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Continuous leaping is an effective locomotion strategy for traversing cluttered and unstructured environments. However, achieving autonomous continuous leaping in soft machines remains challenging because it requires recyclable energy storage and release, reliable self-resetting for relaunch, aerial stability, and adaptability across diverse terrains. Here, we report a self-resetting soft ring jumper capable of autonomous, continuous, and stable horizontal leaping under constant infrared illumination. The jumper consists of a photothermally responsive liquid crystal elastomer ring integrated with a rigid V-shaped tail. Under illumination, the soft ring self-twists to store elastic energy while simultaneously inducing out-of-plane bending of the tail through geometric constraints imposed by the rigid tail. Once a critical threshold is reached, snapping of the rotating rigid tail against the ground launches the ring into the air. During flight, the ring autonomously untwists to recover its original shape and self-resets, enabling repeated cycles of energy storage, release, and relaunch. The snapping mechanism and full leaping dynamics are captured by combined static and dynamic Cosserat-rod models. By tuning geometric asymmetry and the center of mass, the jumper transitions among crawling, directional leaping, and vertical jumping. Optimized designs achieve vertical jumps exceeding 80 body heights and directional leaps over 3 body lengths. Beyond controlled motion on flat surfaces, the jumper demonstrates resilient multimodal locomotion across slopes, parallel hurdles, water–land interfaces, and diverse natural terrains including grass, sand, rocks, mulch, and water surfaces. This work can find potential applications in environmental navigation, swarm robotics, and unstructured terrain navigation. 

Mechanical metamaterials achieve multistep, programmable responses through sequential deformation driven by snapping instabilities, yet these sequences are typically governed by unavoidable imperfections, resulting in random and uncontrollable behavior. Here, we harness intra- and interlayer magnetic interactions coupled with elasticity to reprogram the ordering of sequential buckling instabilities in kirigami-inspired soft magnetic metamaterials. In single-layer systems, intralayer coupling among magnetized units produces random snapping sequences but generates strongly nonlinear-spiked force-displacement responses with pronounced hysteresis, in contrast to the simultaneous buckling of unmagnetized sheets. In multilayer assemblies, interlayer magnetic interactions trigger chain reaction–like propagation, transforming randomness into robust, directional snapping across structures. This mechanism establishes a paradigm for deterministic, multistep mechanical responses without continuously applied fields and opens avenues for adaptive materials in energy dissipation, waveguiding, reconfigurable soft robotics, and biomedical devices. 

Multistable metastructures can switch between multiple stable configurations without requiring locking forces. However, their potential for creating reconfigurable robots—metabots—capable of adapting to changing environments remains largely unexplored. Here, we report harnessing developable surface–based multistable thin-shell metastructures with high reconfigurability for adaptive manipulation and locomotion. These multistable metastructures are constructed by cutting and bonding thin polymer sheets with patterned cutouts, enabling programmable prestored elastic energy. A single unit achieves up to 20 stable configurations, while a four-unit assembly yields 256 reconfigured states, through simple folding of dynamic virtual creases. When integrated with thin sheet–based, multiresponsive soft actuators, these metastructures become highly adaptive metabots, including universal, noninvasive bistable soft grippers; magnetic multigait jumpers; and dual-responsive crawlers powered by magnetic and electroactive actuation. These systems exhibit high adaptability and maneuverability, capable of navigating complex terrains and confined environments via on-demand shape transformations, paving the way for energy-efficient, reconfigurable soft robotic platforms. 

Shape-shifting structures can transform and recover their shapes in response to external stimuli, but they often lack programmable, clock-like control over spatiotemporal deformation and motion, especially after stimuli are removed. Achieving autonomous, time-regulated spatiotemporal motion remains a grand challenge. Here, we present an autonomous delayed-jumping metashell that integrates viscoelastic materials with monostable architected structures to address this limitation. The metashell with tunable prestored elastic energy features an internal time clock enabling programmable autonomous delayed snapping and jumping after actuation removal. The delay spans from seconds to 2.4 d, with jumping heights decreasing from over 9 to 0.5 body heights. We demonstrate its utility in autonomous explosive seed dispersal devices, achieving wide-area omnidirectional distribution with high survival rates. This strategy paves the way for creating autonomous spatiotemporal shape-shifting structures with broad applications in robotics, morphing matter, ecology, and intelligent systems. 

We explore a new design strategy of leveraging kinematic bifurcation in creating origami/kirigami-based three-dimensional (3D) hierarchical, reconfigurable, mechanical metamaterials with tunable mechanical responses. We start from constructing three basic, thick, panel-based structural units composed of 4, 6 and 8 rigidly rotatable cubes in close-looped connections. They are modelled, respectively, as 4R, 6R and 8R (R stands for revolute joint) spatial looped kinematic mechanisms, and are used to create a library of reconfigurable hierarchical building blocks that exhibit kinematic bifurcations. We analytically investigate their reconfiguration kinematics and predict the occurrence and locations of kinematic bifurcations through a trial-correction modelling method. These building blocks are tessellated in 3D to create various 3D bifurcated hierarchical mechanical metamaterials that preserve the kinematic bifurcations in their building blocks to reconfigure into different 3D architectures. By combining the kinematics and considering the elastic torsional energy stored in the folds, we develop the geometric mechanics to predict their tunable anisotropic Poisson’s ratios and stiffnesses. We find that kinematic bifurcation can significantly effect mechanical responses, including changing the sign of Poisson’s ratios from negative to positive beyond bifurcation, tuning the anisotropy, and overcoming the polarity of structural stiffness and enhancing the number of deformation paths with more reconfigured shapes. This article is part of the theme issue ‘Origami/Kirigami-inspired structures: from fundamentals to applications’. 

Shape-morphing capabilities are crucial for enabling multifunctionality in both biological and artificial systems. Various strategies for shape morphing have been proposed for applications in metamaterials and robotics. However, few of these approaches have achieved the ability to seamlessly transform into a multitude of volumetric shapes post-fabrication using a relatively simple actuation and control mechanism. Taking inspiration from thick origami and hierarchies in nature, we present a hierarchical construction method based on polyhedrons to create an extensive library of compact origami metastructures. We show that a single hierarchical origami structure can autonomously adapt to over 10000 versatile architectural configurations, achieved with the utilization of fewer than 3 actuation degrees of freedom and employing simple transition kinematics. We uncover the fundamental principles governing theses shape transformation through theoretical models. Furthermore, we also demonstrate the wide-ranging potential applications of these transformable hierarchical structures. These include their uses as untethered and autonomous robotic transformers capable of various gait-shifting and multidirectional locomotion, as well as rapidly self-deployable and self-reconfigurable architecture, exemplifying its scalability up to the meter scale. Lastly, we introduce the concept of multitask reconfigurable and deployable space robots and habitats, showcasing the adaptability and versatility of these metastructures. 

Manta rays use wing-like pectoral fins for intriguing oscillatory swimming. It provides rich inspiration for designing potentially fast, efficient, and maneuverable soft swimming robots, which, however, have yet to be realized. It remains a grand challenge to combine fast speed, high efficiency, and high maneuverability in a single soft swimmer while using simple actuation and control. Here, we report leveraging spontaneous snapping stroke in the monostable flapping wing of a manta-like soft swimmer to address the challenge. The monostable wing is pneumatically actuated to instantaneously snap through to stroke down, and upon deflation, it will spontaneously stroke up by snapping back to its initial state, driven by elastic restoring force, without consuming additional energy. This largely simplifies designs, actuation, and control for achieving a record-high speed of 6.8 body length per second, high energy efficiency, and high maneuverability and collision resilience in navigating through underwater unstructured environments with obstacles by simply tuning single-input actuation frequencies. 

Fluid‐driven artificial muscles exhibit a behavior similar to biological muscles which makes them attractive as soft actuators for wearable assistive robots. However, state‐of‐the‐art fluidic systems typically face challenges to meet the multifaceted needs of soft wearable robots. First, soft robots are usually constrained to tethered pressure sources or bulky configurations based on flow control valves for delivery and control of high assistive forces. Second, although some soft robots exhibit untethered operation, they are significantly limited to low force capabilities. Herein, an electrohydraulic actuation system that enables both untethered and high‐force soft wearable robots is presented. This solution is achieved through a twofold design approach. First, a simplified direct‐drive actuation paradigm composed of motor, gear‐pump, and hydraulic artificial muscle (HAM) is proposed, which allows for a compact and lightweight (1.6 kg) valveless design. Second, a fluidic engine composed of a high‐torque motor with a custom‐designed gear pump is created, which is capable of generating high pressure (up to 0.75 MPa) to drive the HAM in delivering high forces (580 N). Experimental results show that the developed fluidic engine significantly outperforms state‐of‐the‐art systems in mechanical efficiency and suggest opportunities for effective deployment in soft wearable robots for human assistance. 

Soft shape-shifting materials offer enhanced adaptability in shape-governed properties and functionalities. However, once morphed, they struggle to reprogram their shapes and simultaneously bear loads for fulfilling multifunctionalities. Here, we report a dynamic spatiotemporal shape-shifting kirigami dome metasheet with high deformability and stiffness that responds rapidly to dynamically changing magnetic fields. The magnetic kirigami dome exhibits over twice higher doming height and 1.5 times larger bending curvature, as well as sevenfold enhanced structural stiffness compared to its continuous counterpart without cuts. The metasheet achieves omnidirectional doming and multimodal translational and rotational wave-like shape-shifting, quickly responding to changing magnetic fields within 2 milliseconds. Using the dynamic shape-shifting and adaptive interactions with objects, we demonstrate its applications in voxelated dynamic displays and remote magnetic multimodal directional and rotary manipulation of nonmagnetic objects without grasping. It shows high-load transportation ability of over 40 times its own weight, as well as versatility in handling objects of different materials (liquid and solid), sizes, shapes, and weights.