Hi ! 
I'm doing a senior project now. It's about solar cell I did it 2 axis by using 2 servo x-axis and y-axis before I post this topic I used to use light-to-voltage converter for finding the most light intensity but it's not work so my supervisor told us using solar cell as sensor by using itself read voltage and send it to arduino for controlling solar tracker that it can move by servo. I have no idea how servo knows the position when sensor read or it works seperate?
PsdL:
I have no idea how servo knows the position when sensor read or it works seperate?
The Arduino knows how to position the servos. The Arduino can read the voltage from the solar cell. Your sketch is responsible to read the solar cell and position the servos to get the maximum voltage from the solar cell..
do you have any example code ?
Look in File->Examples->Servo->Sweep for an example of how to sweep a servo. That is about 90% of your code. Sweep each servo and look for the angle that produces the highest input. Move to that position. Repeat every four minutes: the time it takes for the sun to move about 1 degree East-West.
Thank you, johnwasser.
Do you know about wiring solar paner to arduino? I'll make it's as sensor which pin on arduino I have to use and my solar panel has 17.5 max voltage.
You don't really need to connect the solar panel to the Arduino. You can just use a photoresistor.
Thank you for your suggestion, Isaac96.
But my colleague would like to make it different that's why my supervisor told us using solar cell as sensor. Have you ever seen the project's like this?
Can solar cell connect to arduino uno directly?
If you are going to connect the solar cell to the Arduino, use a voltage divider.
I'm surprised you can get more than a few volts from a solar panel small enough to be moved by a hobby servo.
For safety you can divide the voltage by 4 so the Arduino can go up to 20V (4x5V). To do that use four 1K resistors in series between the plus and minus terminals of the solar panel. Connect Arduino Ground to the minus side of the solar panel. Connect your choice of Analog Input pins to the other side of the resistor connected to the minus side of the solar panel (the first of the four resistors).
Where did you get this solar panel capable of 17.5v that is still small enough to move with servos? I'm pretty sure I need these
Hi,
The 17.5V will be the open circuit voltage of a 12V panel.
As for the servo bit, the PV will have to be more than 12W to get at least 1A in good laboratory standard sunlight.
Isaac, can you post a diagram of how you envisage connecting everything, you will need a battery to charge off the PV and some sort of charge controller as well.
Tom.....
Look at the "knob" servo example in the arduino examples. You might use "solar tracker" in the search box in the upper right of this page to find similar solar panel projects. Are you wanting to use a small solar cell to actor as a sun locating sensor to be used to aim a large solar panel?