Toward a deeper understanding of layer jamming structures

Abstract

Layer jamming structures (LJSs) are variable-stiffness elements used in soft robotics to enhance load-bearing capacities. The complexity of interactions within these structures has impeded the development of a comprehensive model, often making LJS design reliant on empirical experience. Existing models primarily focus on straight beams under specific conditions, thus exhibiting limited applicability. To address these challenges, we developed a novel model that specifically investigates the bending deformation characteristics of LJS beams. Through finite element analysis, we analyzed the stress distribution and stress increments during bending and established a relationship between stress and external loads. From this foundation, we derived a governing deformation equation that is applicable to all LJS beams and can address the issue of large deformation under complex loading conditions through an iterative algorithm. Our model was validated experimentally and proven to be highly accurate in predicting the effects of layer thickness, hydrostatic pressure, and cyclic loading. This research substantially advances the understanding of LJS mechanical behavior, laying the groundwork for the development of sophisticated applications and structural designs in this rapidly evolving field.

Graphical abstract

Keywords

layer jamming structure / variable stiffness / beam theory / bending stiffness

RIGHTS & PERMISSIONS

Higher Education Press