Rosemount Aerospace Limited

Goodrich Corporation

United Technologies Corporation

Rohr, Inc.

Sensors Unlimited

Shuwen Guo

Odd Harald Steen Eriksen

Kimiko Childress

Odd Harald Eriksen

Thomas G Wiegele

Lawrence Joseph Stang

David Patrick Potasek

Chuang-Chia Lin

Christopher Apanius

Kenneth G Goldman

Alexander Spivak

Anita Fink

Yosief Abraha

Loren E St Clair

Timothy R O'Meara

James J Pohl

Ross Hoffman

Kimiko J Childress

Odd Haral Steen Eriksen

A system for determining in-plane acceleration of an object. The system includes an in-plane accelerometer with a substrate rigidly attached to an object, and a proof mass&#x2014;formed from a single piece of material&#x2014;movably positioned a predetermined distance above the substrate. The proof mass includes a plurality of electrode protrusions extending downward from the proof mass to form a gap of varying height between the proof mass and the substrate. The proof mass is configured to move in a direction parallel to the upper surfaces of each of the plurality of substrate electrodes when the object is accelerating, which results in a change in the area of the gap, and a change in capacitance between the substrate and the proof mass. The in-plane accelerometer can be fabricated using the same techniques used to fabricate an out-of-plane accelerometer and is suitable for high-shock applications.

In-plane capacitive mems accelerometer

A capacitive strain sensor for sensing strain of a structure. The sensor includes a first section attached to the structure at a first location and a second section attached to the structure at a second location. The first section includes a capacitor plate electrically isolated from the structure and the second section includes two electrically isolated capacitive plates, both of the plates being electrically isolated from the structure. A flexible connector connects the first section to the second section. The capacitor plate of the first section is separated from the two capacitive plates of the second section by at least one capacitive gap. When strain is experienced by the structure, a change occurs in the capacitive gap due to relative motion between the first and second sections.

Sensor for measuring large mechanical strains with fine adjustment device

A method for forming a transducer including the step of providing a semiconductor-on-insulator wafer including first and second semiconductor layers separated by an electrically insulating layer, wherein the first layer is formed or provided by hydrogen ion delamination of a starting wafer. The method further includes doping the first layer to form a piezoresistive film and etching the piezoresistive film to form at least one piezoresistor. The method also includes depositing or growing a metallization layer on the semiconductor-on-insulator wafer, the metallization layer including an electrical connection portion that is located on or is electrically coupled to the piezoresistor. The method includes removing at least part of the second semiconductor layer to form a diaphragm, with the at least part of the piezoresistor being located on the diaphragm, and joining the wafer to a package by melting a high temperature braze material or a glass frit material.

Method for forming a transducer

A strain sensor device for measuring loads on aircraft landing gear. This is done by measuring strains in the lower end of the strut, by which we infer the loading in the entire landing gear structure. These strains can be very large (as high as 10,000 microstrain) and can be imposed in numerous random directions and levels. The present invention includes a removable sensor assembly. An electromechanical means is presented that can accommodate large strains, be firmly attached to the strut, and provide good accuracy and resolution.

Systems and methods for mounting landing gear strain sensors

A system for monitoring landing gear position. An example rotation position sensor includes a hub mount that locks within a shaft of a joint, a first sensor attached to the hub mount, and a second sensor attached to the rotatably attached part that does not rotate. The hub mount includes a nut that has a partially tapered surface and a threaded cavity. The nut is secured within the shaft. The hub mount also includes a mounting unit that has a partially tapered surface that is in opposition to the partially tapered surface of the nut. A fastener secures the hub mount to the nut. In one example, the first sensor includes a magnetometer and the second sensor includes magnet(s). In another example, the first sensor includes inductor sensor(s) and the second sensor includes device(s) that causes a change in an inductance value of the inductor sensor(s) as the joint rotates.

Systems and methods for measuring angular motion

Disclosed are capacitive pressure probes or sensors for high temperature applications. The capacitive pressure sensors of the present invention include, inter alia, a sapphire diaphragm which is disposed within an interior sensing chamber of the probe housing and has a first electrode formed on a central portion thereof. The central portion of the diaphragm and the first electrode are adapted and configured to deflect in response to pressure variations encountered within an interior sensing chamber and by the pressure sensor. A sapphire substrate which has a second electrode formed thereon is fused to the sapphire diaphragm about its periphery to form a sapphire stack and to define a reference chamber therebetween. Prior to fusing the sapphire diaphragm to the sapphire substrate, all contact surfaces are chemically treated and prepared using plasma activation, so as to create a bonding layer and to reduce the temperature required for the fusion.

High temperature capacitive static/dynamic pressure sensors and methods of making the same

A pendulous capacitive accelerometer including a substrate having a substantially planar upper surface with an electrode section, and a sensing plate having a central anchor portion supported on the upper surface of the substrate to define a hinge axis. The sensing plate includes a solid proof mass on a first side of the central anchor portion and a substantially hollow proof mass on a second side of the central anchor portion, providing for reduced overall chip size and balanced gas damping. The solid proof mass has a first lower surface with a first electrode element thereon, and the substantially hollow proof mass has a second lower surface with a second electrode element thereon. Both the solid proof mass and the hollow proof mass have the same capacitive sensing area. The sensing plate rotates about the hinge axis relative to the upper surface of the substrate in response to an acceleration.

Pendulous accelerometer with balanced gas damping

A transducer for use in a harsh environment including a substrate and a transducer die directly coupled to the substrate by a bond frame positioned between the substrate and the transducer die. The transducer die includes a transducer element which provides an output signal related to a physical characteristic to be measured, or which receives an input signal and responsively provides a physical output. The transducer further includes a connecting component electrically coupled to the transducer element at a connection location that is fluidly isolated from the transducer element or the surrounding environment by the bond frame. The bond frame is made of materials and the connecting component is electrically coupled to the transducer element by the same materials of the bond frame, and the connecting component is electrically isolated from the bond frame.

Transducer with fluidly isolated connection

A harsh environment transducer including a substrate having a first surface and a second surface, wherein the second surface is in communication with the environment. The transducer includes a device layer sensor means located on the substrate for measuring a parameter associated with the environment. The sensor means including a single crystal semiconductor material having a thickness of less than about 0.5 microns. The transducer further includes an output contact located on the substrate and in electrical communication with the sensor means. The transducer includes a package having an internal package space and a port for communication with the environment. The package receives the substrate in the internal package space such that the first surface of the substrate is substantially isolated from the environment and the second surface of the substrate is substantially exposed to the environment through the port. The transducer further includes a connecting component coupled to the package and a wire electrically connecting the connecting component and the output contact such that an output of the sensor means can be communicated. An external surface of the wire is substantially platinum, and an external surface of at least one of the output contact and the connecting component is substantially platinum.

High temperature resistant solid state pressure sensor

Disclosed is a capacitive pressure probe for high temperature applications, such as for use in a gas turbine engine. The capacitive probe or pressure sensor of the present invention includes, inter alia, a sensor housing that defines an interior sensing chamber having a pressure port and an interior reference chamber positioned adjacent to a sensing electrode. The reference chamber is separated from the sensing chamber by a deflectable diaphragm made from Haynes 230 alloy, wherein the deflection of the diaphragm in response to an applied pressure in the sensing chamber corresponds to a change in capacitance value detected by the sensing electrode.

High temperature capacitive static/dynamic pressure sensors

A process for fabricating a pendulous accelerometer, including the steps of: providing a first substrate having a top planar surface, etching a portion of the first substrate to a first predetermined depth from the top planar surface to form a plurality of first protrusions, providing a second substrate, etching a portion of the second substrate to a second predetermined depth to form a plurality of second protrusions, bonding planar surfaces of the first protrusions to planar surfaces of the second protrusions, and etching a portion of the first substrate from an opposite side of the first substrate to a third predetermined depth equal to or greater than the difference between the total thickness of the first substrate and the first predetermined depth to form a freely rotatable sensing plate that includes a substantially hollow proof mass.

Wafer process flow for a high performance MEMS accelerometer

A method for forming a transducer including the step of providing a semiconductor-on-insulator wafer including first and second semiconductor layers separated by an electrically insulating layer. The method further includes depositing or growing a piezoelectric film or piezoresistive film on the wafer, depositing or growing an electrically conductive material on the piezoelectric or piezoresistive film to form at least one electrode, and depositing or growing a bonding layer including an electrical connection portion that is located on or is electrically coupled to the electrode. The method further includes the step of providing a ceramic substrate having a bonding layer located thereon, the bonding layer including an electrical connection portion and being patterned in a manner to generally match the bonding layer of the semiconductor-on-insulator wafer. The method also includes causing the bonding layer of the semiconductor-on-insulator wafer and the bonding layer of the substrate to bond together to thereby mechanically and electrically couple the semiconductor-on-insulator wafer and the substrate to form the transducer, wherein the electrical connection portions of the bonding layers of the semiconductor-on-insulator wafer and the substrate are fluidly isolated from the surrounding environment by the bonding layers.

Method for making a transducer

A method for bonding two components together including the steps of providing a first component, providing a second component, and locating a first eutectic bonding material between the first and second component. The first eutectic bonding material includes at least one of germanium, tin, or silicon. The method further includes the step of locating a second eutectic bonding material between the first and second component and adjacent to the first eutectic bonding material. The second eutectic bonding material includes gold. The method further includes the step of heating the first and second eutectic bonding materials to a temperature above a eutectic temperature of an alloy of the first and second eutectic bonding materials to allow a hypoeutectic alloy to form out of the first and second eutectic bonding materials. The method includes the further step of cooling the hypoeutectic alloy to form a solid solution alloy bonding the first and second components together.

Transient liquid phase eutectic bonding

A pressure sensor for use in a harsh environment including a substrate and a sensor die directly coupled to the substrate by a bond frame positioned between the substrate and the sensor die. The sensor die includes a generally flexible diaphragm configured to flex when exposed to a sufficient differential pressure thereacross. The sensor further includes a piezoelectric or piezoresistive sensing element at least partially located on the diaphragm such that the sensing element provides an electrical signal upon flexure of the diaphragm. The sensor also includes an connecting component electrically coupled to the sensing element at a connection location that is fluidly isolated from the diaphragm by the bond frame. The bond frame is made of materials and the connecting component is electrically coupled to the sensing element by the same materials of the bond frame.

Transducer for use in harsh environments

A method for making a pressure sensor including the steps of providing a substrate and forming or locating a pressure sensing component on the substrate. The method further includes the step of, after the forming or locating step, etching a cavity in the substrate below the pressure sensing component to define a diaphragm above the cavity with the pressure sensing component located on the diaphragm. The pressure sensing component includes an electrically conductive electron gas which changes its electrical resistance thereacross upon movement of the diaphragm.

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Lakeville, MN, United States of America

Shuwen Guo