30 Mar More efficient robots from marine fauna
Soft robots are still a niche within the field of robotics, but research is very active and projections suggest a growing market, expected to surpass a turnover of three billion dollars in 2023. Meeting the challenges of creating systems capable of making precise and energy-efficient movements is a complex task.
Nature is one of the main sources of inspiration, and every now and again we hear of new discoveries and insights. A recent case involves sea snails, which are marine invertebrates that vaguely resemble land snails. They are classified as gastropods, a Greek term that means they move by crawling on their stomachs. What distinguishes them from more familiar molluscs is that they don’t have a shell or conchilia, which has either disappeared or been confined to their bodies through evolution.
The link to a future generation of energy-efficient and extremely flexible soft body robots lies in the frilly surface of their bodies. In mathematical terms, this surface is referred to as an “inflected nonsmooth surface”, characterised by its irregularity and ability to bend, leading to changes in direction based on how it bends. Until recently, this unique characteristic had not been thoroughly investigated, but researchers at the University of Arizona have filled the gap. They developed a mathematical model and applied it to a thin plastic film, confirming that the surface bending, without energy-consuming stretching and contraction, was sufficient to achieve controlled movement.
The challenge now is to understand precisely how the smooth gliding movements of marine invertebrates are related to the specific surface structure of their bodies and then to transfer the experimental findings to create flexible soft-body robots that can move around without expending energy.