Chengelog:

v3 - Arduino code rework with webpage settings

v2 - second release

• changed motor driver to 12V+ for bigger torque
• added external case with screw for tension adjustment

v1 - first release

• cabuu remix

Summary

This is my remix of cabuu's Automatic blinds automation (thanks!). Reworked for Wemos D1 Mini and European blinds (in the Czech Republic we use different chain type). This type of blinds have only one chain for both functions (tilt and raise). Short rotation will tilt blinds and long rotation will raise blinds. The position of controller was changed due to the limited space next to the window. It allowed me to add stop switch for precise calibration. I am using 12V power source.

This automatic blinds control needs infinite straight chain (without chain connector). So you have to remove connector, remove ~5 balls from each end of chain, made a knot and seal it with super glue. Glued knot is roughly as large as the chain ball. If you have spare chain from some old blinds, you can even extend existing chain with it. Motor Driver (TB6612) is suitable for 9-15V power source.

High torque motor (in my case 35 RPM) can lift heavy metal blinds for small price (big window takes ~45 seconds). Wemos is connected to wifi network and can be controlled over HTTP requests. Buttons was removed (only HTTP remote control is supported for now).

Software

Simple Arduino code attached. DHCP client is enabled, edit wifi SSID and key. Commands available (for IFTTT or other home automation system):
http://IP_ADDRESS/up (fully up, timer is used, needs to be tweaked in code)
http://IP_ADDRESS/down (fully down until stop switch is reached)
http://IP_ADDRESS/open (fully down until stop switch is reached and rotate blinds to open position)
http://IP_ADDRESS/close (fully down until stop switch is reached and rotate blinds to close position)
http://IP_ADDRESS (some status information)

Shop list:

12V motor driver:
https://www.aliexpress.com/item/32907922595.html

Motor (~35RPM for heavy blinds):
https://www.banggood.com/DC-12V-356065110220rpm-Worm-Gear-Box-Reduction-Motor-p-1197020.html?p=KF2715792233201409DJ&ID=47606&cur_warehouse=CN
or
https://www.aliexpress.com/item/33036140291.html
(6 mm shaft without hole is needed)

Wemos D1 Mini:
https://www.banggood.com/Wemos-D1-Mini-V3_0_0-WIFI-Internet-Of-Things-Development-Board-Based-ESP8266-4MB-p-1264245.html?rmmds=search

Power shield for Wemos:
https://www.banggood.com/WeMos-DC-Power-Shield-V1_0_0-For-WeMos-D1-Mini-p-1160039.html?rmmds=search&cur_warehouse=CN

Stop switch (KW12-3):
https://www.banggood.com/10Pcs-Micro-Limit-Switch-Roller-Lever-5A-125V-Open-Close-Switch-p-945733.html?rmmds=search

One ~47k resistor for stop switch (in switch's close state Wemos wouldn't boot without it):
https://www.banggood.com/300Pcs-1-14W-Metal-Film-Resistor-Resistance-30-Values-Assortment-Kit-p-1091920.html?rmmds=search
Try to find smaller pack :-)