Our prototype Instant Replay system
Posted: Sun Feb 09, 2014 7:15 pm
https://youtu.be/szJckeUe58I
After building our own timer using a Netduino platform, I turned my attention to building an arduino based instant replay system. At first, my thought process was to entail pulling the video from a high speed camera and then re-encoding it to play back in slow motion, however that solution became expensive and impractical for short races. Then, it occured to me, my family has a four year old Sony CX500 Handycam which can be controlled via infrared. A little coding later, and I've come up with this working prototype. The video stays completely on the camera, thereby not requiring anything other than the arduino, a few LEDs, photocell and laser. There is less than $35 in electronics in the whole setup.
Also, since this video was recorded, I have discovered an extra special nicety about this particular camera. It has a 3-second "Smooth Slow Record" feature, which makes it a truly high speed camera, capturing approximately 240fps for 3 seconds, which of course is plenty of time to catch a derby finish. So, instead of deleting the video after each race, I'm keeping each 3 seconds of high-speed footage, which is approximately 50MB of space. The 32GB on the camera should allow us to record over 600 races, which should be gracious plenty! When the 3 seconds of "Smooth Slow Record" footage is played back in "slow" scan, it takes 60 seconds to play, giving us a 20:1 slowdown. The cars practically crawl across the finish line at this pace, making it a fairly good backup plan in case our track timer breaks. The fact that the unit is completely automated makes it even better.