Autonomous swimming robot inspired by the sea turtle
By Ben Coxworth
October 2, 2012
Well, we shouldn’t be surprised. Scientists have created swimming robotic versions of the cow-nosed ray, the jellyfish, the sunfish, the tuna, and just the generic “fish,” so why not the sea turtle? That’s what a group of scientists from the ETH Zurich research group are in the process of doing, and they’ve named it naro - tartaruga (the original naro was another robotic tuna). As it turns out, a couple of the sea turtle’s natural features make for a pretty good robot.
First of all, if you’ve ever swam with one, you’ll know that sea turtles are fast and maneuverable. naro - tartaruga is likewise intended to be fast, with an estimated top speed of two meters (6.6 feet) per second. It should also be quite maneuverable, with its two front flippers being able to move independently – each fin is controlled by three actuators, allowing for movement in three dimensions.
The other natural feature of turtles that's being being put to use is that big domed shell. Instead of being stuffed with turtle guts, on the aluminum-hulled robot it will be used to house a variety of sensors and other electronics. These will include pressure, temperature, water leakage and water flow sensors, along with gyros, surface GPS, a compass, and motor encoders.
Also along for the ride will be an i7 dual core processor, a 48-volt lithium-polymer battery pack, and a BlueFox computer vision system. Everything should add up to a combined weight of about 75 kilograms (165 lbs), and fit within a body approximately one meter (3.3 feet) long. Interfaces at the head and tail will allow different modules to be swapped in, depending on the robot’s intended use.
Although it is possible to operate the current prototype by remote control, naro - tartaruga is being created first and foremost as an exercise in autonomous underwater navigation. The research team is also interested in seeing just how energy-efficient its flapping-fin propulsion system will be.
naro - tartaruga has been in development since 2010, but it is scheduled to make its first dive this month.