ABSTRACT:
Negative stiffness honeycombs (NSHs) have multiple advantages compared to traditional honeycomb structures. These advantages include recoverable elastic buckling, shock absorption, and vibration isolation. As a result, NSHs have great potential in applications such as acoustic wave guiding, shape morphing, design of impact-protection devices and robotic grippers. In this paper, we present a design methodology for metamaterial consisting of negative stiffness beams assembled in a honeycomb structure. Based on analytical results, our methodology allows designing NSH mesostructures with predetermined buckling sequence. An NSH prototype was designed based on our algorithm and fabricated using a 3D printer with a nylon filament. The validity of our approach was experimentally verified by performing displacement controlled compression force measurements. Our methodology gives the ability to design NSH mesostructures with desired force-displacement characteristics.