Soft miniature robots with multimodal locomotion

Untethered miniature robots can facilitate access to and inspection of narrow, re-mote and unexplored environments. However, restricted mobility of miniature robots may hinder the realization of targeted applications in highly unstructured landscapes. Here we report untethered, amphibious, millimeter-scale soft robots capable of mul-tiple modes of locomotion to move across liquid and solid unstructured terrains. Ac-tuated by locomotion mode-specific external magnetic fields, the magneto-elastic sheet-shaped robots with a pre-programmed magnetization profile and hydrophobic surface can swim inside and on the surface of liquids, climb liquid menisci, roll, walk on ground, jump directionally over obstacles, and crawl within narrow spaces. Such robots can reversibly transit from the surface to the bulk of a liquid, and from a liq-uid surface to rigid ground. They can additionally execute pick-and-place tasks and deformation-triggered release of cargos. Such minimalist, programmable and versa-tile soft robots could enable applications in environmental monitoring and minimally invasive medical operations inside the human body.