A self-sustained hydrogel oscillator, fueled by constant light, exhibits omnidirectional oscillation and powerful phototactic locomotion. Oscillations are widely found in living organisms to generate propulsion-based locomotion often driven by constant ambient conditions, such as phototactic movements. Such environment-powered and environment-directed locomotions may advance fully autonomous remotely steered robots. However, most man-made oscillations require nonconstant energy input and cannot perform environment-dictated movement. Here, we report a self-sustained soft oscillator that exhibits perpetual and untethered locomotion as a phototactic soft swimming robot, remotely fueled and steered by constant visible light. This particular out-of-equilibrium actuation arises from a self-shadowing–enabled negative feedback loop inherent in the dynamic light–material interactions, promoted by the fast and substantial volume change of the photoresponsive hydrogel. Our analytical model and governing equation unveil the oscillation mechanism and design principle with key parameters identified to tune the dynamics. On this autonomous oscillator platform, we establish a broadly applicable principle for converting a continuous input into a discontinuous output. The modular design can be customized to accommodate various forms of input energy and to generate diverse oscillatory behaviors. The hydrogel oscillator showcases agile life-like omnidirectional motion in the entire three-dimensional space with near-infinite degrees of freedom. The large force generated by the powerful and long-lasting oscillation can sufficiently overcome water damping and effectively self-propel away from a light source. Such a hydrogel oscillator–based all-soft swimming robot, named OsciBot, demonstrated high-speed and controllable phototactic locomotion. This autonomous robot is battery free, deployable, scalable, and integratable. Artificial phototaxis opens broad opportunities in maneuverable marine automated systems, miniaturized transportation, and solar sails.

中文翻译：

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基于自持水凝胶振荡器的柔光战术游泳者

一个自持的水凝胶振荡器，在持续不断的光的作用下，表现出全向振荡和强大的光战术运动。在活生物体中广泛发现振荡会产生基于推进力的运动，这些运动通常是由恒定的环境条件（例如光战术运动）驱动的。这种以环境为动力和以环境为导向的运动可以推动完全自主的远程操纵机器人。但是，大多数人为振荡需要不恒定的能量输入，并且不能执行环境指示的运动。在这里，我们报告了一个自持式软振荡器，作为光战术软游泳机器人，它显示出永久且不受限制的运动，并通过恒定的可见光进行远程加油和操纵。这种特殊的失衡驱动源于动态光-材料相互作用中固有的自阴影使能的负反馈回路，这是由于光敏水凝胶的体积发生快速而显着的变化而引起的。我们的分析模型和控制方程式揭示了振动机理和设计原理，并确定了可调节动力学的关键参数。在此自主振荡器平台上，我们建立了将连续输入转换为不连续输出的广泛适用原理。可以定制模块化设计，以适应各种形式的输入能量并生成各种振荡行为。水凝胶振荡器展示了在整个三维空间中具有近乎无限的自由度的，类似于生命的敏捷全向运动。强大而持久的振荡所产生的巨大力量可以充分克服水的阻尼，并有效地自我推离光源。这样的基于水凝胶振荡器的全软件游泳机器人OsciBot展示了高速且可控的光战术运动。这种自动机器人无需电池，可部署，可扩展且可集成。人工趋光性为可操纵的海洋自动化系统，小型化的运输和太阳帆打开了广阔的机遇。