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2.4.5 Naval Ocean Systems Center 



With funding derived from the U.S. Geological Survey, NOSC is presently 

 developing a robot test-bed, untethered submersible to allow demonstration of 

 new, improved ROV system technology. The submersible, which is 2.2m (9 ft) long, 

 about 20 inches high and 20 inches wide, has a modular construction which 

 allows expansions to accommodate additional payloads and new sensor systems 

 as the technology for those systems becomes feasible to demonstrate. The 

 vehicle is designed to follow a set of predetermined program tracks such as 

 a parallel-path search or a figure-8 demonstration run. In this mode of 

 operation, the vehicle is programmed via a computer console and an umbilical 

 cable which is disconnected after the initial preprogramming phase. The 

 vehicle is then allowed to follow this course until its mission is complete. 

 A microprocessor is used to compare programmed altitude, heading, depth, and 

 run sequence input data with measured data coming from an on-board altimeter, 

 gyrocompass, depth sensor, and clock, respectively . The microprocessor generates 

 digital error signals between the programmed values and the measured values, 

 and issues error signals to the appropriate motor controllers. The motor 

 controllers then power the DC motors which directly drive the propellers 

 from a separate 24V battery supply. If emergency arises, there are automatic 

 procedures which allow the vehicle to turn on an emergency beacon which 

 shuts off all thrusters and is recovered at the surface. 



After initial tests with this mode of operation, other methods of vehicle 

 command control and communications will be demonstrated. Communication with 

 the vehicle while it is underwater will eventually be incorporated by means 

 of an acoustic or fiber optics link from the surface. The same programmable 

 controls used for setting up initialization of the vehicle through the hard 

 wire link on the surface will then be incorporated into this real time control 

 system, together with some editing commands. The vehicle would then be able 

 to (a) alter its preprogrammed mission sequence, and/or (b) respond to direct 

 control commands from the surface. 



The end result will be a system which is not limited by cable drag and cable- 

 handling problems and one which should autonomously perform rudimentary 

 tasks without direct operator control. At present vehicle power is obtained 

 from sealed lead- acid batteries. 



In-water tests of the vehicle were conducted in October 1978. Future plans 



for 1979 include: addition of a flux-gate updated gyro compass with a 12-bit 



A/D conversion accuracy; visual, colorgraphics display of programmed tracks; 



development of a magnetic pipeline following capability, and development of 



a fiber optics communication link to allow the use of both real-time command 



and control together with wide bandwidth data sensors such as TV and side scanning 



sonar. 



2.4.5 University of New Hampshire 



The objective of the University of New Hampshire's (UNH) program is to develop 

 an underwater vehicle which will automatically follow a pipeline using an 

 acoustic array as the sensing element. The vehicle has twin electric thrusters 

 on three axes to allow navigation in any direction v;ithout preferred orientation. 



