Abstract: Airspeed direct sensing transducer apparatus in a system where fast response gust sensors are aircraft wing mounted, each gust sensor mounted on opposite wing halves feeding the absolute value of low-pass filtered direct sensed airstream gust cross-component signals to a difference amplifier providing an electrical indication when one side of the aircraft “sees” disturbed or turbulent air as may be encountered when an aircraft trailing wake-vortex or similar hazardous atmospheric disturbance is approached. This enables the pilot to take evasive action to mitigate or avoid the turbulence disturbance, enhancing free flight aircraft operation.

Abstract: Airspeed direct sensing transducer apparatus in a system where fast response gust sensors are aircraft wing mounted, each gust sensor mounted on opposite wing halves feeding the absolute value of low-pass filtered direct sensed airstream gust cross-component signals to a difference amplifier providing an electrical indication when one side of the aircraft “sees” disturbed or turbulent air as may be encountered when an aircraft trailing wake-vortex or similar hazardous atmospheric disturbance is approached. This enables the pilot to take evasive action to mitigate or avoid the turbulence disturbance, enhancing free flight aircraft operation.

Abstract: The airspeed transducer includes a pair of electrically heated cylindrical sensing elements in a parallel arrangement that is exposed broadside to the incident airstream, simultaneously measuring both instantaneous airspeed and a cross-component of airspeed. The tangent cylindrical elements are joined together with a filler in order to present a flat front face to the airstream, and they are oriented so that the plane defined by their parallel axes is perpendicular to airstream flow. The transducer is electrical with no moving parts and electronic circuitry provides for transducer excitation, operation, and signal readout. A single transducer can be used for measurement of instantaneous airspeed, angle-of-attack, turbulence cross-component, and total turbulence that can also be used in the measurement and computation of T.K.E. or turbulent kinetic energy.

Abstract: A turbulence sensor whose signal output is processed to substantially reduce accumulated turbulence signal bandwidth and provide a permanent stored record in which maximum information content is preserved while a minimum of data samples are recorded. Both turbulence energy and turbulence intensity sensors are disclosed. Aircraft mounting of multiple sensors together with correlation monitoring relating to airframe structural integrity prediction is disclosed. A turbulence energy sensor for ground monitoring of conditions such as wake vortex and wind shear turbulence as well as cyclonic system detection in remote geographic areas is also disclosed. An aircraft turbulence sensor, combining a fast response thermal anemometer airspeed transducer together with a ducted thermal anemometer direction transducer sensing angle-of-attack is disclosed.

Abstract: An anemometer transducer wind set with no moving parts for determining both wind speed magnitude and wind direction components having an omnidirectional wind speed resultant thermal anemometer transducer and a directional orthogonal or right angle ducted thermal anemometer transducer. Omnidirecitonal single-ended element design configuration is disclosed that is used to control thermal anemometer resultant wind element spatial response to wind flow together with a wind set array configuration that combines the resultant wind measurement transducer with an orthogonal dual component ducted thermal anemometer wind direction sensing transducer.

Abstract: A thermal anemometer transducer wind set for determining both wind speed and wind direction having an omnidirectional wind speed resultant sensing transducer element and a component directional anemometer transducer sensing element pair that are all operated as constant temperature anemometers. Omnidirectional element configuration design is disclosed that is used to control element spatial response to wind flow and also determine sign sense of direction. Additional wind set array configurations are disclosed that combine the resultant wind measurement transducer with dual component arrays, three-phase arrays, and a three-dimensional pyramidal array.

Abstract: A constant temperature anemometer having a single self-heated non-zero temperature coefficient resistive anemometer sensing element operated as one arm of a four-arm Wheatstone bridge whose opposing or reference arm contains a temperature sensor, with the four-arm bridge operated as a single arm of a second Wheatstone bridge whose reference arm contains a second temperature sensor, the second bridge operated as the controlled bridge in a constant temperature (constant resistance) anemometer configuration resulting in feedback controlled constant resistance operation of the bridge within a bridge. The sub-bridge output is determined by a differential amplifier, thereby removing the need for a d-c offset or reference signal to remove or suppress the mean heating term obtained electrically across the single heated anemometer sensing element. In effect, differential operation is provided for a single element anemometer transducer.

Abstract: The directional thermal anemometer transducer includes an electrically non-conducting substrate having at least two areas substantially thermally isolated from one another covered with a resistive sensing conductor, the conductor extending only within the region of connected flow over the transducer. The resistive sensing conductors can be of metal film or resistive material which exhibits a change in its electrical resistance as a function of temperature. Barrier plates mounted at each end and perpendicular to the longitudinal axis of the transducer interferes with flow parallel to the transducer in order to create wake turbulence behind the plates.

Abstract: The directional thermal anemometer transducer includes an electrically non-conducting substrate having at least two areas substantially thermally isolated from one another covered with a resistive sensing conductor, the conductor extending only within the region of connected flow over the transducer. The resistive sensing conductors can be of metal film or resistive material which exhibits a change in its electrical resistance as a function of temperature. In one embodiment, the substrate consists of a pair of circular cylindrical members with a resistive sensing conductor extending from the stagnation region within the area of connected flow. In another embodiment, the substrate is a single cylindrical member with two regions having the resistive sensing conductor. In yet another embodiment of the invention, the substrate is a rectangular cylindrical member having a resistive sensing conductor on two opposing faces.

Abstract: A thermal anemometer, including a constant temperature anemometer bridge excitation circuit together with multiple signal comparators and a tapped resistance reference divider, providing a linearized digital output signal, together with a digitally controlled output section that presents a simultaneous linear analog output signal. All logic switching is actuated by the anemometer signal itself. Both unipolar (non-directional) and bipolar (directional) constant temperature anemometer signals are linearized, digitized, and processed with a minimum number of steps and component parts to provide simultaneous digital and analog output signals. Generic transducer electrical output signal digitizing is disclosed.

Abstract: The directional thermal anemometer transducer includes an electrically non-conducting substrate having at least two areas substantially thermally isolated from one another covered with a resistive sensing conductor, the conductor extending only within the region of connected flow over the transducer. The resistive sensing conductors can be of metal film or resistive material which exhibits a change in its electrical resistance as a function of temperature. In one embodiment, the substrate consists of a pair of circular cylindrical members with a resistive sensing conductor extending from the stagnation region within the area of connected flow. In another embodiment, the substrate is a single cylindrical member with two regions having the resistive sensing conductor. In yet another embodiment of the invention, the substrate is a rectangular cylindrical member having a resistive sensing conductor on two opposing faces.

Abstract: A constant temperature sorption hygrometer comprising a differential pair of substrate-supported heated metal film sensing elements, one coated with a hygroscopic layer of microporous aluminum oxide and the other coated with a non-hygroscopic protective coating or uncoated, both operated by feedback controlled constant temperature bridge circuits; together with alternate forms of hygrometer transducer apparatus employing differential sorption detection of water vapor.

Abstract: A constant temperature hygrometer comprising a piezoelectric substrate supporting a temperature coefficient resistor on one face and a conducting electrode on the opposite face, one or both conductor faces partially or completely covered by a hygroscopic layer of aluminum oxide anodized from aluminum metal deposited on one or both conductor faces, operated by a feedback controlled constant temperature bridge circuit, excited and read out by radio frequency oscillator circuitry; together with alternate forms of hygrometer transducer structures and water vapor sorptive materials.

Abstract: A directional heat loss anemometer transducer for sensing both the speed and direction of motion of a fluid, liquid or gas in which the transducer is immersed. The transducer is constructed of fine long cylindrical resistive conductors which are axially disposed about a central, cylindrical supporting body, wherein at least two conductors serve as a direction sensing pair which can also be used to determine impinging fluid speed. The sensing conductor pair are joined together by an adhesive connecting means thereby preventing independent flow between the individual conductors of the conductor pair. The electrical conductors can be metallic or resistive films which are deposited on a cylindrical supporting body, or they may be individual wires of circular cross section. Each conductor is made of a material which exhibits a change in its electrical resistance as a function of temperature.

Abstract: A directional heat loss anemometer transducer for sensing both the speed and direction of motion of a fluid, liquid or gas in which the transducer is immersed. The transducer is constructed of fine long cylindrical resistive conductors which are axially disposed about a supporting body wherein at least two conductors serve as a direction sensing pair which can also be used to determine impinging fluid speed. For flow in opposite directions across the transducer a third conductor can be used to independently sense speed when it is mounted so as to function as a freely supported fine cylinder. The direction sensing conductors are joined to the supporting body by an adhesive connecting means thereby preventing independent flow between the individual conductors of the conductor pair. The electrical conductors can be metallic or resistive films which are deposited on a cylindrical supporting body, or they may be individual wires of circular cross-section.

Abstract: A directional hot film anemometer transducer for sensing the speed and direction of a fluid velocity vector that describes the motion of the fluid in which the transducer is immersed. The transducer is constructed of two cylindrical resistive electrical conductors which are mounted on either side of a third cylindrical member that is used for mechanical support and which also may be used as a biasing heated resistive electrical conductor so as to improve the spatial directional response of the three element transducer. The three cylindrical elements are supported so as to maintain their axes within a single plane and are joined by bridging means which provides a degree of thermal isolation between the conductors in order to facilitate the determination of instantaneous fluid flow direction.

Abstract: A fluid flow sensor apparatus for determining speed, mass flow and direction of motion relative to a fluid in which the sensor is immersed. The sensor is constructed of at least two spaced apart resistive electrical conductors which are mechanically supported to provide a degree of thermo isolation between the conductors in order to effect the determination of instantaneous fluid flow direction. A pair of the conductors is joined so that the flow around separate conductors is avoided so as to force one conductor to be a leading edge to the flow stream and the other conductor to be a trailing edge, with separate flow passing over the conductor pair. The electrical conductors can be wires or they can be metallic or resistive films which are deposited on a supporting body. The conductor is made of a material which exhibits a change in the electrical resistivity as a function of temperature.