Miniaturized Untethered Soft Robots Using Hydrogel-based Soft Voxel Actuators*

Current soft actuators rely on additional hardware such as pumps, high voltage supplies, light generation sources and magnetic field generators for their operation. These components resist miniaturization and embedding them into small-scale soft robots would be challenging. This limits their mobile applications where the entire system needs to be untethered especially in hyper-redundant robots where a high number of actuators are needed. Here, we introduce miniature and untethered robots made of soft voxel actuators (SVAs) – an active voxel using stimuli-responsive hydrogels actuated by electrical currents through Joule heating. SVAs weighing only 100 mg require small footprint microcontrollers for their operation which can be embedded in the robotic system. We have demonstrated the advantages of hydrogel-based SVAs through a hyper-redundant manipulator with 16 actuators and an untethered miniature robot for underwater mobile applications.

当前的软驱动器在运行时依赖于诸如泵、高压电源、光源以及磁场发生器等附加硬件。这些组件难以小型化，并且将它们嵌入小型软机器人中颇具挑战性。这限制了它们在移动应用中的使用，因为整个系统需要不受束缚，特别是在需要大量驱动器的超冗余机器人中。在此，我们介绍由软体素驱动器（SVA）制成的微型无束缚机器人——一种利用通过焦耳热产生电流驱动的刺激响应水凝胶的活性体素。仅重100毫克的SVA在运行时仅需占用空间小的微控制器，这些微控制器可嵌入机器人系统中。我们通过一个具有16个驱动器的超冗余操纵器以及一个用于水下移动应用的无束缚微型机器人，展示了基于水凝胶的SVA的优势。