In this project, we aim to establish a design theory as well as implementation methods for deformable robot mechanisms that can branch and change in shape, structure, and stiffness. As the first step in our research on this project, we present an initial prototype of a branched torus mechanism that uses an inflatable structure inspired by a nemertea proboscis. We develop a basic mechanical model of this proboscis structure, and we confirm the basic performance and effective functionality of the configuration experimentally using a real prototype, specifically, a deployable torus mechanism and a retractable torus mechanism with an incompressible fluid. In addition, as an expanded concept from the branched torus mechanism, robotic blood vessels that can have an active self-healing function are prototyped, and the basic performance of the actual prototype is confirmed through experiments.

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