I've been following the development of robotics for about 10 years and my background is Biology and Videography. These interests have orbited my underlying passion, entomology (the study of insects). Insects are a big deal in many industries, and have been the source of a great deal of inspiration. Thankfully, biology and insects are gaining clout in robotics through biomimicry and synthetic biology. I am especially excited by the progress of insectothopters. The CIA created a flying insectothopter as early as the 1970's and insects will continue to play a large roll in influencing how problems in robotics are solved. I want to share an artistic method of building your own electromechanical insect sculpture.
One craft that has focused heavily on the properties of insects is the art of fly tying. Fly Tying is a method of creating lures for fly fishing. This craft employs a diverse palette of materials and tools, and requires careful attention to detail, while heavily relying on proper technique to complete beautiful designs.
I have not gotten too excited about 3D printing or Microcontrollers. I am making efforts to produce electromechanical creatures that use neither of these technologies. It seems that no matter what sensor or mechanical expression you want to explore, it all has to feed through a microcontroller. Lets take it back a bit and make our brain, an oscillator!
So what I propose to you is, we use fly tying tools, materials, and technique as a foundation for creating a beautiful, lightweight, unique, electromechanical insect. This BEAM-like kinetic sculpture will hopefully inspire your friends and family to appreciate insects and craftsmanship.
There are many oscillator circuits to choose from online. After
looking into a variety, I felt that the easiest and most "organic" was the Astable Multivibrator. This circuit can be created with symmetrical resistors or asymmetrical, resulting in slightly different pulse widths, depending on which "side" of the circuit your are taking your output from.
The components for this circuit I chose are:
x1 2N4403 pnp transistor
x1 2N3905 pnp transistor (mirrored pin out)
x2 330 Ω resistors
x2 22k Ω resistors
x2 4.7 μF 16V capacitors
x2 Light Dependent Resistors (LDR) in 0 - 30k Ω range
x1 2N4920 pnp transistor (handles 1 amp)
x1 8+ Ω Speaker coil
x1 Small nonmagnetic, not enclosed reed switch
I want a low RC time and small capacitors, so I chose 22k Ω resistors with 4.7 μF 16V bipolar Capacitors. This results in roughly 2 - 5 Hz oscillation frequency.
I also want the circuit to be effected by the environment, so I put light dependent resistors (LDR) in series with the 22k resistors. The switch is a small reed switch pulled from a disposable camera flash circuit. We'll use this switch as sensitive whiskers on the abdomen.