Accurate Sensing of Low Speed Vehicle Motion Relative to a Moving Platform

Signal Systems Corporation (SSC) will develop a Maritime Acoustic Relative VELocity (MARVEL) sensor to measure the Doppler shift of an ultrasonic signal induced by the relative motion between an unmanned aerial vehicle (UAV) and the deck. SSC will demonstrate the feasibility of using an innovative, small, lightweight, low-cost array of directional ultrasound sensors to produce real-time tracking velocity measurements (TVM) at low taxiing/creeping speeds. Ultrasound sensors operating in continuous active sonar (CAS) mode are a natural fit for measuring relative velocity. The sensor is always on, allowing for the uninterrupted tracking of the Doppler shift over time. SSCs approach uses Acoustic Doppler to sense motion more directly than imaging or range finding approaches. This sensing modality does not depend on lighting conditions and a significant range of the ultrasonic wavelengths are relatively immune to backscatter from mist and fog, making it a natural choice for day and night maritime conditions.