Structure Design And Optimization Of Miniature Carbon Fiber Four-rotor UAV

Miniature four-rotor UAV are widely used in many industries due to their simple structure,easy to carry,versatility,low cost and so on.Two different configurations of miniature four-rotor UAVs are designed.The strength and stability analysis,structural optimization,static loading test and natural vibration analysis of the UAVs are carried out.The performance parameters and structure configurations are determined according to the design requirements of the miniature four-rotor UAV.The integration configuration and system components of power plant sub-system are determined.Three-dimensional structure models of the two UAV configurations are established.The finite element models for carbon fiber composite structure of the two UAV configurations are created.By means of numerical analysis,the strength and stability of the two structural finite element models are analyzed under different loading conditions.The structure strength is checked based on the strength criterion of maximum stress.The layer scheme and the spatial structure of the initial models are optimized according to the results of the numerical analysis,and the final optimal design scheme is obtained.The design requirements of strength and stability are met,and the structure weight of the two configuration UAVs is relatively lightest.The structure weight is decreased by 21%,and reduced to 108.6 g after model I is optimized.The structure weight is decreased by 28%,and reduced to 109.3 g after model II is optimized.The structures of the two configuration UAVs are produced according to the optimal structure scheme.The static loading test platform for the UAV structures is constructed based on the analysis of the actual loading conditions in flight.The static loading test is carried out and the test strain data is analyzed.Based on the comparison of test strain data and numerical simulation strain data,the numerical models of the UAV are corrected by stiffness parameter modification.The strength and stability of the experimental models are checked after the modification of the stiffness parameters.The reliability and validity of the UAV finite element models and the optimized design scheme are verified.The natural vibration analysis of the two configuration structures is carried to ensure that the resonance of the UAV structures will not occur in flight.The Model II structure resonates in test flight.The resonance phenomenon is eliminated by optimizing the arm structure of the model II,and the strength and stability of the new structure is checked.The assembly and system integration of the two configuration UAVs are completed,and the test flight of the UAVs is carried out successfully.