The invention relates to a compact type high-propelling-ratio
underwater robot comprising a
robot main body, propulsion devices, an illumination device and a power supply device. A first seal ring is arranged between a hemispherical cover and a
flange, a second seal ring is arranged between the
flange and a cabin body, and a gland, the hemispherical cover, the
flange and the cabin body are fixed into a sealed whole through bolts, so that the seal performance of the cabin body of the
robot is guaranteed. A shell of the vertical propulsion device is adopted to integrate a horizontal
propeller, a vertical
propeller and the illumination device, the overall structures of the propellers are more compact, so that the size of the
underwater robot is smaller, and additionally, through a
handle design on the cabin body, much convenience is achieved. A novel ROVMAKER
underwater motor is adopted, so that the submerged depth is larger,
corrosion resistant capacity is very high, safety and reliability are achieved. Meanwhile, because the compact type high-propelling-ratio
underwater robot is small in size and good in seal performance, the overall structure of the compact type high-propelling-ratio
underwater robot has the advantages of small size, good airtightness and high propelling ratio.