⚡ Maya Murad

Project 9:
Input Devices

                                             The Challenge

Measure something: add a sensor to a microcontroller board that you have designed and read it. [Individual]

Probe an input device's analog levels and digital signals. [Group]

Link to Arch section group page

                                                   The Motivation

I wanted to leverage this week to try some sensors that I could use for my final project. The spirit of the final project is to creative a light installation that responds to its environment. This week I attempted to experiment with motion detection and light (potentially RGB) sensing.

                                             Motion Detection

I first worked with the RCWL-0516 module, which leverages the Doppler effect to detect moving objects.
Important characteristics of the module:
  • Sensitivity range of ~7m
  • Outputs 0V when no motion
  • Outputs 3.3V for 2-3sec when motion detected

As I couldn't find a detailed datasheet online for this part, I used this Github page which I found helpful.

RCWL-0516 Microwave Proximity Sensor

Board schematic with header to connect to RCWL-0516, 2 LEDs and using ATtiny1614.

Resulting board created in Eagle

Simple script to run motion sensor in Arduino

Serial monitor readings of RCWL-0516 motion sensor from Maya Mourad on Vimeo.

                                             Luminosity sensing

I created a second board to work with a phototransistor and RGB LED.
I was able to test the luminosity in an ambient room and that worked pretty well. I also attempted to use this set-up as a color sensor to capture the intensity of incoming light after R/G/B are respectively flashed by the LED. There seems to be something wrong with RGB LEB setup where it only flashes R/B and not G. I went throught the checklist of things to sort it out (changed the part, checked soldering/wiring/code) but have not figured it out yet.

Luminosity sensing schematic + board

Phototransistor test from Maya Mourad on Vimeo.