A Renter-Safe Smart Curtain Solution

Installing a smart home system allows homeowners to turn off unused lighting, automate temperature schedules, remotely unlock doors for guests, and much more. However, things are more complicated when the home is occupied by a renter. Drilling holes in the walls and permanently installing hardware may not be an option in these cases.

Home automation enthusiast Rooster Robotics ran into this problem when he wanted to install automated curtains in his rental home. There are a number of commercial options available, but none of them could easily interface with his existing curtains and be removed at a later date without causing damage. Rather than give up, Rooster Robotics decided to build his own solution from scratch.

The first prototype used a geared DC motor connected directly to a custom gear wheel, along with an ESP32 microcontroller development board and a motor driver to control movement. Although the curtains could be opened and closed automatically, the system relied entirely on timing. Small variations in motor performance, friction, or curtain resistance caused the stopping position to drift over time, making the setup unreliable for daily use.

To solve these issues, a new version was created with several major improvements. Rooster Robotics redesigned the drive mechanism using custom 3D-printed nylon bevel gears arranged in a 90-degree configuration. This allowed the motor to sit parallel to the wall, dramatically reducing the device’s bulk and making it look more discreet once installed.

A sensing system was also included to monitor curtain position. A Hall effect sensor paired with magnets attached to the curtain wheel provided position feedback, allowing the ESP32 to track movement far more accurately than before. After discovering that the original motor lacked sufficient power, the creator used a bathroom scale to measure the pulling force required to move the curtains so a properly sized motor could be selected.

The system was working much better with these upgrades, but there was still room for improvement. The Hall effect sensor was replaced with an AS5600 absolute angle sensor capable of detecting 4,096 positions per revolution, enabling extremely precise curtain positioning. A custom PCB consolidated the electronics into a compact package, and a dedicated Wi-Fi patch antenna ensured reliable connectivity despite the surrounding metal hardware.

Rooster Robotics also designed a removable sliding rail mount with locking clips so the unit could be detached without tools when moving out of the rental property. The finished device integrates locally with Home Assistant, allowing the curtains to automatically open at sunrise, close at sunset, or respond to room temperature conditions. After three months of continuous operation, the system had reportedly achieved the creator’s goal of being a reliable “set and forget” smart home appliance.