Energy-Assisted Compliant Switching of Dual-Mode Morphing Wing With Metamorphic Mechanism

The concept of morphing wings is often incorporated in the design of highly adaptive aircraft. However, the design of dual-mode morphing wing and the research of mode switching method remain insufficiently developed. This article presents a novel dual-mode morphing wing based on the characteristics of multiple modes of metamorphic mechanism. Through the combination of basic 4R mechanisms, we designed a class of line symmetry Bricard mechanisms. A novel self-coupling joint is developed to enable compliant switching between different modes without new actuator. Based on the energy change during movement, we propose an energy-assisted method to realize the mode switching. Ultimately, we constructed a prototype aircraft with two modes: variable anhedral angle for enhanced maneuverability and variable sweep angle for better aerodynamic efficiency. The mode switching experiment shows that the motion state of the joint changes compliantly during the mode switching. The experiments show that the morphing wing can change the anhedral angle (7°–12°) and sweep angle (15°–30°), and can change the mode with the help of flight conditions. The aircraft can fly successfully in both modes, which shows the superiority of the design method. The findings of this study hold significant potential for the design of morphing wings in highly adaptive aircraft.