Shape-variable seals for pressure actuated cellular structures

Abstract

Sealing concepts allowing a large change of cross-sectional area are investigated. Shape variable seals are indispensable for the biologically inspired pressure actuated cellular structures (PACS), which can be utilized to develop energy efficient, lightweight and adaptive structures for diverse applications. The requirements regarding extensibility, stiffness and load capacity exceed the characteristics of state of the art solutions. This work focuses on the design of seals suitable for extensional deformations greater than 25 %. In a first step, a number of concepts are generated. Then the most suitable concept is chosen based on numerical characterization and experimental examination. The deformation supportive end cap (DSEC) yields satisfying results as it displays a stress optimized shape under maximum load, an energetically inexpensive bending-based deformation mechanism and utilizes the applied forces to support distortion. In the first real-life implementation of a double row PACS demonstrator, which contains DSEC, the proof of concept is demonstrated.