Say Hello to the Coobro Geo
The Coobro Geo is a project that started off as a way for me to learn more about designing and building Open Source Electronics. First, let me explain what the Coobro Geo is, then after the the jump, I will give a little explanation of the process that I went through to get to where the project is today.
The Coobro Geo is an easy to assemble GPS navigation kit. Upload coordinates, turn it on, and the Coobro Geo will help you navigate to any destination on earth by using LEDs to show you the correct direction and distance remaining. Before you leave on your quest, press and hold the breadcrumbs button and the Coobro Geo will remember your location and help you navigate back. Store up to five pre-entered destination coordinates and five breadcrumbs, or modify the open source code and store as many coordinates as you want.
Use the Coobro Geo to help you find geocaches, store and navigate between hot fishing spots, complete a scavenger hunt, or simply help you find your car after a hike. You can pick up a Coobro Geo of your own here.
The Coobro Geo started as an idea I got after reading about Sean Carney’s Arduino GPS System. I loved the idea of building something like this so I could use it to go geocaching with. I quickly discovered that when you add up the cost of the LCD shield, GPS shield, GPS module, Arduino, and battery pack, my cost was around $200. Yikes. So, I decided to use the components I had and bought only the GPS module, which was $60.
I used a breadboard, some LEDs, and an Arduino to build a really simple navigation system. I quickly wrote up some code, which used a lot of Sean Carney’s code and a bit of help from around the web (as well as Mikal Hart’s TinyGPS library). The GPS module I started with was the Locosys LS20031. This was a great little module as it was possible to use .1″ right angle header pins and use the module with a breadboard. I had three LEDs up front – one for left, right and straight headings. I then had one green LED that would light up when I was within 5m of my destination.
I uploaded the code, wrapped the whole gizmo in a ziplock bag, and set out to find a geocache at 10pm on a March evening…in the middle of a HUGE Minnesota snowstorm (we got nearly 18 inches of snow that night). Not only did the system work with only four LEDs, it was a lot of fun to use. Compared to the $200 GPS device I was using to find geocaches, this prototype got me just as close to the cache, and it did so in the simplest possible way. I knew then that I had to create a more robust version that had more functionality, but the with the same LED only design. It was time to learn how to design a PCB.
I started out my journey to learn how to use Eagle Cad by designing a simple prototyping board for an Arduino Fio. Looking back at the way I designed the board, it is pretty comical how ugly the thing was. I actually used the auto-router to do something as simple as a proto-board. It wasn’t pretty, but I was learning fast. Thankfully, there are a ton of great tutorial videos on Youtube that helped sharpen my Eagle skills. I started learning tricks: the joys of hand routing traces, and the benefits of ground planes. With the help of Adafruit and Sparkfun’s amazing Eagle libraries and open source schematics, I learned the best ways to design my gizmo. I also found another tool that was invaluable. The DorkbotPDX PCB Order that is run by the incredibly awesome Laen. Not only does he offer a way for us hobbyist electronics tinkerers to get our hands on high quality PCBs for cheap, he also answered my numerous Eagle Cad questions. I began pumping out prototypes every couple weeks through his service. Laen offered up advice on how to fix certain things (traces too thin, silkscreen issues, and more), and then took my Eagle .brd file and turned it into a real PCB.
You have no idea how excited I was when my first pretty purple PCB arrived in the mail. Something I had assumed, only months earlier, was impossible for someone like me to create. I quickly soldered in all of the components and flipped it on. Holy crap, it worked, but I quickly found out that there were a lot of problems with my design. I spent the next week tweaking code, and tweaking my Eagle design. I then sent in another PCB order to Laen. This process repeated every month or two for the next 8 months until I got to the design I am at today.
The design is actually pretty close in design to my first prototype. The distance LEDs changed from vertical to horizontal, and I switched to the much better (in my opinion) Fastrax UP501 GPS module, which allowed me to make the board quite a bit smaller.
To say the least, I am forever grateful to the great people who helped me discover this amazing hobby. Only a year ago I was blinking LEDs with an Arduino, and now I am selling a fully functional GPS navigation kit. Isn’t the internet great? What a crazy, and wonderful addiction this has become. This one kit has made it possible to take all of my other ideas and turn them into an actual product. I can’t wait to share them with you all.