A spherical roving robot designed to detect and report intruders has
been developed by a Swedish start-up company.
The design was first developed with planetary exploration in mind, at
the Ångström Space Technology Center, part of Uppsala University,
Sweden. But Rotundus, formed in December 2004 plan to market the
ball-shaped bot as an automated security guard.
"We knew it would have applications on Earth," says company CEO Nils
Hulth. "It is very robust when compared to robots that use wheels or
tracks and can travel through mud or even snow."
It is propelled by a pendulum suspended from an axis inside the casing,
controlled by a motor. Moving the pendulum forwards causes the robot
roll along, but the pendulum can also swing from side to side, giving
the robot the ability to steer left and right. An animation
<http://rotundus.se/animation.mpg> also available on the Rotundus
website illustrates the locomotion mechanism in action.
Patrol route
The finished version of the robot will follow a patrol route using an
internal GPS sensor, Hulth says. Wide angle cameras fitted to the sides
of the robot should allow it to record and transmit video footage back
to a controller. And the next version will also have enough power to
propel itself up slopes, he says.
Ultimately, the company hopes to make the robot virtually autonomous. It
is currently developing a radar sensor to allow it to navigate around
obstacles and motion-sensing software to automatically detect an
intruder. "It will sound the alarm, allowing a remote controller to take
over and get even better pictures," Hulth says.
Tony Hirst, a roboticist with the Open University in Milton Keynes, UK,
told *New Scientist* the robot's spherical design could make it more
nimble than other robots in certain situations. It would be less prone
to getting stuck in corner, for example. Hirst also notes that some US
companies already offer indoor security robots that can autonomously
patrol a factory floor.
Hulth concedes that the robot is not well suited to navigating inside a
building, where it would face steps, stairs and other obstacles.
Scrambling legs
Other robots being developed could be much better suited to indoor
tasks, however. For example, researchers at Case Western University in
Cleveland, US, are working on insect-inspired bots that can overcome
irregular surfaces and steps.
These robots use a combination of wheels and legs to scramble over
terrain and are therefore dubbed "whegs". A video
<http://biorobots.cwru.edu/Projects/whegs/ICRAminiwhegs_web.mpg> (35MB
mpeg) of various whegs in action reveals a form of locomotion akin to
that of a large insect.
"Three spoked appendages, called wheel-legs, combine the speed and
simplicity of wheels with the high mobility of legs," the researchers
write on the project's website. "The robot can surmount obstacles
significantly greater than the radius of the wheel-legs - a difficult
feat for wheeled vehicles."