SKY CACHE: Mobile Aerial Geocache




Intro: SKY CACHE: Mobile Aerial Geocache

This is my completely autonomous Mobile Aerial Geocache, or MAG. I'll show you how to make one, and participate in this project yourself.

I wanted to create a new kind of interactive cache that would have the ability to travel through the sky, and be tracked in real time with a small GPS device.

My goal is to give the community the ability to track, find, and relaunch this cache to keep it ever wandering

What is Geocaching?

Geocaching is a free real-world outdoor treasure hunt. Players try to locate hidden containers, called geocaches, using a smartphone or GPS and can then share their experiences online. -

I will be updating this Instructable in the near future as this project progresses, and invite all of you to follow along and participate. Please comment with your thoughts, ideas, and knowledge, and lets make this a collaboration!

Step 1: What You'll Need

-a brightly colored "pool noodle"
-a saw or knife
-a hole saw kit
-a stash (not to be confused with Stache)
-a GPS device

Step 2: Make the Container

Cut off a length of noodle. This will be the body of your container.

Next, fit a hole saw bit into the noodle end.
Find the largest one that will fit inside without ruining the container.

Cut off another length of noodle, then cut that piece in half lengthwise.

With your hands, gently and slowly twist the saw into the noodle piece COUNTER-CLOCKWISE.
(otherwise the piece will be torn too roughly) Repeat with other half.

make sure your end pieces fit properly.

Step 3: Add Treasure and Test Lift

I tested lift with 3 helium filled balloons that I bought at Vons (Safeway). They can lift about 20.2 grams of weight. The stash and container weighs in at 14.8 grams. WE HAVE LIFTOFF!

Step 4: GPS Unit and Tracking

My GPS unit is still in route from china. I will update as soon as i get it in. I'm not very familiar with these type of trackers/locators, so if anyone has any useful info, please leave a comment below.

This is, in short, what the ebay description reads:

Real-time location tracking, track playback
Support SMS/ mobile client/computer/Google map and Location service platform tracking
GSM band: 850M/900M/1800/1900M
Standby time: 7 days
There is a 50~500meter error, which based on the existing GSM/GPRS network and GPS signal.
Generally the suburb area has a larger error than Urban.

That's a pretty big error range, but i'm gonna give it a shot anyways. I could always add the "Garmin Chirp" to help better locate the package, but maybe on a future launch.

I plan to package the GPS unit  together with the stash in a larger noodle. I'll probably need about 12 balloons all together.

I'm not sure how the live tracking works exactly, but I will update with more info as soon as I know.

Step 5: Launch and Participation

The Launch date should be within the next 2 weeks if my package arrives on time. STAY TUNED!

What I want to see happen:
-My goal is to give the community the ability to track, find, and relaunch this cache to keep it ever wandering

-I plan on posting the necessary information on different geocaching websites for others to track and locate the Sky Cache, but would like this Instructable to be the main hub of communication, at least for now.

-I would love to see others create their own Sky Caches, and link back to here, and create something organic and ever growing.

My Concerns:

-What happens if the GPS device loses power in mid flight?
  (how can I power the unit while in flight?)

-What happens if the cache lands in the ocean? (could I make a lightweight waterproof container?)
  (If I had an Epilog Zing 16 Laser, I'm sure I could make any number of amazing cases!)

Lets get a discussion started. Help me answer these questions as we wait for launch!



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    31 Discussions


    2 years ago

    I'm pretty sure this is against the geocache guidelines


    4 years ago on Introduction

    I sort of confused, is this a Geocache, or some "cache" you made. Anyways, if it were to be a it coud't be a Geocache. What is it for, what is it!


    5 years ago on Introduction

    Nice try but I'm afraid I think that this would be rubbish as a cache. It is too temporary and misses the point of a cache highlighting it's surroundings. However it might make a very good 'trackable'.


    I just got the GSM tracker in today, and will update shortly. Thanks to everyone who is following along, and giving support / ideas!


    5 years ago on Introduction

    Really cool project - I have always quietly held a desire to find a balloon complete with tag from one of those 'furthest travelled balloon' contests at village fetes etc. This takes that to a new level. How you gettting on?
    My contribution.....
    I notice that orntihologists are tagging birds with tiny geo positoning kit , solar powersed, very lightweight and can be programmed to chirp their position at set intervals.
    No idea of satellite costs etc
    I want to be a part of this movement!!

    1 reply
    American RuinChipfire

    Reply 5 years ago on Introduction

    I just got the GSM tracker in today, and will update shortly. Thanks for the heads up on the positioning kit. I'll definately check it out! Thanks for following along!


    5 years ago

    Hey I want to know if this actually got approved as a Geocache? If so, that opens a whole bunch of possibilities for future design ideas. Great work tho!

    1 reply

    I just got the GSM tracker in today, and will update shortly. I'm going to a few Caching sites, and I think I may have to list it as a cache AFTER it lands... but I'm gonna see what I can do. Thanks for following along!


    5 years ago on Introduction

    For power, you could use a radio-isotope thermal generator... or a solar cell.


    5 years ago on Step 5

    The simplest idea would be to get some solar panels on the device and then you could put the whole thing into low-power mode and send out tweets periodically. Weight would be an issue for something more complicated and you may have to embiggen the balloonage.


    5 years ago on Step 4

    That's not a gps unit you've bought. It's GSM tracker, which explains the error margin. A proper gps tracker with GSM module tends to be quite expensive, and not something I'd bung in a balloon and set off! But it should do the job reasonably well.


    5 years ago

    I think this would be great, but i believe in order for a cache to be posted for the "hunt", a geocache official has to find the cache and verify it first. I haven't checked the website, but you may want to check with before the launch.

    1 reply

    5 years ago

    Great idea!may try to keep the charge on GPS unit with a small solar recharger. But that would make it heavier

    3 replies
    American Ruinjgarton

    Reply 5 years ago on Introduction

    Maybe I could wire a solar panel from one of those walkway nightlights.... I'd just have to Google how to do it....

    eh well those "walkway nightlights" have rather weak solar panels. You might want to check out for a better solar panel with proper stuff


    They work and the walkway lights are probably one of the more cost efficient ways of getting them. Hmmm... seems I may have seen an instructable on the topic.