Swarms of 3D printed sea slug bots could be coming to our oceans

20 Jul 2016

Soft robotics research has reached new depths with researchers with the creation of a crawling 3D-printed robot built from sea slug parts ushering in an era of ‘biohybrid’ robots.

This latest advancement in the weird and wonderful world of bio-inspired robots has been developed by a team from Case Western Reserve University in the US which wanted to take the qualities of a common sea slug and use it to create something otherworldly.

While the mechanics of the robot have been built and assembled using 3D printed parts, much of the tiny robot’s outer casing has been built using various parts from the slug, including a muscle from its mouth which provides movement.

Largely built from body parts of an underwater creature, the team has hypothesised using its creation underwater, released in swarms to be used in disaster situations, like scaring off sea creatures in the event of a major toxic spill.

It has also been suggested a similar swarm of robots could be dispatched following a plane crash allowing them to trawl the ocean floor to search for the black box recorder at a much faster rate than current methods.

3D robot

The sea slug 3D printed robot. Image via Victoria Webster

So why is the robot based on a sea slug?

Aside from wanting to build an underwater biohybrid robot using a seaborne creature, the slug has many properties which make it ideal for adapting to the growing field of soft robotics.

Under the lead researcher of this project, Victoria Webster, the international research team found that the sea slug is a very durable creature at a cellular level making it capable of surviving huge variations in temperature.

Additionally, it was determined that the slug’s muscles are much more adaptable to different environments, compared with other mammal and avian species which only work in very specific settings.

Looking at why the team wanted to use animal-based muscle compared with standard robotics, Webster said: “One of the problems with traditional robotics, especially on the small scale, is that actuators – the units that provide movement – tend to be rigid.”

Organic muscles can learn movement

But by using the specific l2 muscle found in the slug’s mouth, it was found to achieve much better results than other muscles found on its body.

The final piece of the biohybrid puzzle is the slug’s ganglia, or nerve centre, which can be stimulated either chemically or electrically to contract the robot’s organic muscles, thereby controlling movement.

“With the ganglia,” Webster said, “the muscle is capable of much more complex movement, compared to using a manmade control, and it’s capable of learning.”

It’s now a matter of training the adapted ganglia to move the robot forward in response to one signal and backward in response to a second.

The end goal, Webster said, is to build a “living machine” or a robot that is completely organic with the next step being to use collagen from the slug’s skin to help create the scaffolding of the robot.

When this is achieved, researcher Ozan Akkus said, the integration of the muscle with its natural biological structure could make it nearly 1,000-times better than the current prototype.

Sea slug image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic