Robots are increasingly being constructed from soft, stretchy materials to make them more resilient and more compatible with living beings. However, powering them without traditional hard-edged circuit boards and motors is a challenge.
To get around using a motor in the manta-ray-inspired robot, Li and his colleagues made artificial fin muscles from a flexible polymer called dielectric elastomer. A silicone-encased lithium battery supplies a cyclic voltage that squeezes and releases that material, causing the muscles to bend up and down. This flaps the ray’s fins, made of a thin silicone film, so that it moves through the water.
The rest of the remotely controlled robot – which weighs 90 grams and has a wing span of 22 centimetres – is made of a silicone body and tail for steering. All components are transparent, except for the small battery pack and two electromagnets that help to manoeuvre the tail.
Read the full article here: https://www.newscientist.com/article/2126924-squishy-robotic-manta-ray-flaps-its-wings-to-spy-in-the-ocean/