REAL-TIME CONTROL. The lack of real-time control during the TRANSDEC tests 

 was not as serious a problem as expected, particularly since the surfaced 

 vehicle experienced a definite water current caused by a relatively strong 

 westerly wind. The current was rather constant, and it was observed that the 

 vehicle could actually be programmed to return repeatedly to the side of the 

 tank. However, in most circumstances, a lack of real-time control and some 

 type of postlaunch reprogramming capability could either prevent recovery of 

 the vehicle or cause the vehicle to be misdirected or lost. 



SUPERVISORY CONTROL: FIBER-OPTIC DEVELOPMENT TESTS 



During September 1979, another series of tests was performed with the 

 vehicle to determine if the supervisory-control hardware and software archi- 

 tecture were functioning as designed and to study the dynamics of the fiber- 

 optic link deployment. Again, the tests were performed in the TRANSDEC pool 

 to aid visual and photographic observation and to protect against loss of the 

 vehicle. Topside console programs used approximately 12 kilobytes of memory, 

 and the major portions of the programs were updated to PLM. A television 

 camera and light were mounted on the vehicle, but were not electrically con- 

 nected or used. The fl uxgate-updated gyro compass was used for this series of 

 tests, replacing a magnetometer compass used during the initial tests. Most 

 of the remaining electronic hardware stayed the same. A coffee can, nylon 

 funnel, and 1/2-in PVC pipe were used as the fiber-optic deployment canister, 

 which was temporarily strapped to the bottom of the vehicle's frame (see 

 figure 19). Although deployment tests were performed, no actual fiber-optic 

 communication link existed and there was no additional software to support 

 real-time control of the vehicle. 



Accompl ishments 



The two-processor, supervisory-controlled configuration operated without 

 difficulty. There were no more problems encountered using this more complex 

 structure than were observed during the initial tests with the single vehicle 

 processor architecture. The more versatile trajectory design program, added 

 to the console since the initial configuration, greatly enhanced the operator- 

 to-console interaction speed. 



The basic approach for deploying the optical-fiber link was validated, 

 amd photographic coverage of the vehicle as it deployed the fiber-optic cable 

 was obtained. Several runs were successfully made deploying unclad fiber, 

 fiberglass-clad fiber, and dummy fiber (nylon line). 



Problems Encountered 



BATTERY LIFE. Although the use of lead-acid batteries is not a technological 

 problem, much time was wasted because of the poor condition of some of the 

 batteries. In general, the use of the parallel-series chain of the 2-V, 

 5-A-hr cells caused much of the problem. This eventually led to the adoption 

 of a single-series chain of the more powerful 2-V, 25-A-hr cells. 



MAN/MACHINE INTERFACE. Although much of the new software added to the console 

 programs greatly enhanced the console-to-operator interaction speed, the man/ 

 machine interface problem remained an important consideration. It is very 

 difficult in a short amount of time to communicate to a vehicle a-priori the 



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