Programmable Multi-stable Structure Based on Cosine Beam

Abstract

Mechanical metamaterials with multi-stable properties are an emerging field of interest. In this paper, we present a novel 3D bi-stable cell element with negative stiffness characteristics designed based on a cosine-curved beam. Static compression simulations were performed for the single-cell model and the series model. Using “E” and “F” states as programming units, five array models were designed to analyze the stiffness variation rules. Dynamic simulations were conducted to compare the energy absorption rate and collision force of the model with variable stiffness. The conclusion shows that the structure has multi-stable and negative stiffness characteristics, and its stiffness can be adjusted in the range of 113.0 to 197.6 N/mm. Additionally, the energy absorption rate can be adjusted in the range of 8% to 65%. This study has made the structure configurable after manufacturing, breaking through the application limitations of predefined objects, and broadening its application prospects.