Future of Engineering

Here's another invention inspired by an insect. Zoologist Andrew Parker of the University of Oxford in the United Kingdom studied the Namibian desert beetle, Stenocara, and has figured out it captures water from the wind. Stenocara genus is a beetle that lives in southwestern Africa’s Namib Desert and draws on fog as its sole source of water.

The beetle collects drinking water using its wings, which are waxed and covered with an array of raised unwaxed bumps. The bumps strongly attract water, while the waxy areas repel it. Namib beetle faces the wind and droplets of water stick to the bumps on its back. This water builds up before rolling down the water-repelling channels on the beetle's back and into its mouth.

Researchers have now found a way to copy the design and modify it. They can decorate a surface with any microscopic pattern of water-attracting and water-repelling areas, leading to various possible applications.

Christian Dorrer and Jürgen Rühe of the University of Freiburg in Germany have created a surface that attracts fog’s microscopic water droplets, encouraging them to condense. Once the droplets get too large, the surface lets them slip away so they can be collected.

A thin carpet of silicon spikes is coated with a highly water-repellent organic material. It is then painted with a polka dot pattern on top of the surface, this time using a water-loving material. Water droplets from fog will tend to stick to the water-loving dots (and merge with one another). Meanwhile, droplets that condense on the water-repellent areas will tend to drift down, until they run across a water-loving region and merge with other droplets.

This invention could be useful in remote areas that lack access to drinking water.The technology could also help scrub pollutant mists in industrial smokestacks. It is a good model for designing inexpensive tent coverings and roof tiles that could collect water for drinking and agriculture in arid regions.

Source - ScienceNews