There are bionic
and even noses
and robots can see and hear even better than humans. But a sense of touch is
still a challenge. So a group of European researchers turned to whiskers for
Humans can sense quite a bit with their fingertips, but
animals like cats and mice use whiskers as a touch sensor. One
reason for looking to whiskers (otherwise known as vibrissae) is that they're more durable than skin-like sensors placed on robotic fingers, which get a lot of wear and tear. Whiskers are also good for dark places where a camera might not be able to see.
Tony Prescott, a professor of cognitive neuroscience at the
University of Sheffield in the United Kingdom, and Tony Pipe, of the Bristol
Robotics Lab at the University of West England, led a $6.75 million study
called the Biotact project to develop touch sensors. The result
was a number of robotic systems that work something like whiskers and could
enable robots to navigate spaces where cameras won't do any good.
The researchers developed an artificial whisker that
transmits vibrations to its base. A computer picks up those vibrations and can
sense if a surface is rough, smooth, or if there's a corner. The system isn't
just a passive sensor — a set of small motors allows the whisker to be brushed
up against something.
This is, not surprisingly, similar to how rodents and other
animals sense with their whiskers. Mice and shrews move theirs at high speeds
back and forth, for example, for continuous sensing. Part of the initial Biotact studies monitored that
very behavior in Etruscan shrews, tracking how the animals moved their whiskers
to pick up more sensory information.
Another feature of the artificial whiskers is that they are
easy to replace, and can be fitted to a wide range of devices. They can even
work with toys such as Lego robots.
After designing the whiskers, the team built a
"shrewbot" that can navigate by touch alone. It can even track a
moving object with no visual input at all.
Meanwhile, there are more serious applications. Sending a
robot that could sense its way into a fiery, smoke-filled building without having to bump
into things is a much more efficient way of exploring the area. The Biotact
team is also working on an aquatic version.
Credit: University of West England