Three dimensional synthetic and real aperture sonar technologies with Doppler velocity log and small fiber-optic gyrocompass for autonomous underwater vehicle

摘要

The technologies could be expected a practical application of searching for submarine minerals, such as thermal vents a few meters high, to a depth of 3,000 meters. In order to develop exploration technologies for submarine resources, new sensor technology needs to be developed for use with autonomous underwater vehicles (AUV) or remotely operated vehicle (ROV). We have used an optic gyrocompass CDL Mini POS-II and a Doppler velocity log (DVL) RD WH300 for the research on three dimensional synthetic and real aperture sonar technologies. However, these sensors with pressure housing are too large to mount on autonomous underwater vehicle (AUV). So, in cooperation with IXBLUE and OceanWings, we created a small fiber-optic gyrocompass (FOG) with motion sensors based on IMU-50 and packed it in a small pressure housing with an outer diameter 112 mm and a length 295mm. We extracted a unit composed of three-axes angular velocity and three-axes velocity sensors and a serial interface from the IMU-50, and add it to a RS-232C converter board. Then we achieved the original software for measuring heading based on the true-north, roll, and pitch angles using the raw increment data from the small fiber-optic gyrocompass.