Planet Arduino

For those who love to hike, no excuse is needed to hit the woods. Other folks, though, need a little coaxing to get into the great outdoors, which is where geocaching comes in: hide something in the woods, post clues to its location online, and they will come. The puzzle is the attraction, and doubly so for this geocache with an Arduino-powered game of Hangman that needs to be solved before the cache is unlocked.

The actual contents of a geocache are rarely the point — after all, it’s the journey, not the destination. But [cliptwings]’ destination is likely to be a real crowd pleaser. Like many geocaches, this one is built into a waterproof plastic ammo can. Inside the can is another door that can only be unlocked by correctly solving a classic game of Hangman. The game itself may look familiar to long-time Hackaday readers, since we featured it back in 2009. Correctly solving the puzzle opens the inner chamber to reveal the geocaching goodness within.

Cleverly, [cliptwings] mounted the volt battery for the Arduino on top of the inner door so that cachers can replace a dead battery and play the game; strangely, the cache entry on Geocaching.com (registration required) does not instruct players to bring a battery along.

It looks like the cache has already been found and solved once since being placed a few days ago in a park north of Tucson, Arizona. Other gadget caches we’ve featured include GPS-enabled reverse caches, and a puzzle cache that requires IR-vision to unlock.

Thanks to [Dan Wagoner], who built the game upon which this is based, for the tip.

While getting geared up for geocaching [Folkert van Heusden] decided he didn’t want to get one of those run of the mill GPS modules, and being inspired by steam punk set out and made his own.

Starting with an antique wooden box, and adding an Arduino, GPS module, and LiPo battery to make the brains. The user interface consists of good ‘ole toggle switches and a pair of quad seven segment displays to enter, and check longitude and latitude.

To top off the retro vibe of the machine two analog current meters were repurposed to indicate not only direction, but also distance, which we think is pretty spiffy. Everything was placed in a laser cut wooden control panel, which lend to the old-time feel of the entire project.

Quite a bit of wire and a few sticks of hot glue later and [Folkert] is off and ready for an adventure!

Anyone remember the game Myst? Well, [Michael] and his girlfriend have been playing quite a bit of it lately, so for her birthday, he decided to make her something inspired from it.

For those unaware of the classic that is the Myst series, it is a set of games that started back in 1993 where you assume the role of the Stranger who gets to explore other planets (called Ages) to solve various logical and mechanical puzzles.

Anyway, [Michael] got his girlfriend tickets to visit GC319QK (a geocache site requiring diving) — since the gift is a relatively small token, it was logical for [Michael] to make a fancy box for it — and that’s exactly what he did. It’s a peculiar little wooden box with LEDs, a button, a latch, an unplugged wire, different rods and strange looking sensors — and it is a very clever little puzzle.

We could explain to you how it works (with the Arduino, phototransistors and maybe the source code), but instead we think you’ll enjoy watching [Michael's] video of it.

Now since the present is for geocaching, we’re almost surprised he didn’t include a reverse geocache puzzle in it too!

[Via Reddit]