ABSTRACT 



An electronic system has been developed to measure and record certain 

 hydrodynamic characteristics of a towed buoy to be the antenna platform for 

 a submarine communications system designated BIAS (Buoy Integrated 

 Antenna Submarine). The system is for use during submarine development- 

 assist tow trials. The quantities measured are buoy pitch, horizontal stabi- 

 lizer angle, depth (shallow and deep), cable tension at the submarine, cable 

 scope (fine and coarse), submarine depth, and speed. 



An automatic depth-keeping servo system also was developed for the 

 buoy in conjunction with the above measurement system to determine the 

 feasibility of this type of device in a varying seaway. 



A second electronic measurement system was developed to measure and 

 indicate the required hydrodynamic characteristics of the buoy necessary for 

 operation of the system during submarine patrols. The quantities measured 

 are displayed as meter readouts and include buoy depth (shallow and deep), 

 cable tension at the submarine, and cable scope (fine and coarse). 



ADMINISTRATIVE INFORMATION 



The work described in this report was performed for the Naval Ship Engineering Center 

 (NAVSEC) as part of Subproject S3203, David W. Taylor Naval Ship Research and Develop- 

 ment Center (DTNSRDC) Work Unit 1-1548^02. 



INTRODUCTION 



At the request of NAVSEC, DTNSRDC undertook a program to develop a towed buoy 

 and cable system to act as an antenna platform for a communications system for use on ASW 

 submarines. The system is designated BIAS (Buoy Integrated Antenna Submarine). 



As part of the BIAS buoy development program, two electronic measurement systems 

 and an automatic buoy depth control system were designed and fabricated. One measurement 

 system was designed to accurately measure buoy and towcable parameters for validation of 

 performance predictions at sea. An automatic depth control system was designed to control 

 the buoy for two ranges of depth-keeping: (1) near-surface following and (2) the sub-surface 

 depth required for very low frequency (VLF) reception. A second measurement system was 

 manufactured for permanent placement aboard the submarine to be used for operation of the 

 BIAS system while deployed at sea. 



The approach taken by the David W. Taylor Naval Ship Research and Development Center 

 was to select the necessary sensors, to design the electronic systems for data transmission and 

 recording (or indicating), to design an automatic buoy depth-keeping servo-control system, 

 and to package the resulting components for evaluation experiments in the BIAS buoy system. 



