Ropener — Open-Source Smart Curtain Opener (ESPHome / Home Assistant)

The Ropener is an open-source motorized curtain opener that retrofits onto your existing curtain rod. Silent stepper motor, ESPHome-native firmware, no cloud, no app required. Works with nearly all curtain types.

WHAT IT DOES

Pulls your curtains open and closed on command from Home Assistant, Apple Home, Google Home, or Alexa (via Matterbridge). Two physical buttons on the unit for manual control. Stall detection via the TMC2209 driver — no end-stop switches to mount or align.

WHAT'S INCLUDED IN THIS DOWNLOAD

• All 3D-printable parts (STL + STEP)

• BOM with sourcing links for non-printed parts

• Assembly instructions (PDF)

• Recommended print settings per part

• Link to firmware repo and PCB design files on GitHub

WHAT YOU NEED TO BUILD ONE YOURSELF

• ~150g of PLA or PETG filament

• Custom VAL3000 PCB (ESP32 + TMC2209)

• NEMA 17 stepper motor

• Bearings, screws, nuts, etc. (full BOM included)

• A #1 Phillips screwdriver and 1.5mm hex wrench

• About 1–2 hours of assembly time

DESIGN NOTES

The motor housing prints without supports if oriented as shown in the included build plate file. Print at 0.3mm layer height for fastest printing. Curtain hooks clip directly to the printed carriages.

OPEN SOURCE

Everything you need is in this download plus the linked GitHub repo: hardware (STEP), firmware (ESPHome YAML), PCB (KiCad), and assembly docs. Fork it, modify it, build your own.

A FAIR DISCLOSURE

I designed the Ropener for my own house and ended up productizing it. I sell an assembled kit on my website valarsystems.com — PCB, motor, hardware, and printed parts ready to go — for people who'd rather skip sourcing and printing. Buying the kit isn't required; it's just the convenience path. The open-source release is the default. Everything here works standalone.

If you build one, I'd love to see photos and hear what curtain rod you used. Drop a Make on this listing or open a discussion on GitHub.

— Daniel

Edits:
7/3/2026: Updated to v1.1. Updated the drive gear to smaller diameter, increased torque by 30%.

7/29/2026: Updated to v1.2.1. Fixed a couple minor mistakes and decreased wall thickness on main body.