10 



2 . REMOTELY OPERATED VEHICLES 

 Four classes of ROVs have been identified in the course of this study: 



Tethered, Free-Swimming Vehicles : Powered and controlled through a 

 surface-connected cable. Self-propelled, capable of 3-dimensional maneuvering, 

 remote viewing through a closed-circuit television (CCTV) . 



Bottom-Crawling Vehicles : Powered and controlled through a surface-connected 

 cable. Self-propelled by drive wheels, capable only of maneuvering on the bottom, 

 or a structure, remote viewing through CCTV. 



Towed Vehicles : Powered and controlled through a surface-connected cable. 

 Propelled by surface ship, capable of maneuvering only forward and up/down by 

 cable winch. Remote viewing through CCTV. 



Untethered Vehicles : Self -powered, controlled by acoustic commands or 

 pre-set course. Self-propelled, capable of maneuvering in 3 dimensions. No 

 remote viewing capability. 



The primary vehicle of interest to this study is the tethered, free-swimming 

 vehicle. Consequently, this class is treated more comprehensively than are 

 the other three. While the term "tethered, free- swimming" is paradoxical, it 

 is used to differentiate this type vehicle from the bottom-crawling vehicles 

 which are tethered also, but capable of maneuvering only in contact with the 

 ocean bottom, or a structure. 



2.1 TETHERED, FREE- SWIMMING VEHICLES 



The pioneer vehicle in this class was Dimitri Rebikoff's 1953 POODLE, a modified 

 version of the diver transport vehicle PEGASUS. The primary components of 

 present day systems consist of: 1) a control/display console; 2) a power 

 source (ship's power or dedicated generator); 3) an umbilical cable (providing 

 power, control and data telemetry from surface-to-vehicle) ; 4) a launch/ 

 retrieval system and 5) the underwater vehicle itself (Plate 2.1). 



The growth of vehicles in this class has been impressive. In the 21 years 

 following the debut of Rebikoff's POODLE (1953-1974), 20 vehicles were constructed. 

 Seventeen (85 percent) of these were funded totally or partially by various 

 governments (U.S., France, England, Finland, Norway, USSR). From 1975 through 

 1978, 82 additional ROVs were added to the world inventory. Where industrial 

 users accounted for 15 percent of the 1974 market, they now (excluding special- 

 ized mine neutralization ROVs) account for 90 percent. The cause of this 

 remarkable growth is the burgeoning offshore oil and natural gas industry. 

 The year 1974 is significant because in that year the OPEC nations tripled 

 the price of oil. Consequently, offshore oil which theretofore was not 

 profitable to extract became profitable, and development proceeded accordingly. 



The pre-1974 ROVs were primarily, if not solely, dedicated to military and 

 scientific/research missions. Rebikoff's POODLE, for example, performed much 

 of its work in archeological exploration. The Soviet Union's MANTA 1.5; 

 Norway's SNURRE; Finland's PHOCAS and Scotland's ANGUS 01 were used in geological 

 and biological exploration. 



