Pattern Transformation Inspired Multifunctional Cylindrical Vessels with Programmable Stoma‐Shaped Biomimetic Openings

Pattern transformation in a periodic porous structure has inspired multifarious mechanical metamaterials/metastructures due to the induced unusual negative Poisson's ratio behavior of macroscopic materials. Recently, it has been leveraged to architect a variety of designable and multifunctional structural members. Inspired by this design methodology, a novel porous cylindrical shell, which is perforated by a large number of staggered openings, is constructed and investigated meticulously. A stable, anti-disturbed, and controllable waisted deformation of the architected cylindrical shell will be triggered under an axial compression. A stoma-shaped biomimetic hole and graded distribution of initial openings are proposed to ensure that the holes distributed throughout the shell can be closed up concurrently while the closed states of holes can be flexibly programmed. To explore the applications of such shells, a handy cylindrical vessel is elaborately designed and its multiple functions including reagent release, underwater sampling, and flow control are exhibited by experiments. The results reflected that the designed vessel can be facilitated with many advantages such as uniform release, quick action, easy actuation, and repeated usage. Moreover, it also might open a new avenue for metamaterials in the fields of biomedical engineering, underwater detection, fluid machinery, etc.