I’ve been working on this project for around 9 months now and I finally have a satisfactory solution. I was inspired by @jetpuf’s implimentation using the ESP8266.
My solution had to be a bit more creative in order to have low enough power consumption to run on batteries and allow for solar recharging (with a small and discrete solar panel). My solution was to add a central ‘hub’ which is always connected to WiFi which can communicate with the blinds. The blinds are generally ‘sleeping’ and only awake when they receive a command from the hub (over 915Mhz RF). The Hub consists of a WeMos D1 Mini with a RF shield (using RFM69W) and the blind controller uses a Moteino from lowpowerlab.com which also has a RFM69W. The moteino is seated in a custom circuit board that I created which handles the battery, solar charging, servo output and momentary switch input.
Here are the features:
- Fully self-contained (no need to wire in power)
- Able to move to 180 different set points
- Standard “Close” position
- Customizable “Open” position
- Able to manually open/close blinds
- Able to send commands to groups of blinds
- Able to send command to all blinds regardless of group
- Theoretical 8.9 Year battery life on 2200mAh LiPo (~20uA while sleeping)
- Able to charge/top off battery quickly with small solar panel (using 5v 200mA panel)
- Able to report battery voltage/percentage
- Able to report charger status (Charging/Not Charging/Fully Charged/Error)
I am currently selling the custom Moteino shield on Tindie:
Videos:
Pictures:
Base Station:
Solar Panel Installation:
Everything Installed in a Blind:
Bottom of Gear Box (see momentary switch):
Switch showing through original drawstring cutout:
Final Moteino Shield design (populated board and bare PCB):
Earlier prototypes (shows full assembly w/ Moteino):
Reflowing some prototype PCBs:
Reflowing a few Moteinos (I’m using 50% bought and 50% made):
SmartThings Interface:
Single Blind:
Group of Blinds:
Base Station:
Code:
3D Printed Parts:
Parts List
1x WeMos D1 Mini
1x Moteino
1x Custom Moteino Shield
1x MG946R Servo
1x 5v 200mA solar panel
1x 2200 mAh LiPo battery
1x 3D Printed Gear Box
1x 3D Printed Gear set (2x gears)
1x 3D Printed Circuit Board Cover (inside of blind is sheet metal)
1x 3D Printed Solar Panel Case
1x 3D Printed Base Station Case
Special thanks to @jetpuf for allowing me to use and modify his gear box design and to the LowPowerLabs community for helping me with Moteino coding questions!