The Importance of Shape

The performance of many products is governed by shape – the shape of a windmill blade, for example, affects its ability to catch the wind and produce power. The conventional wisdom has been to engineer the blade to be aerodynamically smooth. But a new wisdom – in fact, the wisdom of the ages – is leading to design of better windmill blades.

In nature, the flipper of a whale may be considered a good surrogate for designing the shape of a windmill blade. It is reasonable to presume that whales with the most efficiently-shaped flippers struggle the least to propel themselves through the ocean, and therefore have thrived. Whale flippers are seen to have a series of bumps creating a scalloped edge. A prototype windmill blade designed with similar bumps has been shown to increase annual electric production by 20% while greatly reducing noise.

For more information visit:

While recognizing the clue to include a scalloped edge is biomimicry, traditional engineering efforts are still needed to ultimately balance the design tradeoffs between optimally-efficient shape and ease of manufacture in order to maximize profitability.

In nature, various plants and animals have tried numerous shape factors, and those offering energy efficiency have flourished. Designers have emulated these shapes specifically for their energy efficiency (such as the Chrysler car patterned after the boxfish, a reef-dwelling fish), or have chosen nature’s shapes for other reasons but have discovered happily that the shape also yields an energy efficiency gain (such as the Japanese Bullet Train, which was re-designed in the shape of the Kingfisher bird to control a sonic boom).

In addition to shape-factor, inventors are learning from nature regarding clean and efficient material properties and manufacturing techniques, such as the durability of sea shells compared to traditional ceramics, strength-to-weight advantages of spider silk compared to steel or Kevlar® fibers, and non-toxic waterproof glue modeled after mussel adhesives.