An improved subsequent burial instrumented mine

Abstract

Detection of buried mines using conventional sonars is difficult, especially in complex coastal environments, which complicates naval tactical decisions such as whether to hunt, sweep, or avoid a mined area. The US Navy is therefore supporting research to develop and validate stochastic, time-dependent, mine burial prediction models. This research requires continuous monitoring of both mine behavior during burial and the near-field processes responsible for burial. Modes of burial are generally separated into two broad categories: impact burial and subsequent burial (scour and fill, creep, liquefaction, and bedform modification). Omni Technologies, Inc. (OTI) and the Naval Research Laboratory (NRL) have developed instrumented mines that measure both subsequent mine burial behavior and the processes that initiate and effect burial. In this paper we describe new instrumented mines, including acoustic sensors used to measure burial and sensors used to measure mine orientation, azimuth and movement. Sensors and methods used to measure characteristics of surface gravity waves, direction and magnitude of bottom currents, turbulent flow near the mine, initiation of bedload motion, and sediment size and concentration in the water column are also described.