The Nonlinear Dynamic Characteristic and Resonant Actuation of Bistable Composite Laminates with MFC

Bistable structures offer a straightforward means to achieve rapid shape reconfiguration in fields such as morphing aircraft design, flow control, and soft robotics, owing to their unique nonlinear characteristics and strong local stability behavior. Understanding the rapid switching mechanism between stable configurations of bistable laminates is crucial for engineering applications. This study investigates the nonlinear dynamic characteristics of bistable composite laminates with MFC (Macro Fiber Composite) actuators and proposes a resonant actuation method that minimizes energy consumption, enhancing the efficiency and controllability of the configuration switching. An analytical model is developed using the Rayleigh–Ritz method, with static and dynamic models based on the minimum potential energy principle and Hamiltonian principle, respectively. Additionally, considering the mechanical and electrical coupling effects of MFC and utilizing classical laminates theory, accurate geometric solutions for different configurations are obtained by incorporating the actual geometric deformation of the laminates. The nonlinear variation of the natural frequencies of bistable laminates is quantitatively described through backbone curves, revealing frequency hysteresis during frequency sweeps. The critical actuation conditions for bistable laminates actuated by MFC are determined through bifurcation diagrams obtained from forward frequency sweeps. To validate the accuracy of the analytical model under different conditions, comparisons are made with finite element models of bistable laminates created using ABAQUS software.