I started to develop a race timer with start and stop gates - IR beam breaking. I have developed the software, but don’t have the time to complete the hardware. If anyone is interested in doing a hardware project, you may contact me at firstname.lastname@example.org
This sounds an awful lot like this project: https://community.spark.io/t/stopwatch-for-pinewood-derby/3486
Perhaps some of it may be of use to you, take a look ;)!
It’s a competitive device to the one at the link I’ll put at the end of the message. BUT… I use a smartphone as the intelligence. The competitive product is $1800. They are used for dog agility where people spend tens of thousands of $$ to run and often, placement will be decided by 100ths of seconds. There are two timer gates (start and stop) and each has 6-8 IR sensors for beam breaking indication (small, medium, and large dogs). One of the problems is that the SPARC must build the WiFi network and one of them must be an access point. I could probably do it myself, but I’m currently employed doing other things and don’t want to put in the time and experimentation. Here’s the link to the competitive product… http://farmtek.net/agility_events.htm
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