The focal lengths of the sub-eyes in a single-layer uniform curved compound eye are all the same, resulting in poor imaging quality for the compound eye. A non-uniform curved compound eye can effectively solve the problem of poor edge-imaging quality, however, it suffers from a large spherical aberration, and is unable to achieve zoom imaging. To solve these problems, a new type of aspherical artificial compound eye structure with variable focal length is proposed in this paper. The structure divides the surface compound eye into three fan-shaped areas with different focal lengths of the microlens in different areas, which allow the artificial compound eye to zoom in a certain range. The focal length and size of the microlens is determined by the area and the location of the microlens. The aspherical optimization of the microlens is calculated, and spherical aberration in each area is reduced to one percent of the initial value. Through simulation analysis, the designed artificial compound eye structure realizes focal length adjustment and effectively reduces the problem of the poor imaging quality of the curved compound eye edge. As a result, an aspherical artificial compound eye sample—where the number of sub-eyes is n = 61, and the diameter of the base is Φ = 8.66 mm—was prepared by using a molding method. Additionally, the mutual relationship between the eyes of the child was calibrated, and hence, a mathematical model for the simultaneous identification of multiple sub-eyes was established. This study set up an experimental artificial compound eye positioning system, and through a number of microlens capture target point settlement coordinates, achieved an error value of less than 10%.

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Aiming at the short endurance time of micro-rotor UAV, based on the analysis of the structural characteristics and the working principle of rotor UAV, a design scheme of foldable quad-rotor UAV based on c is proposed. The feasibility of cascade PID control method is verified by co-simulation and analysis with ADAMS dynamics simulation software and MATLAB. Through the comparison of the flight test results, the feasibility of the designed control algorithm for the attitude control of the foldable quadrotor UAV is verified. Flight test shows that the UAV can achieve foldable function on the basis of stable hovering and high flight, achieved good results.

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Numerical simulations of the unsteady aerodynamic characteristics of the flapping wing composite motion are performed. To avoid negative grid sizes arising with the use of a dynamic grid and leading to divergences in the simulation and to errors in the results, an overlapping nested grid is used for the flow field background, wing, and fuselage structure. The analysis is based on the Navier–Stokes equations (N-S) and the pressure–velocity coupling method, while spatial dispersion is handled using the second-order finite volume and the adaptive step size solving strategy. The lift and resistance generated by the wing for different combinations of flow velocity, flutter frequency and amplitude, and torsion angle are determined, and the aerodynamic efficiency and flow fields are compared to find the flapping parameters that give the best aerodynamic efficiency. The simulation results show that the aerodynamic lift of a flapping wing can be greatly increased by increasing the flapping frequency, while, for a fixed frequency, the lift can be further increased by increasing the flapping amplitude, although by only a small amount. Increasing the torsion angle in the flapping of the wing can also increase the lift, but the aerodynamic efficiency will be reduced if this angle is too large. Thus, an appropriate selection of flapping wing motion parameters can effectively increase the flight lift and improve the aerodynamic efficiency.