For the Duel nature sculpure, I wanted to have a ‘breathing’ pattern where all the LEDs vary in brightness in a natural/organic way. A good example is the ‘sleep indicator’ LED on recent Macs/Powerbooks. (There’s even a patent!) The problem is that, while the patent claims its a simple sinusoid (see the patent for the image), programming in a sinusoid doesn’t look nearly as good. So I decided to get the real waveform with a kludgy reverse engineering attempt:
[flickr 212611715 ]I used a MIDIsense instead of a simple voltage divider because I want to extract the absolute LED brightness pattern and a photocell voltage divider acts ‘inversely’ (well, 1/R) instead of linearly (ie, just R). (The MIDIsense has an opamp to linearize the resistive sensor output)
[flickr 212611654 ]
There it is! There is a bit of ‘noise’ on the peaks because I’m picking up some of the PWM artifacts through the diffused white plastic.
Join 4,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord
Learn “How Computers Work” with Bill Gates, Ladyada and more – From Code.org !
CircuitPython in 2018 – Python on Microcontrollers is here!
Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.
Join us every Wednesday night at 8pm ET for Ask an Engineer!
Follow Adafruit on Instagram for top secret new products, behinds the scenes and more https://www.instagram.com/adafruit/
Maker Business — Looking back at Electric Objects, a postmortem of a hardware startup #makerbusiness
Wearables — Don’t be wooden
Electronics — Here’s the low-down on inductive loads
Biohacking — Muse EEG Utilities for Capture, Conversion and Visualization of Brain Waves
Python for Microcontrollers — CircuitPython Team on Ask an Engineer
Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com
Sorry, the comment form is closed at this time.