I’ve been exploring innovative ways to detect human presence in my home without relying on traditional motion sensors or phone Wi-Fi. After some research, I stumbled upon an interesting idea: using humidity variations to infer when someone is home. Here’s my journey and findings!
The Setup
I have battery-powered D1 Minis equipped with DHT22 sensors in each room. These devices monitor temperature and humidity, which I already use for heating control. The idea is that human activities—like cooking, showering, or even breathing—can cause noticeable changes in humidity levels.
Testing the Concept
I started by observing humidity patterns over a week. When someone was home, I noticed slight humidity increases, especially in the kitchen and bathroom. Conversely, when the house was empty, humidity levels remained stable. This gave me hope that humidity could be a reliable indicator.
Challenges
However, it wasn’t all smooth sailing. I had to account for natural fluctuations caused by things like opening windows or temperature changes. To address this, I set up a threshold-based system where only significant humidity changes trigger actions.
Results
After fine-tuning, the system works surprisingly well! It’s now part of my automation setup, turning on lights and adjusting heating when it detects someone is home. While it’s not foolproof, it’s a fun and creative solution that reduces the need for additional sensors.
Tips for Others
- Calibrate Your System: Spend time understanding your home’s humidity baseline.
- Set Realistic Thresholds: Avoid false triggers by only reacting to meaningful changes.
- Combine with Other Sensors: For more accurate results, pair humidity data with motion sensors or smart plugs.
This project has been a rewarding experiment in creative problem-solving. I’d love to hear if anyone else has tried similar approaches or has tips to improve this method!