Sub-millimeter untethered locomoting robots hold promise to radically change multiple areas of human activity such as microfabrication/assembly or health care. To overcome the associated hurdles of such a degree of robot miniaturization, radically new approaches are being adopted, often relying on soft actuating polymeric materials. Here, we present light-driven, crawling microrobots that locomote by a single degree of freedom actuation of their light-responsive tail section. The direction of locomotion is dictated by the robot body design and independent of the spatial modulation of the light stimuli, allowing simultaneous multidirectional motion of multiple robots. Moreover, we present a method for steering such robots by reversibly deforming their front section, using ultraviolet (UV) light as a trigger. The deformation dictates the robot locomotion, performing right- or left-hand turning when the UV is turned on or off respectively. The robots' motion and navigation are not coupled to the position of the light sources, which enables simultaneous locomotion of multiple robots, steering of robots and brings about flexibility with the methods to deliver the light to the place of robot operation.

中文翻译：

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光响应水凝胶微型爬行器，通过空间均匀照明提供动力和转向。


亚毫米级无束缚运动机器人有望从根本上改变人类活动的多个领域，例如微加工/装配或医疗保健。为了克服这种程度的机器人小型化的相关障碍，人们正在采用全新的方法，通常依赖于软驱动聚合物材料。在这里，我们展示了光驱动的爬行微型机器人，它们通过光响应尾部的单自由度驱动来移动。运动方向由机器人主体设计决定，并且与光刺激的空间调制无关，从而允许多个机器人同时进行多向运动。此外，我们提出了一种通过使用紫外线 (UV) 光作为触发器，使机器人前部可逆变形来操纵此类机器人的方法。变形决定了机器人的运动，当 UV 打开或关闭时分别执行右转或左转。机器人的运动和导航与光源的位置无关，这使得多个机器人能够同时运动、机器人转向，并为将光线传送到机器人操作地点的方法带来了灵活性。