100m race clock

I was just wondering I anyone has ever seen a rig that you could use at home, during exercise, to do precise measurement of the time it takes to run 100m (eg.)? It's a little awkward to do with a stop watch in your hand and there is lots of room for error. You would need a beep to tell you that time has started, and some way to stop the time once you have reached the desired distance. thanks Alan

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Kiteman9 years ago
At school we use a pair of light-gates to measure speeds over a known distance - it starts counting when you break the first beam, and stops when the second is broken. A larger version would sort you out.
100m as in.... meter? min? mile?
alanrb (author)  Weissensteinburg9 years ago
sorry for not being more clear. I was thinking of 100 meter, like the track event. And it would need to be accurate down to at least 10th of a second. Just for fun though, to keep kids moving and challenging them selves, but something that could be done alone. thanks
gyromild9 years ago
When you said "use at home", what exactly do you mean? Running in place, running in circle, running in your backyard? If you plan to run in an open space (ie your neighborhood park), a straight line sprint of 100m. You could use a digital wristwatch (with alarm) + a stop watch rigged with tripwire. 1) Check your wristwatch, as soon as it hits a rounded minute (ie 09:14:00), start your stop watch. Make sure both are in-sync to the second. 2) Set the alarm on your wristwatch to 09:24:00.. that gives yourself 10 minutes to rig the stopwatch on the finish line, then walk to the starting line. 3) When your wristwatch's alarm sounds, run like hell to the finish line. 4) You time would be: whatever time lapse on the stop watch minus 10 minutes. I have a pretty low-tech picture in my head of stopwatch rig. I could draw it if you want..cheers
NachoMahma9 years ago
. If you have a consistent stride, maybe you could figure out someway to use a pedometer to stop the timer when you've traveled 100m. . There must be an easier way, but I can't think of anything else that wouldn't require some kind of trip mechanism set up on the track or a second person.