Abstract:The landing-gear retracting and releasing system and braking system of UAV plays a crucial role in the process of takeoff, landing, and braking of UAVs. Electrostatic hydraulic systems not only retain the advantages of traditional hydraulic systems, but also have the advantages of electric actuation. According to the working principle of the electro-hydrostatic actuator, an electro-hydrostatic system integrating the landing-gear retracting and releasing and braking functions of unmanned aerial vehicles is designed. The improved PID control method is applied to the landing-gear retracting and releasing function, and two fuzzy PID control methods are designed to apply to the anti-skid braking function. On this basis, a co-simulation based on AMESim and MATLAB/Simulink is conducted to verify the system performance, Finally, the simulation results are compared and analyzed. The results show that the designed control method can normally complete the landing-gear retracting and releasing and braking of unmanned aerial vehicles, and the control effect is good.