Abstract: A method of and system for monitoring the acoustic transmission conditions in underwater areas using an unmanned, mobile, submersible vehicle of the type including a source of acoustic signals. The submersible vehicle is controlled so that the vehicle traverses a desired path through the water of an area of interest. As the submersible vehicle traverses the desired path, a time-synchronized acoustic signal is transmitted from the acoustic source to at least one receiver spaced from the submersible vehicle so as to generate data representing the acoustic properties of the environment in the water between the acoustic source and the at least one receiver as the submersible vehicle traverses the desired path.

Abstract: Invention relates to a novel method of and system for ranging between an acoustic source carried on an unmanned or autonomous undersea mobile vehicle (UUV or AUV) and preferably a plurality of hydrophone receivers remotely deployed from the vehicle in predetermined patterns, generally suspended from sonobuoys equipped with above-the-sea relay radio transmitting antennas, and with time synchronization provided amongst the source and the receivers, wherein the time delay from the transmissions of the source is measured by utilizing special signal processing, enabling range to be measured in close to real time by determining the product of the sound velocity and the measured time delay, and with the process continually and periodically being repeated throughout the duration of the vehicle run.

Abstract: A device that characterizes the trajectory followed by a movable object after a piece of sporting equipment comes into contact with the movable object, e.g., by identifying velocity, the distance that the object would travel if unobstructed in standard ideal conditions, the curvature of the path travelled by the object, the direction of travel of the object, or the direction or magnitude of spin of the object. The device includes at least one force sensor element arranged to be located on the piece of sporting equipment, which is held or worn by a user. The sensor element detects at least a component of the force of contact between the piece of sporting equipment and the movable object. The sensor element provides a signal representing the intensity of the component of the force of contact when the contact occurs. An electrical processing circuit is arranged to receive the signal from the sensor element and to process the signal to produce an output characterizing the trajectory of the movable object.