Whisker-possessing, rodent-like robots with innovative tactile sensor systems have been developed that could have a number of applications, including helping to locate people in burning buildings.
Sensor systems that replicate the sense of touch have been the focus of increasing research in recent years, but the focus has normally been on developing sensors that replicate the way humans touch and sense the world: particularly the fingertips. However, fingertip sensors are vulnerable to wear and tear. A far more robust and sensitive tactile sensing device already exists in nature: whiskers.
“If you look at the natural world, almost all mammals except humans have whiskers – it’s actually us that have lost them. Whiskers are a natural way to sense things with touch,” said Professor of Cognitive Neuroscience at Sheffield University Tony Prescott.
A team of researchers, including Prescott, from seven different countries make up Biotact, whose work aims to develop novel tactile sensory technologies. The researchers studied rats, mice and tiny Etruscan shrews and attempted to replicate the way they use their whiskers to sense their environment, detect objects and follow prey. Their work lead to the development of a series of rat-like robots that are able to move around by touch alone.
The team then worked out how to replicate natural whisker sensing in an artificial system by measuring the vibration produced at the base of the whisker when it comes into contact with an object. Miniature motors enable the individual robot whiskers to move back-and-forth at high speed. Powerful processing algorithms analyse feedback to determine the properties of an object.
Applied to robotic devices, this active sensing greatly improves the accuracy and effectiveness of the sensors, enabling a robot to delicately feel its way round, rather than clumsily bump into objects.
Shrewbot is the team’s latest development and can navigate its way around by touch alone, just like its namesake. A shrew-like robot could have many future uses, for example, to help fire-fighters find people in burning buildings, or other environments where smoke, dust or darkness impede visual sensing.