Ultrasound-Driven Programmable Artificial Muscles

ABSTRACT Despite their promise for technological and medical innovations, the advancement of artificial muscles faces challenges in dynamic programmability, wireless control, scalability, and responsiveness. Ultrasound offers a promising yet underutilized solution, providing effective and robust actuation. We introduce an innovative design paradigm for soft artificial muscles, utilizing tens of thousands of resonant microbubbles for targeted activation, enabling a wide range of programmable motions. We developed a comprehensive theoretical model and conducted various applications: from actuating soft grippers and powering centimeter-scale biomimetic stingraybots for propulsion to demonstrating the multimodal shape transformation of a functional surface and equipping static objects with transformative robotic skins for mobility. Our approach is marked by its compactness, high force intensity, rapid responsiveness, and lightweightness. The customizable, scalable design of our artificial muscles offers both immediate and long-term impact on robotics, wearable technology, haptics, prosthetic development, and the development of avant-garde biomedical devices like soft surgical tools. One-Sentence Summary We introduced a first-of-its-kind, programmable artificial muscle using ultrasound-activated microbubbles, providing a compact, responsive, and scalable solution.