Sensing the Light…
Recently, I posted about using a solar panel as a method for charging a battery that powers the Arduino. Although using a solar cell as a power source is the most obvious use, it is not the only use!
I found a post over at little-scale that shows how to use a solar cell with an Arduino as a photo sensor. The code looks very similar to reading a pot, or other such device on an analog input. Although, there a few caveats to doing this noted by little-scale: The solar panel used in this example was rated at 2V and 25mA.
• Do not use a solar panel rated in excess of 5V. Doing so may damage the Arduino
• If data values appear incorrect, try scaling the byte ‘data’ in the Arduino sketch as it is captured. The analog inputs read data at 10 bit. However, a single, serially-printed value can only hold 8 bits of information.
• The data range with this particular solar panel is 0 < 6 using power-efficient, indoor lighting at night.
The next question after HOW could be WHY? There a many different applications that spring to my mind, from practical to abstract. I am also curious if you could still use a panel as a sensor and power source, by having one trace going to the analog input, and another going to the power source.
I have also decided to include a few examples from practical to abstract, to get your thoughts flowing on this subject. The first example is a “practical” one from youtube user, ringsofdeath. The second is a more “abstract” one from youtube user, 5imian. I hope you enjoy the videos and they get the juices flowing!
- Read the blog post at Little-Scale on “solar sensing”
http://little-scale.blogspot.com/2008/03/connecting-solar-panel-to-arduino.html
- View a “practical” example of solar sensing on YouTube
http://www.youtube.com/watch?v=oThoa_zHTkk&NR=1
- View an “abstract” example of solar sensing on YouTube