Ok sogo below and download all the 3D files that we need. They were all printed with PLA filament. Together with the 3D parts we need 3 bearings, the 608zz. WE need a threaded rod of 8mm, nuts, washers and some M3 screws. As for the electronics, we need a NEMA 17 stepper motor. The one I have is quite big so it should have enough power. To control it we need a driver. The cheap version would be those A4988 drivers. But those are very loud. For silent and smooth movement I always use the TMC2202 drivers. They only cost a few more dollars. To control the driver I will use an Arduino NANO and to receive data from the smartphone I will use a Bluetooth module, the HC-05 or 06. To supply everything I will use a 12V DC adaptor connected to a power jack. And that’s pretty much all we need so let’s start assembling this motorized curtain controller.