hardware

Know your parts by kelly heaton

For those of you who don’t recognize electronic components, this guide is for you ⚡️ My installation, “Circuit Garden,” is planted with oversized sculptures of common electronic parts used in nearly every circuit ever made. Hardware components are the media fundamentals of electrical engineering and electronic art — without which we would not have computers or software. They comprise the physical anatomy of machine intelligence. These are: capacitors (electrolytic and ceramic types), transistors, resistors, LEDs, wires, and ICs (integrated circuits, aka chips). Yes, there are other important types of hardware not included in Circuit Garden (or mentioned here), but I’ll sculpt those another time 😉 

Printed Circuit Bird, 2021 by kelly heaton

Printed circuit bird, 2021. I created this work of electronic art to demonstrate the principles by which consciousness originates. The bird's circuitry is entirely analog electronic, which means that her song is not recorded but *generated* by adjustable vibrations in the circuit that forms her body. She is designed to vibrate when exposed to electricity, and we hear the resulting (audible) waveforms as a bird-like sound. Her circuit contains five analog electronic oscillators that are coupled together with a combination of resistors and capacitors. The vibrations of one oscillator affect the others, thus causing a degree of complexity and unpredictability that we wouldn't expect from such a simple circuit. It would be difficult to model this analog system because there are so many possible states, as I will attempt to explain below.

In the video, you see me adjusting variable resistors that affect the frequency, amplitude, and symmetry of the oscillations. The resulting changes in vibration are heard as tonal variation and patterns of sound, or "syntax" of the bird's song. In other words, we can hear the frequency, amplitude, and temporal structure of the waveform as it changes within the bird's circuit. Residual capacitance adds to the unpredictable nature of cause and effect. It is not only which knob I turn or how much, but *when* I make the adjustment relative to the state of the entire connected circuit. These are the continuous, interconnected, analog principles from which life-like behaviors arise. The late roboticist and neuroscientist William Grey Walter experimented with similar principles, notably demonstrated by his tortoise robots.
She is like us — we are electrical beings, too. The neural activity of a human brain is an aggregate of billions of oscillating neurons affecting each other to form thoughts and feelings. While each individual neuron is very simple, the complexity of the neural system is unfathomable. As Nikola Tesla said, "If you want to find the secrets of the universe, think in terms of energy, frequency and vibration." These physical laws are the basis of mind and our conscious universe.

Deep Fake Birdsong by kelly heaton

First causal recording session with Johann Diedrick in which he records my analog electronic songbird and analyzes it with his Flights of Fancy (AI) software to identify bird species. To read more, visit: https://www.kellyheatonstudio.com/deep-fake-birdsong-4

New bird in town by kelly heaton

​I've temporarily relocated the physical form of Hacking Nature's Musicians to the other-worldly environment of Tortuga Escondida (near Akumal, Mexico) for a one-month fellowship on los musicos de la selva​. Thankfully, my supplies made it through airport security and there's air conditioning to protect my electronic equipment against jungle humidity. Here's a photo of my bench showing a view of the jungle canopy and stairs to a roof deck with an amazing panorama over the electrically-charged ecosystem. (Giant scorpions occasionally grace my window screens but I have spared you that visual discomfort.)

My electronics bench at Tortuga Escondida near Akumal, Mexico. October, 2018

A few observations before I jump into the main content of this log: (1) Tortuga Escondida seriously resembles a research facility from the TV series Lost​, so if I disappear you know what happened to me; and (2) the insects here are at least twice the size of their Virginian counterparts. Check out this insane Katydid!

Amazing giant Katydid in the jungle around Tortuga Escondida (greater Akumal, Mexico). October, 2018

Amazing as the insects are, I'm not studying musical bugs because what's most remarkable to me --coming here from Virginia-- are the myriad species of birds. I've decided to see what I can do with the analog electrical engineering of bird song. 

As a starting point, I built a version of the classic, "chirping canary" used in kitschy artificial nature scenes. Check out my files on Hackaday.io for an annotated version of this schematic, which is based on audio transformer oscillation. Basically, the surge in DC power that happens when you first turn the circuit on is capacitively coupled across the transformer and continues to fluctuate thanks to a transistor switch. If you change (or remove) certain capacitor values, the circuit stops oscillating and makes an unpleasant tone that can be very loud due to the current gain across the transformer.

I've made a first informal video​ showing how the sound changes when different parts of the circuit are modified (apologies in advanced for some unpleasant beeps - don't wear headphones).

Next, I built a few astable multivibrators and connected them to various aspects of the sound-generating circuit in order to make the chirp sound more like a bird song. Some of my tests are documented in a second video that you can watch on Vimeo.

Watch the green LEDs (and follow the white wires) to get a sense for what the astable multivibrators are doing. 

Birds are very clever singer-songwriters, so it's going to take a lot more work on tempo and pitch variation to get interesting songs. I plan to try numerous strategies to generate voice quality because I want to build a jungle of different bird circuits ranging from sparrows to whippoorwills to parrots to owls to a Resplendent Quetzal, relative of the legendary Mayan Plumed Serpent. If you have suggestions for circuits to try, I would be grateful.

So... not only do my bird electronics need work, I could use a new "avian speaker" design. It seems that piezo buzzers are better suited to insects, while 8 ohm speakers have higher bird fidelity. Initially, this observation puzzled me (and I'm still not clear) but I got some useful clues from the ingenious musician, Nicolas Bras.​ It's material physics: the thin, metal vibrations of a piezo disk have more in common with the chitin instrumentation of an invertebrate than the fleshy air bladder and vocal chords of a squawking bird. Some insects do force air through a membrane, like living kazoos, but crickets rely heavily on the idiophonic effects of leg or wing rubbing. The sound made by an idiophone is quite different than that of an aerophone or membranophone, like hitting a cymbal versus blowing through a reed, the latter of which happens when a bird forces air through its vocal cords. I searched the web for homemade instruments that behave like an aerophone with a membrane and found this cool "membranophone" video​ by tachionics. 

As I did with my "insect-like" piezo, I'd like to build an electronically actuated speaker that has material properties more in common with a bird. I've got various 8 ohm speakers that are working for now, but I suspect that there's a better design to be made -- or at least some cool insights to discover in the process of trying. Again, your suggestions are greatly appreciated!

Stay tuned.

This tarantula was found dead, but I couldn’t resist photographing its exquisite corpse. Impressive creature!