A Bioinspired Soft Swallowing Robot Based on Compliant Guiding Structure

From small unicellular organisms to large mammals, swallowing is an important way for them to interact with their external environment. The majority of these animals swallow their targets for the purpose of hunting, and some fish and amphibians protect their cubs from external injury by swallowing them. Thus, swallowing can produce an efficient capture, keep the integrity of targets, and provide effective protection for swallowed objects. Inspired by this, we propose a novel soft swallowing robot (SSR) capable of swallowing various objects that have different shapes and stiffnesses, protecting objects from squeeze and collision, and withstanding high temperature, which are enabled by a compliant guiding structure consisting of a double thin-walled capsule filled with fluid and a linearly movable traction body. In this article, we study the SSR supported by air and water, respectively; furthermore, we experimentally conclude that the working medium has a great influence on the inherent characteristics of the SSR. Our study helps lay the foundation for the research of soft robotic systems with swallowing characteristics, and the SSR is expected to enter the practical application field from the laboratory.