Buoyancy adjusting device and application

The invention discloses a buoyancy adjusting device and application, and belongs to the field of AUV heavy buoyancy adjustment. Comprising a power module, a self-locking module, a connecting module, a water suction and drainage module and a fixing module. Power is provided for the buoyancy adjusting device through the power module, and buoyancy adjusting control is achieved. The limiting position is locked through the self-locking module, and the normal operation state of the aircraft in the locking state is guaranteed; the power module is connected with the water suction and drainage module through the connecting module to realize power transmission; the action of water absorption or water drainage is completed through the water absorption and drainage module, and then buoyancy is adjusted by changing gravity; and the fixing module is used for fixedly connecting other modules with the aircraft. According to the buoyancy adjusting device, the net buoyancy of the AUV can be accurately adjusted within a certain