hello everyone, I created a BRACHIOGRAPH with a raspberry pi 3 and a three servo here is the documentation https://www.brachiograph.art/ and also here is the github link of the project https://github.com/evildmp /BrachioGraph.git , I noticed that it draws me every time a half circle, so I tried to test the GPIOs of the raspberry pi with the servos I distinguished that the GPIOs do not work except GPIO 14 it's the only one that works can you help me
colporteur has mentioned the reliability concern too. It can't be overstressed how the prototyping needs to change significantly. It's not surprising that things do not work because you have several points of failure on each connection, due to the way you're connecting and chaining things with unreliable items and techniques.
If you really want to continue with breadboard then at least replace it. The one you have is so worn out on the outside, that the chances that all the connections inside it are fine is probably close to zero percent. We are talking from many years of experience. The one in the photo below is low-cost, but should work well. Any cheaper will likely not be very good.
The round-moulded jumper wires you're using are extremely bad. These types are much better (but buy from a good place, because the cheapest ones are sometimes cut inside near the metal crimp, but on the outside look fine).
Replace the breadboard with soldering. Use pin headers (shown highlighted in red. Here is an example). They will connect to your servos and to the jumper wires to the Pi.
Underside of the board can look like this:
or like this:
The photo above is from here: Circuit Prototyping
These are all solid reliable connections that are tested with a multimeter if you're unsure.
