Help with Distance sensor

Hi all, so this is a call for help on a school project.
The general idea is to give a certain amount of people entering a building a bracelet which will detect if there is another bracelet in a 6 feet perimeter and will be able to be detected from others as well.
I have certain questions;

  1. Are we able to have arduino as a server and hand the "lab rats" just the detectors and the thing to be detected? The idea behind it to connect them in a WIFI (I guess) to work and send the data back
  2. What parts do i need to use? I googled it and apparently Inductive Proximity Sensor are not good enough because they only detect metal.

I am happy to hear everyone's advice and thanks for your time in advance



Measuring distance through RSSI of either BT or Wi-Fi won't work precisely enough as 2.4Ghz is too sensitive to obstacles (water especially - and human body is lots of water).

You would also get false positive if 2 students stand next to each other but separated by a classroom wall (which is then zero COVID risk if this is your use case scenario)

I've not seen robust solutions in the consumer DIY space for indoor positioning.

Measuring distance like You want is a common question here and I have not heard that anyone has managed. Lots of time has been dpent on endless discussions.

What I meant is that if we take a small chip adjust it into a bracelet with a sensor for the -let's call it- X thing are we able to connect it with WiFi and send data back telling us how many times the sensor detected the X thing?
Which detector shall I use and what will the X thing be?

PS the experiment will be in a supermarket so it is not really a problem the thing about classrooms :slight_smile:

do you mind seeing my answer to the fellow guy? thanks :slight_smile:

Unfortunatly, that doesn't change anything.

Are you looking at doing something reliable? We are telling you nothing within reach of your budget and probably time available and RF skills will match your specs (making some assumptions there it’s a school demonstrator).

If you have a few years ahead of you and tens of millions of dollars and access to a few PhD assisting then you might get somewhere

Look at Apple just released air tags for example, it’s full of technology and custom chips in the 10GHz band and broadcast a signal that iPhone will pick up but they will only give you an good enough approximation of direction and estimate of distance and that after probably hunderds of millions in investment and R&D
Look at what’s inside

yes, it's the right answer.