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    Breaking it Down


    It's entirely possible that, you already know what geocaching is and what it means. Great! You can probably skip this article, and move onto finding an element14 trackable and contributing to the Atlas of Scientific Achievement!


    If you do not, created this nice and short introductory video:



    For a lot of people, geocaching will be a new term and idea. It’s probably best if we break up the word ‘geocaching’ into its two components: the first being ‘geo’ short for ‘geo-location’ and the second being ‘caching’ meaning hiding something in a secret place.


    'Geo-location' is the process of identifying the physical location something by means of digital information. In the case of ‘geocaching’ this typically means a Global Position System (GPS) is used to acquire longitude, latitude and altitude co-ordinates; like using an in-car guidance system or ‘satnav’ (satellite navigation).


    'Caching' or 'cache' is a collection of items stored in a hidden (or potentially difficult to access) place for future use. Geocaches are put in place and maintained voluntarily by individuals. Thus, Geocaching is the process of finding items stored or hidden (geocaches) by the use of a device that uses digital information -- and hopefully enjoying the journey and challenge along the way.


    A Brief History


    The hobby of Geocaching has been around for a very long time but was typically restricted to people with access to expensive GPS devices, this functionality is now easily accessible in devices and accessories from cars, smartphones and other affordable consumer electronics. Now anyone, with the aid of portable internet access, can use latitude and longitude co-ordinates with the site to find caches with the help of clues and hints provided by the person whom hid the cache, in parks, on hiking trails and mountain tops.


    Websites such as exist to give people a place to post information about caches they have hidden and for others to share when they have found that cache, but anyone can hide a geocache, anywhere. Geocaching really hit the mainstream when it was used as a part of the marketing support for the the 2001 film “Planet of the Apes”. Geocaches were created internationally that contained props, tickets and other items related to the film. These caches were promoted on the website and some of these caches are still maintained by people unrelated to the original marketing.


    What do I use to Geocache?



    You do not need a dedicated GPS device (such as the one pictured). If you have a smartphone with access to Google Maps or the app then it is possible to have an up to date satellite map to help navigate and direct you to where you are going in real-time.


    Or, you could build your own.


    With the use of a GPS add-on for a Devkit or Single Board Computer it would be possible to develop an electronics project to use to Geocache. This requires the use of complex mathematics to calculate the distance to the destination from where you are and take into account factors such as the curvature of the Earth, all based upon the GPS co-ordinates of where you are and where you are going to.


    Depending on the capabilities of the hardware you choose, you could create a solution that provides simple feedback like an LED (light emitting diode) that flashes more quickly the closer you get to the target.  Or you could hook up an LCD (liquid crystal display) and display anything from text to a fully graphical map with the target and your current position. A lot would depend on the hardware’s processing power, storage, internet connectivity and the software's ability to update.


    It should also be noted that GPS devices of a consumer grade are typically inaccurate in certain conditions and, depending on how many satellites it locks onto, can have an inaccuracy of a few feet/metres to 15 metres. This is why devices such as smart phones suggest to enable WiFi to aid in triangulation and assist in geo-location, and why some also have barometers for elevation.

    II have taken apart my own SatNav to give you a peek inside. You cannot see much of the inner workings due to the shielding in place to prevent electromagnetic interference, likely so that it can maintain safety standards. I would have taken these off but I still use the SatNav and did not want to damage it.

    Devices like this were likely made with a prototype first, potentially with a development kit before having the custom printed circuit board (PCB) designed and made, with the surface mount components put in place in mass production. You can see some parts of the PCB where there's space for functionality on 'higher end' models, likely a 2.4Ghz on PCB antenna.


    {gallery} Inside a Vehicular SatNav


    Garmin SatNav: The resistive touchscreen with its matt finish, let's crack it open


    Behind the Screen: We can see the battery, speaker and circuitry, mostly shielded from EMF


    On the Reverse: microSD storage, USB port and GPS Antenna with shielded circuitry.

    You can of course prototype and make your own GPS/Geocaching device out of a Raspberry Pi and add-ons. Sign up to win one of 10 Raspberry Pi 2 GPS Kits!


    What is in a Geocache?

    A geocache can range in size form not much larger than a one pence or penny to virtually any size that is practical. Each usually contains a piece of paper where the "finders" can log their name, date and the time that they found the cache.


    Some caches have personal artifacts that people have made or bought, with a take one/leave one honor system. That is, if you take something from the box then you're expected to leave something behind.


    There are also trackables that might be found in the cache. These are promotional items with a uniquely identifiable code. The idea with trackables is to move them along on a journey and to log its movement by logging onto and use the unique code ID.


    It used to be the case that a cache was also ‘get to this location and be captured on a webcam’ but this concept has since been deprecated. Still, finding a geocache is as much about bragging rights and the goodies inside as it is about the scenic journey and puzzle of travelling to and finding it!


    How do I find a Geocache?

    Once you have your GPS receiver, you need to know where a geocache is so you can find it. There are many websites that list GPS co-ordinates of maintained geocaches. If you're new to this, you'll probably be surprised to find some near you, wherever you go.


    Having the GPS co-ordinates is just the beginning of finding the cache. Once you arrive at the destination you still need to find the cache. Very few are out in plain sight and even if they are, they may not be large enough to stand out. Remember also that, depending on location and the type of GPS receiver you're using, your actual location may be off by inches, feet, or meters.


    This is why cache listings also have clues or hints, cryptically stated in the form of a rhyme or riddle, or just encrypted with a very simple cipher so as to not directly give the game away as to where the cache might be.


    In the situation of very small caches they could be magnetically attached to somewhere out of sight; or in the case of larger caches they may be easier to spot and so the clues may not be necessary.


    What About Trackables?


    Part of the treasure hunt of Geocaching can be with trackables! These are uniquely identifiable items that can have various purposes and are often themed. People find them in geocaches, record their find on and help them on their merry way. Sometimes they're heading to another location, or trying to go for a distance, others just try to see how many people can interact with a trackable!


    As part of Engineering a Connected World, the element14 Community have 1,500 trackables which we have designed to be like Circuit Boards and we have put together an Atlas of Scientific Achievement with the goal of seeing how many we can get across the globe to visit geocaches near landmarks of Engineering and Scientific interest.