Adding step 4 PCB installation

README.md

@@ -69,7 +69,7 @@ The goal was to make a circuit quickly to develop the program with ESPhome and c
 
 The aim now was to install the main components (limit switch, photoelectric sensor, etc...) and connect them as shown in the circuit above.
 
-![prototype_wired](.assets/images/prototype_wired.png)
+![Prototype wired image](.assets/images/prototype_wired.png)
 
 I let this prototype run for several months to see what needed to be improved, modified or removed, both physically and in the program.
 
@@ -84,7 +84,19 @@ For the program I was able to make and to optimize a few things:
 - A short delay was introduced to first provide a warning light and then activate gate movement.
 - ...
 
+### Step 4: Design, manufacture and installation of a new PCB
 
+After correcting the main problems with the circuit and electronics in general, I set about designing an electrical board to make the portal's operation more reliable and, above all, more professional.
+
+You can have a look at the PCB documentation: [LiHoCo Yard gate PCB v1.0](hardware/PCB)
+
+Once the electronic board was soldered and functional, I removed the prototype and installed the new PCB :
+
+![Empty box image](.assets/images/empty_box_after_prototype.png)
+
+Then I installed the new PCB and here it is! #BrandNew
+
+![PCB Wired image](.assets/images/pcb_wired.png)
 
 ## Points of improvement