pulsating jellyfish robots can pick up and vacuum ocean trash using artificial muscles

Cleaning the ocean with jellyfish robots

Making the ocean free from trash one day is a vision that roboticists at the Max Planck Institute for Intelligent Systems in Stuttgart plan to carry out in real life. To do that, they need help. The researchers tap the assistance of the versatile and flexible jellyfish to drive their vision and design forward, culminating in a smack of jellyfish robots that can dive deep into the ocean bed and float up to the surface, carrying the trash they capture under the sea. Named Jellyfish-Bot, the almost noise-free prototype can trap objects underneath its body without physical contact, enabling safe interactions with delicate marine life such as coral reefs.

‘When a jellyfish swims upwards, it can trap objects along its path as it creates currents around its body. In this way, it can also collect nutrients. Our robot, too, circulates the water around it. This function is useful in collecting objects such as waste particles. It can then transport the litter to the surface, where it can later be recycled. It is also able to collect fragile biological samples such as fish eggs. Meanwhile, there is no negative impact on the surrounding environment. The interaction with aquatic species is gentle and nearly noise-free,’ says Tianlu Wang, a postdoc in the Physical Intelligence Department at MPI-IS and the first author of the research.

images courtesy of the research team (Tianlu Wang, Hyeong-Joon Joo, Shanyuan Song, Wenqi Hu, Christoph Keplinger, Metin Sitti)

Creating artificial muscles with air cushions

The roboticists at the Max Planck Institute for Intelligent Systems have built their jellyfish robots using artificial muscles, or electrohydraulic actuators, in which the electricity that flows powers the robot and mechanism. They enclose these artificial muscles with air cushions and rigid components to stabilize the robot and make it waterproof. Through this, any high voltage contact in the water is prevented, enabling a safe interaction.

The roboticists state that there is a power supply that periodically provides electricity through the thin wires that cause the muscles to contract and expand like a living jellyfish. Recently, they tested their jellyfish robot in the pond of the Max Planck Stuttgart campus. They attached a buoyancy unit at the top of the robot and a battery and microcontroller to the bottom. They were successful in steering the robot, and the researchers are set to look into directing the wireless robot to change course and swim the other way for further tests.

the almost noise-free prototype can trap objects underneath its body without physical contact

Wireless ocean-cleaning devices in the future

Co-author Hyeong-Joon Joo from the Robotic Materials Department states that the researchers have also delved into how they could operate a collective of several robots. ‘For instance, we took two robots and let them pick up a mask, which is very difficult for a single robot. Two robots can also cooperate in carrying heavy loads. However, at this point, our Jellyfish-Bot needs a wire. This is a drawback if we really want to use it one day in the ocean,’ he says.

The roboticists think that wires powering robots may soon be a thing of the past. ‘We aim to develop wireless robots. Luckily, we have achieved the first step towards this goal. We have incorporated all the functional modules like the battery and wireless communication parts so as to enable future wireless manipulation,’ says Tianlu Wang. Soon, the team will create more jellyfish-inspired, energy-efficient, and nearly noise-free ocean-cleaning robots.

the jellyfish robots use artificial muscles in which the electricity that flows powers their mechanism