Design and analysis of a tri-stable structure based on bi-stable laminates

This paper develops a tri-stable structure that consists of four bi-stable rectangular laminates. The tri-stable structure can exhibit three different stable geometric configurations: plane, concave, and convex configurations. The structure can also be snapped between the various states. The design and fabrication methods of the tri-stable structure using bi-stable rectangular laminates are presented. A two-step finite element simulation is performed to predict the critical load to snap the tri-stable structure and to capture the snap-through process. The predicted curvatures and the critical loads from the finite element analysis show a high agreement with the experimental results. The tri-stable structures and the proposed two-step method should be instructive to design and construct the multi-stable structures and to understand their snap-through process.