At UFO, my intern and I built and tested an electric earthworm separator. This is an electric appliance developed by UFO, but yet commercialized.
Fig. 1. Testing the electric separation of earthworms
The project was funded by a Carrot Cache grant and the experiment conducted at the Thing Tank lab. I designed the separator and selected the electric current level and type based on the design model I published in Biosystems Engineering. The tests showed that the separator can drive 50% of the earthworm in a soil or organic medium, without harming them, by using low AC voltages (see Fig. 1).
Fig. 2. Prototype and designed version of the electric earthworm separator
The electric earthworm separator is essentially an array of semi-cylindrical channels, with soil electrodes running parallel to the two opposite edges of the channel (see Fig. 2). Soil containing earthworms is poured over the array of channels, and the separator has a mechanism to discard excess soil so that soil is only found on the inside of the channels. An electric circuit is then turned on for 2 minutes, and earthworms exit the perforated channels filled with soil, onto a platform underneath the channels. From there earthworm earthworm are simply collected, typically to be sold. Here is a video of the separator in action (Fig. 3).
Fig. 3. Video of earthworms exiting the soil under the effect of electric current
UFO’s industrial designer created a designed, digital model of the electric separator (Fig 2). After prototyping this idea, I actually realized that vibrations, from low-frequency radio-waves (like a loud speaker playing base) would be more pratical for driving earthworms out of the soil. This was a useful prototyping experience none-the-less. I hope to follow up soon with a sound-based method from driving earthworms out of the soil, or processed waste.
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