I'd like to build an autonomous remote wind station + camera that I can install near my favorite kitesurfing spot so that I can
- Know in "real-time" both speed and direction of the wind
- See what's going on there (it's mainly to know whether the spot is crowded)
As I have little knowledge of electrical engineering, I'm asking here for some help designing this remote station.
Here is what I've come up with
Objectives
- Learn - I'm doing this to learn new things
- Cheap - I do not exactly have a budget, but price will be an important factor
- Autonomous - It has to work 365/24 without human intervention
Main subjects
- Microcontroller
- Communication
- Power
- Sensors (camera, wind speed, wind direction)
Microcontroller
It has to be programmable, so I can update/improve the behavior of the station if needed.
Any programming language will do - I'm a software engineer, that's what I do
I was thinking something like the Arduino, but I have no idea which model is the best fit for this station.
Communication
As the spot is 50km away from my home, I've found that the only communication protocol/network usable is GPRS/GSM (please, correct me if I'm wrong).
Sending the values read from the sensors (wind speed + direction) can easily fit in a SMS.
I've found a SMS gateway that let me receive SMS for free. It appears to be exactly what I need.
But sending an image (even a 320x240) every minutes (or less) requires a data connection. Indeed, transferring 320x240 = 76 800 pixels will take about 590 SMS (at 140 bytes per SMS minus 10 bytes for the overhead).
Again, there's way too much choice here. Do I need a dualband, a quadband or a 3G/GPRS shield?
Note: I like the 3G/GPRS one as I can easily attach a 7 € camera. But 140 € is kind of expensive.
Note II: I am aware that using GPRS/GSM/3G requires a SIM card with unlimited SMS and/or data. But in France, they are pretty cheap (~15€ per month)
Power
Solar powered appears to be the best (only) choice.
This solar module looks like what I need but I have no idea if that is too much or not enough?
- Is there any way it can be cheaper?
- Have you got any advice regarding the installation of the solar panel in order to maximize its efficiency?
- Is there any warnings regarding the rain?
Sensors
Camera
Apart from the cheap camera (which goes with the 3G/GPRS shield), there are plenty of cameras available.
Again, way too much choice here. I don't even know where to begin... What do I have to consider?
Wind Speed + Direction
I've found these weather meters and even a tutorial (in French) with some help regarding how to connect the sensors to the board and read both values.
There is also some code for Arduino.
This appears to be the easiest part (at least for me) of the station.
Reading values from the Wind Speed sensor is as easy as incrementing a counter and reading values from the Wind Direction sensor is as easy as doing a modulo.
Some other questions
- How do I prevent the station from being struck by a lightning?
- What is the best material to use for the support? Wood? Steel?
- What kind of enclosure can I use to prevent the station to heat too much?
Thanks