Meet Cornelia - AUT's robot turtle
A robot-turtle created by Auckland University of Technology scientists has shed light on how endangered green sea turtles can swim more than a marathon a day, while eating just algae and seagrass.
The discovery could lead to the development of a new generation of turtle-inspired underwater robots to aid the conservation and monitoring of our oceans.
The green sea turtle (Chelonia mydas) can swim up to 50 kilometres a day, despite consuming a low energy diet of seagrass and microalgae.
This is due to the animals’ special swimming technique, which has now been mimicked by a robot turtle called Cornelia – named in honour of PhD researcher Nick van der Geest’s grandmother, who died just before the robot’s first swim.
AUT Biodesign engineer and lead researcher Dr Lorenzo Garcia, and van der Geest, who is completing his PhD at AUT, say creating the robot allows experimentation while removing ethical issues related to animal testing - especially where endangered species are involved.
“Even if we were to experiment on a captive turtle, it may not swim with its regular routine in an aquarium setting,” Dr Garcia says.
By experimenting with the robot turtle, the team found the species may only produce propulsion for approximately 30 percent of each flipper cycle, meaning the remaining 70 percent of the movement uses very little power, while also creating very little drag.
This enables green sea turtles to swim such long distances, despite consuming very little energy.
Dr Garcia hopes the AUT team’s research, published this week in Nature – Scientific Reports, will lead to the creation of a “new generation of robotic systems for ocean exploration that use an optimised derivative of the sea turtle propulsive strategy.”
In 2021, Dr Garcia secured $200,000 from the New Zealand Government’s Science for Technological Innovation fund to develop a bio-inspired underwater robot. The results of this research bring Dr Garcia and his team closer to this goal.