SlugBot: Enemy of Slugs
By Louise Knapp
In the near future, the very mention of SlugBot could send waves of terror
through the slug community, while farmers will sing its praises.
A prototype robot capable of hunting down over 100 slugs an hour and using
their rotting bodies to generate electricity is being developed by engineers
at the University of West England's Intelligent Autonomous Systems Laboratory.
The SlugBot is an attempt to build the world's first fully autonomous robot.
When completed, the SlugBot will be the first robot to work completely
independent of human care. It won't even need help to recharge its batteries.
"Slugs are slow," said Dr. Ian Kelly, SlugBot's creator. "You can't expect the
speeds of a cheetah chasing a zebra. Slugs are small and manageable."
Resembling a DJ's turntable mounted on four wheels, the robot has a carbon
fiber arm with a three-fingered claw grabber at the end. The claw is equipped
with an electronic eye for finding its slimy prey and scrapers for wiping off
The robot's arm can rotate through 360 degrees and reach nearly 2 meters in
any direction, including upwards.
"It takes a lot of energy to move over rough terrain," said Kelly who is
currently working at the Collective Robotics Research Group at California's
Institute of Technology. "Having a long reach means the robot does not have to
move around so much."
The SlugBot uses an electronic eye mounted on its claw to ferret out slugs,
which are nocturnal.
Slugs are difficult to see at night with the naked eye, but show up as bright
blobs in the SlugBot's image sensor when illuminated with a special red lamp.
When it spots a slug, the SlugBot picks it up and drops it into an on-board
hopper, which is about the size of a two-liter ice cream container.
"There is a problem with stopping the captured slugs from climbing out," Kelly
said. "We may utilize a low-energy electronic shock system to keep them in the
The SlugBot navigates using a combination of the Global Positioning Satellite
(GPS) system, and an active infrared localization system. It detects obstacles
through a combination of ultrasonic sonar and bump sensors.
After a hard night of slug hunting, the robot returns to home base and unloads
its victims into a fermentation tank.
And while the SlugBot recharges, the fermentation station is busy turning slug
sludge into electricity.
Decomposing bacteria converts the slugs into a combustible bio-gas, which is
then loaded into a fuel cell to generate electricity.
Kelly and his team decided to use slugs as a source of energy for an
autonomous robot because they are so easy to capture. They also have no
exoskeleton, which makes them easier to break down in the robot's digestive
Slugs are also plentiful; up to 200 slugs can be found per square meter in
fields of winter wheat, which makes them a major pest. About $30 million a
year is spent in Great Britain alone trying to eradicate the slimy critters.
Kelly said he'd like to see armies of coordinated SlugBots protecting
farmland, eradicating slugs from farmers' crops.
"The robots will share a map between them showing where the greater density of
slugs are and allowing them to coordinate so they don't get into each other's
way and so they don't go back to the same area two days in a row," Kelly said.
Kelly said one of the main advantages of SlugBot is that it may help phase out
molluscicides, harmful pesticides that kill slugs and snails.
"Molluscicides have the side effect of killing off other things and because
they are used in such high quantities they can get into the ground water,"
So far, the team has built a prototype SlugBot, which has cost around $3,000
in parts. Kelly said the price would come down if the robot went into mass
production. And of course, there are few ongoing expenses.
The SlugBot will not, however, be ready for the production line for at least
another three to four years.
So far, it has been tested only in the lab. Kelly said it has correctly
identified and homed in on slugs, but has trouble picking them up, especially
if they are partly nestled in dirt.
"We have accomplished the hard part of the research by getting the robot to
identify the slug," Kelly said.
Diane Schivera, assistant director of technical services with the Maine
Organic Farmers and Gardeners Association, said smaller growers probably
couldn't afford slug-eating robots.
"Using copper tape as a deterrent or Remay (a thin fabric cover) would
probably be less expensive," Schivera said. "Plants are only at risk from
slugs when they are babies, so these methods for smaller farmers work."
However, Schivera said that increasing pressure to move away from pesticides
may cause some farmers to consider it.
"For bigger farmers it may be something that might work," Schivera said.
"Those with extra cash to blow on something like this."
--- --- --- --- ---
Useless hypotheses, etc.:
consciousness, phlogiston, philosophy, vitalism, mind, free will, qualia,
analog computing, cultural relativism, GAC, Cyc, Eliza, cryonics, individual
uniqueness, ego, human values, scientific relinquishment
We move into a better future in proportion as science displaces superstition.
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