Whereas it’d sound like a weapon of oceanic destruction within the fingers of Aquaman’s arch enemies, the brand new “stingraybot” from a group at ETH Zurich (the Federal Institute of Know-how of Switzerland) provides huge promise for surgical procedure, medical care, wildlife biology, robotics, and extra, because of muscular membranes of microbubbles.
At a mere 4 cm (1.6 inches) in width, the stingraybot swims utilizing the identical wavelike motions of the wing-like pectoral fins of actual stingrays. Much more remarkably, this tiny ichthyo-droid requires no cables or batteries for distant management or energy, as a result of ultrasound stimulation directs and flexes its micro-muscles.
Shi Z et al. Nature 2025
“Undulatory locomotion was an actual spotlight for us,” says group lead Daniel Ahmed, Professor of Acoustic Robotics for Life Sciences and Healthcare, and co-lead creator of the Nature paper “Ultrasound-driven programmable synthetic muscle tissues.” “It exhibits that we will use the microbubbles to realize not solely easy actions but in addition complicated patterns, like in a dwelling organism.”
Utilizing a microstructure mould, the group created silicone membranes with minute pores a mere tenth of millimeter deep and throughout (roughly the width of a human hair). As soon as submerged, these micropores entice air as microbubbles. By wirelessly beaming ultrasound on the membranes, the researchers may exactly manipulate them nearly instantaneously (inside milliseconds) to supply curving or wave motions in particular instructions.
The selection between curving and wave motions will depend on the association of the microbubbles. Arrays of equally-sized bubbles curve based on the amplitude of the ultrasound, whereas arrays of differently-sized bubbles will, at various frequencies, undulate.
Shi Z et al. Nature 2025
Whereas inflexible machines, automobiles, and robots product of unbending metal, plastic, and composite supplies are perfect for most up to date manufacturing, transport and fight wants, different duties require far larger flexibility, comparable to that which animals possess. Animals (together with people) depend on squishy flesh to present suppleness of motion and the power to squeeze into and thru tight areas with out damaging themselves or their environment.
Due to this fact, one of the crucial helpful functions of those ultrasound microbubbles muscle tissues is exact, mild manipulation for surgeons and biologists, as with the miniature gripper arm that Ahmed’s group has already developed. Co-lead creator Zhiyuan Zhang and colleagues used their gripper to seize a zebrafish larva with out inflicting harm. “It was fascinating to see simply how exactly but gently the gripper functioned,” says Zhang, one in all Ahmed’s former doctoral college students. “The larva swam away afterwards unhurt.”
Ultraschall und künstliche Muskeln
Utilizing microbubbles of various sizes, Ahmed’s group has additionally developed a tiny silicone surgical wheel-bot that they’ve efficiently remote-navigated by means of the coiling labyrinth of a pig’s intestines. “The gut is a very complicated atmosphere as a result of it’s slim, curved, and irregular,” says co-lead creator Zhan Shi. “It was, subsequently, notably spectacular that our wheel robotic was really in a position to transfer in there.”
As nicely, the group at ETH Zurich has created ultrasound-activated medication-delivery patches that may stick with curved surfaces together with various tissues, and has profitable examined exact dye-delivery in a tissue mannequin. If these developments proceed yielding advantages, Ahmed’s group hopes they’ll be capable to use stingraybots – probably swallowed inside dissolvable capsules – to ship remedy contained in the gastrointestinal tract with out the dangers and expense of surgical procedure.
Supply: ETH Zurich

