Enormous schools of fish are amongst the most jaw-dropping sights in the natural world, with thousands of tiny fish synchronizing their behavior and movement to find food, migrate, and escape predators.
A team of researchers from Harvard University has mimicked this pattern of behavior with a robotic swarm, dubbed Blueswarm, that synchronizes its movement without external control. Their research is published in Science Robotics.
Blueswarm's fish-like robotic coordination
Schools of fish synchronize their behavior without a leader: each individual fish makes decisions based on what their neighbors are doing, through a natural process called implicit coordination.
Fascinated by this type of decentralized self-organization, the team from Harvard set out to develop a school of fish-like robots that could synchronize much in the same way as fish in the natural world.
Through their efforts, they developed the first underwater robots to exhibit complex 3D collective behaviors with implicit coordination.
"Robots are often deployed in areas that are inaccessible or dangerous to humans, areas where human intervention might not even be possible," Florian Berlinger, a Ph.D. Candidate at SEAS and Wyss and first author of the paper, explained in a press release.
"In these situations, it really benefits you to have a highly autonomous robot swarm that is self-sufficient. By using implicit rules and 3D visual perception, we were able to create a system that has a high degree of autonomy and flexibility underwater where things like GPS and WiFi are not accessible."
Complex synchronized behavior
In order to develop their robots, the researchers created a vision-based coordination system based on blue LED lights. Each individual fish robot, called a Bluebot, is equipped with two cameras and three LED lights.
An on-board fish-lens camera, which looks remarkably like a real fish eye, detects the LEDs of neighboring Bluebots and utilizes a custom algorithm to determine their location and movement.
The researchers showed that Blueswarm is capable of demonstrating complex synchronized behavior such as aggregation, dispersion, and circle formation.
The researchers say that insight from this project hopefully help them develop miniature underwater swarms that are capable of performing environmental monitoring and even search missions in fragile environments like coral reefs, to help protect the environment.