Underwater ‘pokéball’ can catch some of the rarest creatures of them all

19 Jul 2018

The RAD sampler has five origami-inspired ‘petals’ arranged around a central point that fold up to safely capture marine organisms, like this jellyfish. Image: Wyss Institute at Harvard University

There’s a lot of ocean to cover for marine biologists, but a new device aims to help catch, study and delicately release some of the rarest creatures.

In many respects we know more about the planet Mars than we do about our own oceans, keeping many marine biologists occupied finding and studying hundreds of thousands of undiscovered creatures.

But at such extreme depths and remote locations, scientifically analysing a fragile sea creature without damaging it or bringing it to the surface has been a major challenge.

Now, however, a team of engineers at Harvard University’s Wyss Institute has helped create a ‘pokéball’ device that can safely capture these creatures, let them be analysed and then, soon after, released again to their natural habitat.

Unlike the device from Pokémon, however, the device is a polyhedral shape consisting of five identical 3D-printed polymer ‘petals’ attached to a series of rotating joints linked together to form a scaffold.

When a single motor applies a torque to the point where the petals meet, it causes the entire structure to rotate about its joints and fold up into a hollow dodecahedron, hence why it is called the rotary actuated dodecahedron (RAD) sampler.

Publishing their findings in Science Robotics, the team led by Zhi Ern Teoh tested the sampler at a nearby aquarium, successfully collecting and releasing moon jellyfish underwater.

‘An underwater alien abduction’

After some modifications to allow it to withstand ocean conditions, the RAD was mounted on an underwater remotely operated vehicle (ROV) and subjected to depths of up to 2,300ft, with the ROV’s mechanical arm controlling the sampler.

Again, the device successfully captured and released delicate organisms such as squid and jellyfish.

“The RAD sampler design is perfect for the difficult environment of the deep ocean because its controls are very simple, so there are fewer elements that can break,” Teoh said.

“It’s also modular, so if something does break, we can simply replace that part and send the sampler back down into the water.”

The design isn’t completed just yet, as the team wants to make it even more rugged for tougher underwater tasks such as marine geology and also attach scientific instruments to make it a real mobile lab.

The study’s collaborating author David Gruber added: “We’d like to add cameras and sensors to the sampler so that, in the future, we can capture an animal, collect lots of data about it like its size, material properties and even its genome, and then let it go, almost like an underwater alien abduction.”

Colm Gorey was a senior journalist with Silicon Republic