Abstract: Time of flight between two or more ultrasonic transceivers is measured using known delays. First and second transceivers are duty cycled, each having a respective receive period that is less than a measurement period during which the transceivers are configured to receive transmissions. An ultrasonic trigger pulse is transmitted by the first transceiver. The second transceiver, upon receiving the trigger pulse, transmits an ultrasonic response pulse after a first predefined delay time that is known to the first transceiver and greater than the receive period of the second transceiver. Subsequently, the first transceiver receives the ultrasonic response pulse and determines a receive time. The first transceiver determines the distance between the first transceiver and the second transceiver from a speed of sound, an elapsed time between the time of transmission of the trigger pulse and the receive time, and the first predetermine delay time.

Abstract: An ultrasonic sensing system includes an ultrasonic receiver configured to receive an ultrasonic signal and a gain-adjustable amplifier operably coupled to the ultrasonic receiver. The gain-adjustable amplifier is configured to amplify the ultrasonic signal according to a variable gain determined based at least in part on a value of a timer that corresponds to a measuring distance.

Abstract: Mechanical vibration may be sensed by a remotely located ultrasonic sensor. An ultrasonic wave may be transmitted from a transmitter to a vibrating surface, in which the transmitter is separated from the vibrating surface by a distance. A reflected portion of the ultrasonic wave that is reflected from the vibrating surface may be received by a receiver that is also separated from the vibrating surface by a distance. A measure of phase shift amplitude in the reflected portion of the ultrasonic wave may be determined and converted into an amplitude of a vibration of the vibrating surface.

Abstract: The present disclosure provides systems and methods for manufacturing food products. In a general embodiment, systems for manufacturing a food product include at least one heat exchanger, at least one food product tank, at least one conduit downstream of the food product tank for flow of the food product, and a flow detection device coupled to an exterior of the conduit. The flow detection device includes a processor and a computer readable medium storing instructions which, when executed, cause the processor to perform a spread spectrum analysis of the flow of the food product through the conduit. Methods for manufacturing food products are also provided.

Abstract: A lithographic apparatus includes a support constructed to support a patterning device, the patterning device being capable of imparting a radiation beam with a pattern in its cross-section to form a patterned radiation beam; a substrate table constructed to hold a substrate; a projection system configured to project the patterned radiation beam onto a target portion of the substrate; a sensor array positioned and arranged to detect an acoustic wave from a movable part of the lithographic apparatus, a controller, the controller having a controller input connected to the sensor array so as to receive a sensor array output signal, and a controller output connected to at least one actuator arranged to act on the movable part, the controller being arranged to: calculate a movement of the movable part from the sensor array output signal, and drive via the controller output the at least one actuator in response to the calculated movement.

Abstract: An apparatus for providing buoyancy to a towed marine divertor and for reducing drag acting on the divertor as the equipment is towed through water. A float attached to the divertor has a curved leading end oriented toward the tow direction to reduce water drag acting against the float. The float can be integrated within the divertor or can be attached with wire rope or chains to lower the divertor within the water. The trailing end of the float can be tapered, and vane foils can be attached to the float outboard side.

Abstract: A depth sounder repeater providing a remote display of the depth of a body of water digitally or by meter movement, a depth alarm, a lost echo signal, and a meter scale expansion for shallow depth display in conjunction with a ship's sonar, display of "alarm depth" while setting. The depth display may be digital or analog and multiple displays are possible as required. The depth sounder repeater includes a signal processor for providing signals initiated with the main ultrasonic pulse transmission from the ship's sonar and terminated with the receipt of the first echo of the corresponding main transmitted pulses. The signal processor signals may then be used to initiate and terminate production of a train of clock pulse signals which are counted to provide a digital depth display, or alternatively the signal processor signal may be integrated in analog meter display apparatus.

Abstract: An air gun firing sensor apparatus and system are provided for determining the instant of firing of an air gun by sensing pressure changes within the air gun when it is being fired. A pressure-change-sensitive transducer assembly is inserted into a socket in the housing of a solenoid-controlled valve of an air gun with a passage from the air gun communicating with the transducer for transmitting to the transducer a pressure surge occurring within the air gun whenever it is fired. The transducer assembly has a cylindrical casing with a head mounted at one end. The head includes a plurality of spaced recesses which are adapted to communicate with the passage leading from the air gun.

Abstract: A gauge for measuring variations in distance of a surface relative to a reference by means of phase shifts in a zone of high acoustic impedance. A gauge head is provided with a first orifice for emitting acoustic waves, driven by a reference signal, toward a surface positioned very close to the gauge head, forming a high impedance zone. A second orifice in the gauge head picks up acoustic waves subjected to the zone and these waves are converted to electrical signals for comparison to the reference signal in a phase detector. The phase error between the two signals is indicative of surface distance variations.

Abstract: An ulrasonic liquid level measurement device is used to measure the depth of a flowing liquid in a channel using an ultrasonic transducer that is positioned out of contact with the liquid and above and directed toward the channel. An ultrasonic burst is directed toward the channel and the reflected echo from the surface of the liquid is returned and sensed by the transducer. The transit time of ultrasonic transmission and echo return is indicative of the liquid level. An adjustable discriminator is provided to specify a maximum liquid level in the channel and a minimum liquid level, which, typically is the floor of the channel. The maximum and minimum levels are adjustable to accomodate variable channel configurations and transducer mounting arrangements. Automatic adjustment is provided to compensate for different cable lengths which may be used to connect the ultrasonic transducer to the transducer driver and receiving section.

Abstract: An echo sounder has a transducer for transmitting and receiving pulses of energy, a rotary arm display and a meter or digital display. The rotary arm is arranged to cause the transducer to transmit a pulse of energy on each occasion it passes a datum position. The motor of the rotary arm display may be switched off while simultaneously energizing an oscillator having an output frequency equal to that of the rotational speed of the motor prior to deenergization.