A system for collecting atmospheric data includes a frame and sensors to include a sonic anemometer for measuring wind data samples in each of three dimensions, and motion sensors for measuring angles of roll motion, pitch motion and yaw motion of the sonic anemometer. A tether is coupled to a cable payout/retriever, a lighter-than-air balloon, and the frame such that the payout/retriever and balloon control movement of the frame through a region of an atmosphere. A processor receives the wind data samples and the sensed angles, and maps the wind data samples to a fixed local horizontal reference plane of the sonic anemometer that is normal to a local gravitational vector at the region of the atmosphere to generate samples of compensated data. The processor averages samples of compensated data to generate averaged compensated data that is indicative of wind speed and wind direction in the region of the atmosphere.

A rain gauge for measurement of rain fall. The rain gauge includes: a measurement chamber having an inlet port at one end and a drainage port at the other end, the drainage port being closed by a valve and programmable to be opened at predefined events to release water collected in measurement chamber; a funnel or collector adapted to receive rain fall opens into the inlet port; and an ultrasonic transducer for transmitting and receiving acoustic signals into measurement chamber. The ultrasonic transducer is programmable to determine the water level in measurement chamber. An automatic weather station including the rain gauge is also provided.

A transducer system. The system comprises a transducer and circuitry for applying an excitation waveform to excite the transducer during an excitation period. The circuitry for applying has: (i) circuitry for applying a first waveform at a first frequency; and (ii) circuitry for applying a second waveform at a second frequency differing from the first frequency.

An electronic device for measuring a speed of flow of a fluid that includes at least two electroacoustic transducers adapted for emitting and/or receiving acoustic signals through the flow of the fluid, the electronic device being adapted for determining a measurement of the speed of flow of the fluid from the characteristics of an acoustic signal emitted and one or more acoustic signals received, these received acoustic signals corresponding to reflections of the emitted acoustic signal.

An air data sensor can include an acoustic transmitter configured to output an acoustic signal into an airflow and a plurality of acoustic transducers configured to receive the acoustic signal output by the acoustic transducer. The air data sensor can also include a light source configured to output a light beam into the airflow, and a light receiver configured to receive scattered light from the light beam. The light source and the light receiver can be bistatic such that a measurement zone is formed away from the air data sensor.

A method and system may be used to measure the fluid flow rate of fluid in a pipeline. In the method and system, a signal may be transmitted by a transducer into the pipeline. The signal may be reflected by the contents of the pipeline and received by a receive transducer. Operations may be performed on the received signal to determine the fluid flow rate.

An acoustic air data system includes first and second acoustic transmitters, an array of acoustic receivers, and control circuitry. The array is positioned to receive first and second acoustic signals. The control circuitry determines time difference of arrival (TDOA) of the first and second acoustic signals. The control circuitry determines, for each of a first and second set of acoustic receiver pairs, a signal velocity of the first and second acoustic signals, respectively, based on a distance between an inner acoustic receiver and an outer acoustic receiver and a corresponding TDOA for each pair of acoustic receivers. The control circuitry estimates one or more of wind angle, speed of sound, Mach number, and true airspeed of the airflow about the exterior of the vehicle based on parameters of a best fit circle.

An apparatus for measuring a parameter of a fluid flow passing within a pipe is provided. The apparatus includes a sensing device and a processing unit. The sensing device has a sensor array that includes at least one first macro fiber composite (MFC) strain sensor disposed at a first axial position, and at least one second MFC strain sensor disposed at a second axial position. The first axial position and the second axial position are spaced apart from one another. The at least one first MFC strain sensor and the at least one second MFC strain sensor are both configured to produce signals representative of pressure variations of the fluid flow passing within the pipe. The processing unit is configured to receive the signals from the sensor array and measure one or more fluid flow parameters based on the signals.

A method of measuring the speed of a fluid comprising the following steps: generating a plurality of pseudorandom frequencies (fus_n); for each pseudorandom frequency (fus_n), emitting ultrasound signals into the fluid to travel along a path of defined length; receiving the ultrasound signals; for each received ultrasound signal, producing a travel time measurement, so as to generate for each pseudorandom frequency (fus_n) a predefined number of travel time measurements; for each pseudorandom frequency (fus_n), evaluating the accuracy of the measurements; for evaluating the speed of the fluid, making use of the measurements produced for the pseudorandom frequency that presents the greatest accuracy.

A system and method of non-intrusive anemometry. The system comprises an acoustic transmitter disposed at a boundary of fluid flow and first and second acoustic receivers adapted to receive transmissions from the acoustic transmitter. A processor is coupled to the acoustic receivers to determine the time of arrival of the transmission at the acoustic receivers. The acoustic transmitter and acoustic receivers are arranged such that the acoustic transmitter is upstream from the first acoustic receiver which is in turn upstream from the second acoustic transmitter.