.

  • by pev (2186) on Wednesday August 01, 2012 @07:49AM (#40841055) Homepage

    So. Rather than have the pistol in line with the row at one side, how about having it in the middle halving the dis-advantage at the extreme(s). Even better, have the pistol central but step back 10 - 20 foot or so and that reduces the differential even further. Seems more practical and a lot more inexpensive than a super dooper electronic system.

    • Did you think the Olympics(TM)(C)(R) were about competition and fairness instead of about money, bribes, kickbacks, and the worst kind of patriotism?

    • by crow (16139)

      And then they would have to adjust the timing for the false start detection to be based on when the sound reaches the athletes.

    • by nblender (741424)

      You could eliminate the error entirely by arranging the runners in a circle and put the pistol in the center. Make it up to the judges whether the runners face in or out.

  • by MaWeiTao (908546) on Wednesday August 01, 2012 @07:55AM (#40841099)

    What confuses me is that the story says they're using speakers, meaning every player hears the sound at the same time. So where's the issue?

    It seems that the speakers convey the sound of a guy with an actual gun further behind. But why aren't the players training themselves to react to the first sound, disregarding the real noise. More importantly, why the hell is there even a real gun out there if they've got the speakers? They couldn't have started using a prerecorded sound years ago?

    It appears to me that the real story here is that these officials are so slavish to hopelessly outdated traditions that they'll continue sticking to them even long after it's become evident that it's detrimental. It reminds me of FIFA's long time refusal to accept replays or goal line technology.

    • What confuses me is that the story says they're using speakers, meaning every player hears the sound at the same time. So where's the issue?

      It seems that the speakers convey the sound of a guy with an actual gun further behind. But why aren't the players training themselves to react to the first sound, disregarding the real noise. More importantly, why the hell is there even a real gun out there if they've got the speakers? They couldn't have started using a prerecorded sound years ago?

      It appears to me that the real story here is that these officials are so slavish to hopelessly outdated traditions that they'll continue sticking to them even long after it's become evident that it's detrimental. It reminds me of FIFA's long time refusal to accept replays or goal line technology.

      You've got that right. Look at the electronic "pistol" picture in the article. They designed it to look like a large gun. Why not just a small button held in the hand?
      Better yet...nothing. Just have the speakers play the "start" sound and the runners take off. They're looking at the ground when in the starting blocks anyways, not the guy standing off to the side.

  • ... is a 12-step program for these folks, (all puns intended).
  • by fa2k (881632)

    There was an article on /. where it was argued that journalists should use more jargon if it helped convey the message. After reading "thousandth of a second" *four* times in the summary, yes, please, just say millisecond!!

  • Stick an electrode up their arse. When it is time to go, zap them. About 50,000 volts will do nicely.

    All joking aside, they really could just use lights. Or is the speed of light too slow as well?

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