Remote Sonar Sensing of At-Sea Oil Layer Thicknesses

A research and development effort was undertaken to define and implement appropriate sonar hardware and signal processing techniques in order to measure oil layer thicknesses in the dynamic environment of an oil spill. The resultant Sonar Oil Thickness Sensor (SOTS) is an integrated inverted echo sounder and microprocessor. Control and processing facilities of the microprocessor are used to compensate for the response of the acoustic signal to waves, nonhomogeneous oil layers, emulsification, and complete data dropouts. This paper presents a statement of purpose, design goals, theory and implementation of the sensing instrument, and characteristics of the system performance. Reference is also made to the various applications of this instrument, such as oil tanker cargo monitoring, hazardous chemical monitoring, and nonintrusive capillary wave measurement.