Update: Code added as an *.ino file
My first moving thing. I'ts still ongoing. I created it as an experiment to see how effecient i could make it. The plan beeing is to make it self sufficient. So far i have failed to locate a rechargeable powersource around 5 volts that is small enough to make this a challenge.
It's an easy build containing:
2x 9g servos
1x Arduino Nano
4x 91 Ohm resistors
1x Soldering lab board
4x Light sensitive resistors
All the pieces are easy to find online. If you need the code (fairly basic so far) it's in the files section. I included the CATparts if you want to scale this to fit other solarpanels and/or lab boards. It will probably work in any scale. Using steppers probably works just as good if you change the code an build a stepper driver..
Print the parts, screw the servos in place. I glued the solar panel in place and i did glue the "servo heads"(?) in the slots on their repective pieces.
I also glued the light sensitive resistors in their places.
"Sun resistors" creates a voltage divider between an anlog port and 5 volts and are coupled to ground using the other resistors.
To follow the sun simply write a program that compares the voltages in each plane and moves the servos to minimize the difference.
That is about as far as i have taken this right now. I also added code to prevent the panel to move i low light condition by messuring the avrage light over all four sensors and limiting movement over a specific value. Oh and i added som variables to find tune speed, position and so on...