The invention belongs to the technical field of
underwater vehicle
navigation safety protection, and particularly relates to an
underwater vehicle protection device and method based on depth control. The device comprises a mechanical depth detection device, an
electromagnet, a weight, a power supply circuit and a detection circuit, wherein the mechanical depth detection device and the
electromagnet are arranged on a
pressure hull of an
underwater vehicle and contact with water outside the
underwater vehicle, the mechanical depth detection device and the
electromagnet are in series connection in the same power supply circuit, the electromagnet attracts the weight when the power supply circuit supplies power, and the power supply circuit is connected with a main control computer of the
underwater vehicle through the detection circuit. The method includes that when the
water pressure outside the
underwater vehicle reaches a trigger
water pressure, a normally-closed contact of the mechanical depth detection device is opened, the power supply circuit of the electromagnet is opened, without the attraction of the electromagnet, the weight can detach from the underwater vehicle, and a bigger positive
buoyancy and a bigger bow-buoying moment enable the underwater vehicle to float upwards automatically. The underwater vehicle protection device based on the depth detection is simple in structure, reliable in work and independent of a
control system of the underwater vehicle, and can effectively protect the safety of the underwater vehicle.