Any time you hear a piece of machinery making noise, it is an indication of inefficient design. The noise is excess energy. Engineers continually strive to design machinery in the most efficient way, but apparently we need some technological breakthroughs to eradicate the noise altogether. It is interesting to see those science fiction movies that show low-flying airplanes that are completely silent. One day it will probably happen.
As I listen to the obnoxious sounds of leaf blowers, I am reminded that the U.S. EPA says noise degrades our quality of life by impairing communication and social interaction. It reduces the accuracy of work and it also creates stressful levels of frustration and aggravation that last even when the noise has stopped. It doesn’t have to be this way.
During one of my green innovation field trips, while learning some of the principles of biomimetics, I walked through a rainforest with engineers who worked for a well-known airplane manufacturer. They were looking for nature’s answers to noise to find new ways of reducing the noise inside an airplane. Their challenge was to find ways to do this while not adding any materials, such as a fiberglass blanket, to absorb sound, and thereby increase weight.
Leaf cutter ants, for example, produce high frequency vibrations through their mandibles that cause leaves to stiffen, enabling them to cut pieces. Spiders sit in their webs waiting to catch insects. The vibrations caused by the insect alerts the spider to its next meal. Both are examples of using the energy of sound, through vibrations, to positive ends. If the engineers could determine where vibrations occur most in the plane, they mused, then maybe they could design a structure to dampen the noise.
The Kingfisher bird has a long beak and can withstand sudden changes of air pressure as it dives into the water to hunt for food. The Japanese, who have one of the most stringent noise standards in the world, used this bird’s beak as a model to design the front car of the Bullet Train to eliminate the sonic boom that occurred upon exiting tunnels.
There are plenty more examples of nature-inspired innovations in just about every area of human need for improvement. But I have to go right now because the noise of a nearby chainsaw is becoming irritating and affecting my concentration. I’ll be back with much more.