Design and Snap-Through Behaviors of Shape Memory Polymer Based Multistable Mesh Structure

A design of shape memory polymer based multistable mesh structures is presented. Based on the curved beam bistable unit cell, the snap-through behavior, energy absorption, and the effects of geometric parameters (the thickness, width, and height of the curved beam) on the snap-through behavior have been studied. The finite element simulation results show that thermally activated SMP can enable the proposed multistable mesh structure to achieve steady-state transitions. The shape memory snapping experiment of the unit cell also validates the effectiveness of the finite element simulation. With the increase of these geometric parameters, the snap-through load and energy absorption of the unit cell increase, and the influence of the thickness is most significant. Results show that snap-through transitions of the proposed structures can be further tuned by changing the thickness of edge support of the curved beam unit cell, leading to the success or failure of shape memory snapping behavior. Based on these findings, a novel design for a smart tunable surface is proposed based on shape memory saddle-shaped curved beam unit cells and the feasibility of this design is illustrated through two examples of “ICMSD” and “Heart” shaped smart tunable surface. This research will provide a potentially feasible approach for designing smart multistable mesh structures.