Buoyancy adjusting device with emergency floating function and buoyancy adjusting method thereof

The invention discloses a buoyancy adjusting device with an emergency floating function and a buoyancy adjusting method of the buoyancy adjusting device. A sliding guide rail is fixed to the bottom of a sealed cabin, and the sliding guide rail and the n sliding blocks form a sliding pair. The end part fixed plate is fixed on the sliding guide rail; the end part movable plate and the (n-1) movable frames are fixed with the n sliding blocks one by one; the adjacent movable frames, the end fixing plates and the adjacent movable frames, and the end movable plates and the adjacent movable frames are fixedly connected through telescopic rod sets. One end of an inner oil bag is fixed with the end fixed plate, and the other end is fixed with the end movable plate; and the pipeline is communicated with the inner oil bag and the outer oil bag. Each shrinkage rod of a shrinkage rod group is made of an electroactive polymer material. Buoyancy adjustment is achieved only through the telescopic rod, the response time is sh