- Allow the addition of incremental step-by-step improvements to 

 demonstrate progressively complex near-term advantages of improved 

 performance over existing systems and approaches. 



- Provide a basic system design which is adaptable to a variety of users. 



- Incorporate the use of analogic and symbolic controls and displays to 

 offer the operator a more familiar adaptation to the computer. 



- Be able to interface with the operator as a combination of direct 

 vehicle control and interactive and adaptive control. The machine does 

 not have to replace the man totally at all times, but the machine 

 should be capable of replacing the man during routine functions or for 

 operations such as automatic position holding, which are more easily 

 performed by automatic control. 



The vehicle (fig 1) is 9 feet long, 22 inches wide, and 22 inches high. 

 It weighs about 400 pounds in air, and has an operating depth of 2000 feet. A 

 long, narrow configuration was chosen to allow minimum drag in the forward 

 direction. By adapting a closed external skin, the speed could be increased 

 from its present measured 1.8 knots to a projected 5 knots. The "T"-shaped 

 frame, weighing only 10 pounds in water, is constructed of sealed, welded 

 aluminum tubing. An open-frame configuration has the advantage of allowing 

 the addition of payloads by simply strapping them onto the frame or by 

 lengthening the vehicle to accommodate 25 pounds of additional payload per 

 linear foot of extension. Syntactic foam blocks mounted on top of the frame 

 provide about 180 pounds of buoyancy. Two stern and one midships fixed- 

 mounted thrusters provide 3 degrees of freedom. The horizontal motion 

 thrusters are canted 15 degrees to provide a turning radius smaller than the 

 length of the vehicle. Each thruster is powered by commercially available 

 1/4-horsepower, 24-Vdc motors. The motor housings are oil -filled, pressure- 

 compensated units designed and fabricated at N0SC. Electrical interconnec- 

 tions are achieved by using oil-filled, pressure-compensated cables and 

 connectors. Four 7-inch-diameter, one-atmospheric-pressure aluminum bottles 

 are strapped to support brackets welded onto the main frame. The two 30-inch- 

 long bottles at the stern contain the basic microprocessor control electron- 

 ics, as well as the motor control electronics and switching relays which are 

 required for all configurations of the vehicle. The two 42-inch-long bottles 

 in front of the vehicle contain the sensor and communication system electron- 

 ics, which can be changed easily for various vehicle configurations. Two 

 3-inch-diameter, approximately 7-foot-long aluminum bottles containing the 

 main battery power pack are attached to brackets bolted to the lower portion 

 of the frame to provide a good center-of-gravity to center-of-buoyancy separa- 

 tion. The battery pack, which provides 26 and 14 Vdc, is constructed of a 

 series of Gates 2-volt, 25-ampere-hour rechargeable lead-acid batteries, 

 weighs about 77 pounds, and allows up to 1 hour of underwater vehicle dura- 

 tion. The lead-acid batteries could be replaced by more expensive non- 

 rechargeable lithium cells, which would deliver about five times the energy. 

 All metal parts exposed to saltwater are hard black-anodized aluminum. The 

 entire configuration is adjusted by trim weights to provide approximately 8 

 pounds of positive buoyancy. 



The basis of the vehicle control electronics is an Intel 8080 microproces- 

 sor on low-cost, commercially available (Prolog Corporation), fully tested 



