I went with just a few discrete steps in the distance LED colour so that it might be more noticeable as you approach the cache. There are a couple of discrete steps in between. When you are far away from the cache, the LED is blue and when you’re closer, the LED goes red. You also get a ‘distance LED’ (which is a kind-of purple in the photo).

When you get a GPS position fix, the compass LED turns green as does the GPS status LED. The GPS status is indicated by the LED currently illuminated yellow. The blue LED in the circle pattern is showing information from the compass only since the GPS hasn’t got a position fix yet. Once the gadget is programmed with coordinates, when you fire it up you will see something like this: In UseĪs it stands you need to hard-code the GPS coordinates into the Arduino program for each different geocache and then re-program the Arduino. I built the gadget in a cigar box since a) I had some around (no, I don’t smoke) and b) it’s a nice steampunk/retro kind of touch although, clearly, sending a very bad message to children about smoking. Why not use the neopixels to make a compass display with some status LEDs thrown in for good measure? Then I could throw away the fragile and boring LCD display and, hey, it has blinkenlights so it must be good, right? Of course, I didn’t quite finish it in time so instead they got sent off with a relatively rugged Garmin eTrex with my fingers crossed (not worrying about the children, but my expensive GPS receiver, natch).Ībout a year later I ordered some neopixels / RGB LEDs to play with and the idea came to me to remix the reverse geocache project into something a bit different. and started to build one in time for some visitors with kids.

I saw a reverse geocache box on the interweb with Arduino, LCD display, servo motor, GPS, etc. I had kids in mind – rather than sending them off running around with your bazillion dollar iPhone in their hands, use this gadget instead.

For fun I made a dedicated geocache toy from an Arduino, GPS receiver and electronic compass modules and neopixels (RGB LEDs).

Opensprinkler github dan