April 5, 2012 AT 1:11 pm

Arduino based swim timer for night swimmers


A swim timer for night swimmers @ DougsDIY via Twitter

swim with a triathlete group in an outdoor pool at 6AM three days a week. For half the year I can see stars when I start swimming. What I can’t see in the dark is the analog clock to check my pace on 100 meter laps.

To solve this problem I designed and built a portable digital timer with LED display. The 4-digit 7-segment display is large enough to see from 10 feet away so I can read it without stopping. The timer is encased in a transparent and waterproof polycarbonate tube so that I don’t have to worry about it getting wet or falling in the pool. In fact you can take it to the bottom of the pool and it won’t leak. Normally it just sits on the edge of the pool where I can see it.

There are a variety of LCD swim timers available that are fine for day swimmers. This timer is for night swimmers.


1 Comment

  1. I’ve recently started swimming laps in my backyard pool before bedtime for exercise (plus it helps me fall asleep more easily). I wanted a clock by the pool so I could time my workout but would need something that could be seen at night and could be weatherproofed. So this project is a nice idea (and I happen to have a spare Arduino and lots of 7 segment led displays in the junk box). I’m thinking one of your water proof Otter boxes might be good for this project. I was also thinking more along the lines of a clock than a timer, so maybe I’ll add a chrono-dot.

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