The Problem

Motorized curtains are becoming increasingly popular, but most commercial products suffer from several limitations:

  • Expensive
  • Closed-source firmware
  • Vendor lock-in
  • Difficult to repair
  • Require proprietary curtain tracks
  • Limited customization
  • Difficult to integrate into DIY smart homes

Many people already own perfectly good curtains and rails—they simply need an inexpensive way to automate them.

verhoBot was created to solve exactly that problem.

The Solution

verhoBot attaches directly to existing curtains using a tiny geared DC motor and custom mechanical transmission.

The robot can:

  • Open curtains automatically
  • Close curtains automatically
  • Operate manually through a mobile device
  • Schedule opening and closing
  • Detect end positions
  • Recharge through USB-C
  • Run for months on battery power
  • Integrate into existing smart home ecosystems

Because the entire design is open source, every component can be repaired, upgraded, or redesigned.

Features

  • Tiny form factor
  • USB-C rechargeable battery
  • ESP32-C3 wireless controller
  • Wi-Fi connectivity
  • Bluetooth Low Energy
  • OTA firmware updates
  • Low power deep sleep mode
  • Automatic end-stop detection
  • Manual push-button operation
  • Fully 3D printable
  • Open hardware
  • Open firmware
  • Beginner-friendly assembly
  • Modular electronics
  • Low-cost BOM

How It Works

The robot uses an ESP32-C3 microcontroller to control a small N20 geared DC motor.

The motor drives the curtain using a compact gearbox and pulley system.

Hall-effect sensors detect the motor position while end-stop sensors determine when the curtain is fully open or closed.

A rechargeable LiPo battery powers the system, and USB-C charging keeps maintenance simple.

Wireless communication allows the robot to be controlled from:

  • Smartphone
  • Home Assistant
  • MQTT
  • Web interface
  • Bluetooth
  • Future Matter support

The firmware is designed with low-power operation in mind, allowing the controller to spend most of its time in deep sleep until movement is required.

Why Open Source?

Most smart curtain products hide their hardware and firmware.

verhoBot takes the opposite approach.

Everything is available:

  • CAD files
  • PCB design
  • KiCad source
  • Firmware
  • BOM
  • Assembly guide
  • STL files
  • Documentation

This allows anyone to:

  • Build one
  • Learn from it
  • Improve it
  • Fork it
  • Adapt it to different curtain systems
  • Use it in research or education

Hardware

Current hardware includes:

  • ESP32-C3 SuperMini
  • N20 6V metal gear motor
  • USB-C LiPo charging circuit
  • LiPo battery
  • Hall-effect sensors
  • End-stop switches
  • Custom PCB
  • 3D printed enclosure

Software

Firmware is written using the Arduino framework.

Current capabilities include:

  • Wi-Fi provisioning
  • Bluetooth communication
  • OTA updates
  • Motor control
  • Deep sleep
  • Position tracking
  • Scheduled automation
  • Safety timeout protection

Future firmware versions will include:

  • Matter support
  • Thread networking
  • Adaptive motor current monitoring
  • Automatic calibration
  • Cloud-free setup
  • Voice assistant integration

Applications

verhoBot can be used in:

  • Smart homes
  • Apartments
  • Offices
  • Accessibility projects
  • Elderly assistance
  • Energy-saving automation
  • Education
  • Robotics learning
  • DIY home automation

Current Status

Development is active.

Current work focuses on:

  • Version 2 electronics
  • Custom PCB
  • Improved battery management
  • Smaller mechanical design
  • Easier assembly
  • Enhanced firmware architecture

Version 1 remains available as a stable reference design while Version 2 explores new hardware and software improvements.

Open Source Philosophy

This project is released to encourage collaboration within the maker community.

Whether you're interested in embedded systems, mechanical design, PCB development, firmware, or home automation, contributions are welcome. Every improvement—large or small—helps make smart...

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