A trio of web developers from New York and I formed a team, but they took off early to have a bite to eat and attend a tequila tasting, so I pressed along on my own. We set out to build a system that would use a light sensor (eventually two light sensors) and a servo to track the position of a flashlight.
After about two hours of work, it was working! See the video below.
I spent the last 45 minutes or so tweaking the code to smooth the motion of the servo and light sensors by adding hysteresis and a delay after writing a new position to the servo before re-starting the main loop (and re-reading the analog values from the light sensors).
With more time, there are a handful of straightforward improvements to be made:
- Add gain to track faster when the light is moving quickly.
- Build a more symmetrical light guide (something not pieced together with a slip of paper and scotch tape).
- Perform a more careful calibration of the light sensor circuits.
- Add some signal conditioning to the light sensors to take advantage of the full input range of the ADC (analog to digital converter) on the Arduino board.
- Refine the servo control to improve motion stability and device reliability.
Some of the other teams had a lot more software/application development background than I did, and put together some really neat projects. I think my favorite was an R/C car that was driven by an Arduino that interprets text messages. Anybody could send a text message with an 's', 'g', 'l', or 'r' (for stop, go, left, right) and make the car drive around. I think they tied for 3rd place, but if the judging were based on positive audience reaction, they would have been the clear winners.
All in all, it was a fun evening and a nice introduction to the Arduino platform. I anticipate some interesting projects in the future; making the Arduino work with other circuitry, sensors, and actuators to do interesting things.
If any of the other hackfest participants find their way to this blog, please do feel free to leave a comment or shoot me a message if you need some awesome hardware added to your next project.