Development of an Underwater Sliding Vehicle for Oceanographic Measurements

Underwater Sliding Vehicle (USV) has been developed in JAMSTEC since 1978. Purpose of the development is to provide a small and high performance towed vehicle for oceanographic measurement. USV is a kind of towed vehicle which moves in the vertical plane made by path of the tow ship and catenary of the tow cable. USV is not linked to the end of the tow cable,but moves along the tow cable. Thus USV does not need a large wing to overcome the hydrodynamic drag of tow cable,and can be made small and light weight. Prototype was made and tested in the Sagami Bay. Dimensions of the prototype are 0.6 m (length), 0.6 m (wing span),and 0.4 m (hight). Weight is about 5 kg in air. Analysis of the motion was also performed. Results of the calculation agreed well with those from the test,showing the maximum rate of surfacing greater than 2 m/sec and maximum rate of diving greater than 6 m/sec for 4 knots towing with use of 4 mm steel wire and hydrodynamic depressor which generates 35 kg depressing force at that speed.