Goals!

Alright, so now its time to dig in to what I want to do with this project!

Basically, my ultimate goal is to affordably replicate the basic functionality of the official automated airport weather stations.  Doing this will allow me to have observational data for my exact location at a higher temporal resolution (airport sites typically only report a few times per hour at most; I would like to have 1-minute observations).  Furthermore, by developing a low-cost system, the station could be more easily adopted to provide better spatial resolution for surface observations, to create a mesonet, or even to build portable observation pods.

Here is some information on airport weather stations.  Most of the sites are designated as AWOS or ASOS.  These sites are run by the National Weather Service, the Federal Aviation Administration, and the Department of Defense.

ASOS Site

Here is a breakdown of the different parameters that I would like my station to measure (in order of importance):

1. Temperature
2. Barometric Pressure
3. Humidity
4. Wind Speed
5. Wind Direction
6. Precipitation
7. Lightning
8. Soil Temperature
9. Soil Moisture
10. Solar Radiation
11. Photography (webcam or still-shots)

There are a few other considerations that I will try to work into my station:

1. Battery power
2. Solar power
3. Real-time clock
4. Portability
5. Long-term data logging
6. Data relay via internet
7. Data relay via cellular connection
8. Data relay via radio (APRS)

Who am I?

Okay, I'll keep this post short because you guys probably aren't too concerned with getting to know me, but I think having a little bit of background on what I know and where I'm from would be good.

I am studying meteorology at the University of Nebraska-Lincoln and I am in my senior year.  I have some programming experience, but I haven't done any extensive embedded systems programming. Therefore, I will be relying heavily on information and code from others and modifying it to serve my purpose.

Since I promised to keep this short, I won't add any more personal information.  If you want to know more, follow me on Twitter @aaronmangels, comment below, or send me a message.

Me with our new dog Cooper.

What is the Raspberry Pi and why did I use it?

I've never heard of Raspberry Pi...What is it?

For those of you who are unfamiliar with the Raspberry Pi, it is a credit card sized, Linux computer that was designed by the Raspberry Pi Foundation in the UK.  This nonprofit foundation designed it in an effort to get schoolchildren interested in computers and programming.  They initially released a batch of 10,000 "Model B"boards for $35 apiece, and they quickly (within an hour) sold out.  Since then, they have been able to maintain a steady supply of boards and have released a "Revision 2" and a cheaper "Model A" version for $25 (their original pricing goal).

Okay, Cool! So what can it do?

At the heart of the Raspberry Pi is a 700 mHz ARM11 processor.  The foundation describes it to be roughly equivalent to an old 300 mHz Pentium II processor, but with much better graphics.  Because of the Broadcom GPU that is included on the board, the Pi can decode 1080p video and is about graphically equivalent to the original Xbox.  Also, the Model B board includes 512 mb of RAM along with 2 USB ports, an ethernet port, HDMI and composite video ports, and a header of GPIO (General-Purpose Input/Output) pins.  (The Model A has 256 mb of RAM, 1 USB port, and no ethernet.)  

Why did you decide to use it?

Getting a full-featured computer at such a low price and small form factor just seemed too good to pass up, so I quickly snatched up on of the Model B Revision 1 boards.  I thought initially I could make a set-top box for media streaming/viewing, but the lack of Netflix support killed that idea.  I didn't do much with it for a few months, but then I realized that it would lend itself well to a homebuilt weather station.

The ARM11 processor is more than fast enough, and it consumes very little power (~2W) so I could possibly run it off of battery/solar power.  The GPIO pins allow me to interface directly with almost any sensor you can think of.  Essentially, the Pi is giving you most of the same interfaces as an Arduino for the same price, but the Pi is an complete computer while the Arduino isn't.  With such huge interest in the Pi, there is already a large and expanding user base to test and write code for the different sensors I will be using.  Most importantly, its cheap! So when I screw up, I don't have to break the bank to replace the system.

Raspberry Pi (Model A)

Here's a picture of my Model A that I just got.  (My Model B is busy at the moment)

If you want to learn more about the Raspberry Pi, visit the foundation's website at raspberrypi.org.  

First Post!

Hello, my name is Aaron Mangels and welcome to my (first ever) blog.  

If the title of my isn't obvious enough, I will be building a weather station based around the Raspberry Pi.  I already have been tinkering with it for several months, but now I'm finally able to devote enough time to the project to actually go somewhere with it (and blog the process). 

Thanks for reading, and hopefully you will find it useful and interesting!