Fixed-wing aerial underwater vehicle and control method thereof

A control method for a fixed-wing aerial underwater vehicle, wherein the fixed-wing aerial underwater vehicle comprises a shell component, a flight component, and a pneumatic buoyancy component wherein the flight component comprises a fixed wing and a plurality of rotors, and the fixed wing and the rotor are all mounted on the shell component the pneumatic buoyancy component comprises an air bladder and an inflation and deflation portion, the air bladder is connected to the inflation and deflation portion, and the inflation and deflation portion is configured to inflate and deflate the air bladder;

• and the air bladder is installed on the shell component, a containing space is formed in the shell component, and the inflation and deflation portion is partially or entirely installed in the containing space, and the control method comprising following steps:
• flying out of water:
• opening a inflation solenoid valve to inflate an annular air bladder;
• when an air pressure in the annular air bladder reaches a set value, closing the inflation solenoid valve, then a waterproof brushless motor operating, and an auto-folding propeller rotating and unfolding;
• flying control:
• controlling an output current of the waterproof brushless motor by a four-in-one electronic speed controller to cause a rotational speed difference between a plurality of auto-folding propellers to achieve different motions;
• entering the water:
• turning off the waterproof brushless motor, the auto-folding propeller folding, opening a deflation solenoid valve to deflate the annular air bladder;
• when the air pressure in the annular air bladder reaches the set value, closing the deflation solenoid valve;
• and
• gliding underwater:
• controlling an opening and a closing of the inflation solenoid valve and the deflation solenoid valve to change a volume of the annular air bladder.