Surrogate-based pneumatic and aerodynamic allocation design optimization for flapping-wing micro air vehicles

Determining the mapping relationships between the bionic structures and aerodynamic characteristics of flapping-wing micro air vehicles (FWMAVs), therefore optimizing their comprehensive performances of pneumatic functions and maneuvering capabilities, poses a formidable challenge. In this work, a surrogate-based approach is proposed to tackle the pivotal challenges. Firstly, an experimental surrogate model is established for predicting the pneumatic performances of the flapping wings using multi-fidelity datasets, which incorporates an efficient global optimization strategy for the sample fill-in to enhance predictive precision while minimizing experimental costs. Secondly, to account for the intricate influences of control inputs on aerodynamic characteristics, comprehensive aerodynamic surrogate models are established to precisely anticipate pneumatic performances and torque allocations under different attitude control patterns. Thirdly, by elucidating the mapping relationships between bionic structures and aerodynamic performances, surrogate-based optimizations aim to identify optimal combinations of corresponding parameters of bionic structures, thereby enhancing the pneumatic and toque allocations of the FWMAV. The bionic structures achieve a maximum lift enhancement of 11.5% and at least a 5.4% improvement in torque generation through experimental validations. Based on the optimal outcomes of the bionic structure analysis of the FWMAV, a novel prototype family comprising three distinct sub-varieties is successfully fabricated. The findings of our research are hopefully to offer valuable insights for future FWMAV designs and make potential contributions to the advancement of standardized methodologies for evaluating their flight performances.