Solar Tracker single axis

Single axis Solar tracking system.

Pre-requisites:
If you are to do this project you need to have some little skills in electronic, soldering (and the solder-iron of course) and to know a bit of arduino so to flash any code adapted from what can be found over internet or the code below.

The project is not difficult but also not straight. See the post printing steps for assembling

This is a complement to https://www.thingiverse.com/thing:5190383



BoM:
Servo SG90 prefer Metal Gear with various horns (one should be long enough around 3cm ; metal preferrably to resist very strong winds)
Arduino
Cable PRO MINI Module Atmega328, Arduino Compatible 5 V 16Mhz
2 x LDR
2 x 10 Kohm
cables
3 pin head for connecting the servo cable connector

1 x Solar panel 12W see link https://www.thingiverse.com/thing:5190383

Max current consumption idle around 14mA
Max with Servos actualising 80mA (5 seconds every minutes in my programme and if necessary)

The solar panel wil