A submillimeter-scale, soft continuum robot navigates through highly constrained environments by steering based on magnetic actuation. Small-scale soft continuum robots capable of active steering and navigation in a remotely controllable manner hold great promise in diverse areas, particularly in medical applications. Existing continuum robots, however, are often limited to millimeter or centimeter scales due to miniaturization challenges inherent in conventional actuation mechanisms, such as pulling mechanical wires, inflating pneumatic or hydraulic chambers, or embedding rigid magnets for manipulation. In addition, the friction experienced by the continuum robots during navigation poses another challenge for their applications. Here, we present a submillimeter-scale, self-lubricating soft continuum robot with omnidirectional steering and navigating capabilities based on magnetic actuation, which are enabled by programming ferromagnetic domains in its soft body while growing hydrogel skin on its surface. The robot’s body, composed of a homogeneous continuum of a soft polymer matrix with uniformly dispersed ferromagnetic microparticles, can be miniaturized below a few hundreds of micrometers in diameter, and the hydrogel skin reduces the friction by more than 10 times. We demonstrate the capability of navigating through complex and constrained environments, such as a tortuous cerebrovascular phantom with multiple aneurysms. We further demonstrate additional functionalities, such as steerable laser delivery through a functional core incorporated in the robot’s body. Given their compact, self-contained actuation and intuitive manipulation, our ferromagnetic soft continuum robots may open avenues to minimally invasive robotic surgery for previously inaccessible lesions, thereby addressing challenges and unmet needs in healthcare.

中文翻译：

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铁磁软连续体机器人

亚毫米级的软连续体机器人通过基于磁致动的转向来在高度受限的环境中导航。能够以远程可控方式主动进行转向和导航的小型软连续机器人在各个领域，特别是在医疗应用中，都具有广阔的前景。然而，由于常规致动机构固有的小型化挑战，例如拉动机械线，给气动或液压腔室充气，或嵌入用于操作的刚性磁体，因此，现有的连续体机器人通常限于毫米或厘米级。另外，连续机器人在导航过程中所经历的摩擦对其应用提出了另一挑战。在这里，我们提出了一个亚毫米尺度，具有基于磁驱动的全向转向和导航功能的自润滑软连续体机器人，该机器人可通过在其软体中编程铁磁畴并在其表面上生长水凝胶皮肤的方式来启用该功能。机器人的身体由柔软的聚合物基体的均匀连续体和均匀分布的铁磁微粒组成，直径小于几百微米时可以小型化，水凝胶表皮的摩擦力可降低10倍以上。我们展示了在复杂且受约束的环境中导航的能力，例如具有多个动脉瘤的曲折脑血管体模。我们进一步演示了其他功能，例如通过集成在机器人身体中的功能核心进行可控激光传输。考虑到它们的紧凑性，