4D VELOCITY SENSOR DEVELOPMENT

THE PURPOSE OF PHASE I OF THIS PROPOSED PROJECT IS TO CONDUCT RESEARCH TO ESTABLISH THE FEASIBILITY OF DEVELOPING A 4D VELOCITY SENSOR FOR SUBSURFACE AND SURFACE VESSEL NAVIGATIONAL USE IN A WIDE RANGE OF OCEANOGRAPHIC APPLICATIONS. THE SENSOR WILL EMPLOY ACOUSTIC CORRELATION VELOCITY LOG (CVL) TECHNOLOGY TO DETERMINE THE TRUE "EARTH FRAME" VERTICAL AND HORIZONTAL COMPONENTS OF SENSOR VELOCITY AS A FUNCTION OF TIME BY CORRELATING THE ECHOES RETURNED FROM THE SEABED. THE NOVEL APPROACH PROPOSED IS THE USE OF A DUAL FREQUENCY CVL TO ACHIEVE HIGH ACCURACY OVER A WIDE RANGE OF OPERATIONAL ALTITUDES (10 TO 20,000 FEET). THE ALGORITHM APPROACH AND THEORETICAL EQUATIONS FOR DETERMINING THREE-AXIS VELOCITY, AS WELL AS A STUDY OF THE RANDOM AND BIAS ERRORS ASSOCIATED WITH THE CVL WILL BE INVESTIGATED. A CONTROLLED TEST USING RD INSTRUMENT'S EXISTING OPERATIONAL 75 KHZ CORRELATION SONAR WILL BE CONDUCTED TO VALIDATE THE THEORETICAL PREDICTIONS.