I am trying to build an arduino project with the following requirements:
- Proximity sensors detect human presence and its distance
- The sensors are hidden behind fabric
- Range has to be 1-3 meters or higher
- It is for indoor use
After a bit of trial and errors, here are my initial conclusions:
-
Available light changes, and sensors being behind the fabric, photo sensors are out of the question
-
Even though they're not supposed to be very sensitive to soft material, Ultrasonic sensors such as the HC-SR04 don't fit. Their echo bounce right off the fabric
-
Pir Motion sensors don't read through fabric either
I am starting to wonder if this is even feasible. Is there such thing as a proximity sensor that reads through soft material?
Best Answer
You could try a Doppler radar sensor such as the ~10GHz motion sensor modules which are available on the surplus market and from China.
As unlicensed and likely unapproved intentional emitters, they are probably of dubious legality to use, if that bothers you. They're probably safe to use (aside from possible interference with other electronics) but caution is called for- some people get sensitive if they think their DNA might get scrambled or their 'nads nuked.