Electric Curtain
I started its design in 2019, however back then I didn't have a 3D printer and my parts which I got printed from outside would constantly break due to design flaws. In 2020 when I finally got my own printer I decided to complete this built. It can open the curtain in about 1 and a half mins and close the curtain in 1 min. It's completely integrated with Alexa now and works closely with the sunrise and sunset times as well when my alarm gets dismissed.
Insights and coding.
On the exterior, there is a 3D printed wheel that locks with the chain of my roman blind. This wheel is rotated by a high-torque 12v (40rpm) motor which is used in my cat feeder too. The motor gets its power through an l293D motor driver which is controlled by a Node MCU which gives it Alexa capabilities. There are 2 power supplies, one for the Node MCU and one for the Motor itself. This design has been working amazingly for me for the past year now. It's secured on the wall with a 3D bracket.
The code just controls 2 pins on the Node MCU so that it can rotate the motor multi-directionally. This code more or else remains the same while using Sinric pro.