A Bilateral, Flexible Sensing Skin Integrated In Situ Self-Compensation for Multi-Modal Measurement of Morphing Wings

The utilization of morphing technology in aircraft represents a highly effective approach to improving aerodynamic performance and minimizing energy consumption. However, the deformation of morphing wings requires aerodynamic sensing technology to be versatile and deformable. Flexible electronic technology, characterized by its extreme flexibility and adaptability to irregular surfaces, can be used as a flexible sensing skin for morphing wings. Here, a bilateral, flexible sensing skin integrated in-situ self-compensation is proposed to address these challenges. The multiple sensing units for strain, temperature, and shear-stress are seamlessly integrated on both sides of a flexible substrate through a film modification process involving high-temperature annealing and a double-sided lithography process with laser peeling. Furthermore, a progressive compensation strategy is introduced to mitigate the interference of strain during deformation on the measurements of temperature and shear-stress units. The flexible sensing skin is designed with an "island-bridge" structure to allow for surface stretching. Experiments performed on a morphing wing demonstrate the superiority of the proposed design, suggesting significant potential for future aircraft testing applications.