I’ve been working on a project to detect the opening angle of my garage door using an HC-SR04 ultrasonic sensor. It’s been a fun challenge, and I wanted to share my progress and thoughts with the community.
Initially, I set up an automation in Home Assistant to track the garage door’s status using its built-in end switches. This worked well for basic open/close detection, but I wanted more granular control—specifically, knowing the exact percentage of how open the door was. That’s where the ultrasonic sensor came into play.
The idea is to mount the sensor on the garage door’s track and measure the distance to the moving part of the door. As the door opens, the distance increases, and as it closes, the distance decreases. By correlating these measurements with time, I can calculate the opening percentage. For example, if the door takes 12 seconds to fully open, each second corresponds to roughly 8.3% of the opening angle.
I’ve also considered potential issues, like the door stopping midway. In such cases, the sensor would still provide an accurate reading of the current position, which is crucial for maintaining reliable automation.
To implement this, I designed a custom mounting bracket using a 3D printer to ensure a secure fit. The sensor is connected to an ESP8266 module, which communicates with Home Assistant via MQTT. This setup allows for real-time updates and integration with existing automations.
I’m curious to hear if anyone else has tackled a similar project or has advice on improving the accuracy or reliability of the sensor readings. The HC-SR04’s ability to measure up to 5 meters gives me confidence, but I’d love to know if there are any pitfalls or optimizations I should be aware of.
Overall, this project has been a great learning experience, and I’m excited to see how it can enhance my home automation setup. If anyone has questions or suggestions, please feel free to reach out!