Hello Edio,
Welcome to DIY paradise.
- 2 LDR in North/South Axis and 2 LDR in East/West Axis.
Most solar trackers do not use N/S axis, since this can be done manually every 2 or 3 months.
Saving about 50% on hardware and complexity. This is a quick and simple adjustment on a
polar mount.
The tilted 'hinge' of a polar mount is simple to setup and can be very accurate in tracking the sun, from horizon to horizon.
- An Operational Amplifier Circuit to compare the results of the 2 axis.
It might be better to use a Comparator chip that has a TTL or other output that are compatible with your motor drive circuit.
And, most Comparator chips use a single power supply vs. many OpAmps using dual PS + & - 15v etc.
- A L297/L298 to drive the stepper motors.
- 2 Stepper Motors, to guide the structure to follow the sun.
- A simple and slight structure, to avoid work to the motors.
These drivers and motors seem like low powered devices.
You might want to start off with the goal of a
Self-Powered tracker.
Meaning you want to track the sun with a PV panel that has
enough power output, to run the motors and controller circuits.
Also With enough rechargeable battery power to re-turn the tracker to the
east (Home posistion) at the end of the day. (So it's ready for sunrise).
This takes some careful design work. Don't want it going 'Home',
if the sky gets a bit dark in the middle of the day.
Your design should start off with the size & weight factors of the PV panel.
Once the PV is selected, the size and power of the other components can be selected,
Based on their capability to handle the PV panel.
Sounds like a fun project..
Good Luck,
Rich