Electrically-driven soft robots based on piezoelectric actuators may enable compact form factors and maneuverability in complex environments. In most prior work, piezoelectric actuators are used to control a single degree of freedom. In this work, the coordinated activation of five independent piezoelectric actuators, attached to a common metal foil, is used to implement inchworm-inspired crawling motion in a robot that is less than 0.5 mm thick. The motion is based on the control of its friction to the ground through the robot's shape, in which one end of the robot (depending on its shape) is anchored to the ground by static friction, while the rest of its body expands or contracts. A complete analytical model of the robot shape, which includes gravity, is developed to quantify the robot shape, friction, and displacement. After validation of the model by experiments, the robot's five actuators are collectively sequenced for inchworm-like forward and backward motion.

翻译：基于压电致动器的电驱动软体机器人可在复杂环境中实现紧凑构型与高机动性。以往研究多利用压电致动器控制单自由度运动，而本研究通过协调五个独立压电致动器（固定于共用金属箔片）的激活，实现了厚度不足0.5毫米的机器人仿尺蠖爬行运动。该运动机制通过机器人形状调控其与地面间的摩擦力——机器人一端（取决于其形状）依靠静摩擦力锚定于地面，其余身体部分进行伸缩运动。建立了包含重力效应的完整机器人形状分析模型，用以量化其形态、摩擦力与位移。经实验验证模型后，对机器人的五个致动器进行序列化编程，实现了仿尺蠖的前向与后向运动。