Scientists at the Trinity College in Dublin, Ireland have begun studying how to integrate the functionalities of insect legs with modern aircraft designs in order to reduce their weight and make them safer for passengers.

Trinity College professor David Taylor and his team of researchers examined the legs of well-known insects, such as bees, cockroaches, locusts and stick insects, to understand how they are able to buckle and bend when pressure is applied to these legs.

Their goal is to incorporate this concept to improve the durability of tubular structures used in aircrafts and hospital equipment.

"Thin-walled tubes are prone to failure by buckling," Taylor said.

"It is difficult to predict the loading conditions which cause buckling, especially for tubes of non-standard cross section. Think of a drinking straw. If you bend it, it will suddenly give."

For their research, Taylor and his colleagues selected insects with varying leg shapes and lifestyles.

The legs of stick insects feature five long ridges running down each appendage. While these ridges do not protect the legs from the effects of buckling, they do keep them intact.

Taylor said the ridges help the insect's legs to resist a form of buckling known as elastic buckling. The trait shows how geometry and material properties could potentially react in complicated ways, which have to be considered in making designs for tubes with thin walls.

The legs of bees have a triangular mid-section with a wide flat area. This is where the insects keep their pollen basket when they gather their food. The researchers discovered that this design did not hamper the bending movement of insects' legs, proving that materials with non-circular mid-sections can be made without sacrificing its mechanical strength.

The legs of cockroaches and locusts are hollow with mid-sections that are almost circular. These sections allow the insects' legs to come close to breaking whenever they jump. Taylor pointed out that this trait demonstrates how evolution operates close to its limit.

The researchers believe that by understanding how insect cuticle functions, it can lead to the development of nature-inspired biomimetic materials.

"Even though the arthropod cuticle is one of the most common materials in the world, we don't know very much about it", Taylor said.

The researchers will now determine how living insects respond to pressure as part of the next stage of their study.

The findings of the Trinity College Dublin study are being presented at the meeting of the Society for Experimental Biology.

Photo: Till Westermayer | Flickr