Mechanical structure design of UAV propeller blades with aerodynamic and structural optimization

With the growing use of agricultural UAVs, the aerodynamic efficiency and structural reliability of propeller blades directly determine their operational performance. This work focuses on the design and optimization of a modified NACA 4412 propeller blade with improved chord, twist, and thickness distribution, together with hybrid composite-aluminum construction. Finite Element Analysis (FEA) was conducted to evaluate both static stress and modal responses under realistic agricultural loads. The study demonstrates a hover efficiency of 7.8 g/W, a reduction of the maximum stress concentration factor to 1.3, and an extended fatigue life beyond 2000 hours. The innovation of this work lies in the detailed aerodynamic reshaping and structural reinforcement of the propeller blade, together with comprehensive dynamic and static analysis, which provides validated reference data for future UAV blade design.