Modular Growing Mechanism with Multi-Axis Deformation

Plant cells expand and elongate. Their cumulative actuation defines organ morphing. Inspired by this modular transformability, this study proposes a modular concept for growing robots that will be able to grow by adding at their tip Transformable Modules (TMs). We provide a two- module implementation to evaluate the concept viability. We designed and characterized Shape-Retention Bellows (SRBs) that constitute the TM and are used to maintain the shape once the extension force is relaxed. We demonstrate module radial expansion and axial elongation in a straight and bent configuration (up to ∼4◦). This is the first concept of growing robots to enact the robot’s modularity and transformability for future deployment in distributed growing systems capable of acting in various scenarios.