Engineering news
Scientists have created autonomous underwater robot swarms that function like schools of fish, exchanging information to monitor the environment, searching, maintaining, exploring and harvesting resources in underwater habitats.
Dr. Thomas Schmickl, coodinator of the EU supported COCORO project and associate professor in the Department of Zoology at the University of Graz in Austria, said that the robot swarms are capable of collective cognition and work as a “collective system of autonomous agents” that can learn from past experience and their environment.
Researchers developed three different robot types, including 'Jeff' and 'Lily' robots. Jeff robots use a bio-inspired method to spread a one-bit signal using LEDs among the swarm, called the “fireslime algorithim”, to achieve a form of collective awareness. 'Lily' robots are able to estimate their swarm size by emitting a pulsed signal relayed by other Lily robots – a method inspired by slime mould amoebas that congregate using chemical waves to communicate with each other.
In one experiment, the robots were tasked with the mission to find debris originating from a sunken airplane. Lily robots were used to search just below the surface, while Jeff robots searched at the bottom of the pool.
Magnets were placed around the airplane to mimic an electro-magnetic signal emitted locally and the robots used their built-in compasses to locate the target. A Jeff robot soon discovered the target and settled on it at the bottom of the pool.
By transmitting LED, it ‘recruited’ the other Jeff robots, which then gathered around the target, while Lily robots collected overhead.
During field trials in Livorno Harbour, Italy, the robots were exposed to waves, currents and corrosive salt water. Despite the difficult conditions researchers found the robot swarms were able to remain clustered around their base station as well as go on “patrols” and successfully return to base.
COCORO’s scientists have also modelled other collective cognition in nature. For example, observing how honeybees cluster helped them to develop the BEECLUST algorithm that they used to aggregate robots at a specific location.