Abstract: The present invention relates to a micromachined hemispherical resonance gyroscope, which includes a resonant layer, wherein the resonant layer comprises a hemispherical shell whose top point of the hemispherical shell is its anchor point; several silicon hemispherical electrodes are arranged around the hemispherical shell, the silicon hemispherical electrodes include driving electrodes, equilibrium electrodes, shielded electrodes and signal detection electrodes or quadrature correction electrodes, the hemispherical shell and the several silicon spherical electrodes which surround the hemispherical shell constitute several capacitors.

Abstract: The present invention relates to a micromachined hemispherical resonance gyroscope, which includes a resonant layer, wherein the resonant layer comprises a hemispherical shell whose top point of the hemispherical shell is its anchor point; several silicon hemispherical electrodes are ananged around the hemispherical shell, the silicon hemispherical electrodes include driving electrodes, equilibrium electrodes, shielded electrodes and signal detection electrodes or quadrature correction electrodes, the hemispherical shell and the several silicon spherical electrodes which sunound the hemispherical shell constitute several capacitors.

Abstract: The present invention relates to a micromachined hemispherical resonance gyroscope, which comprises a resonant layer, said resonant layer comprising a hemispherical shell which has a concave inner surface and an outer surface opposite to the inner surface, and top point of the hemispherical shell being its anchor point; several silicon hemispherical electrodes being arranged around said hemispherical shell, the silicon hemispherical electrodes including driving electrodes, equilibrium electrodes, signal detection electrodes and shielded electrodes, the shielded electrodes separating the driving electrodes and the equilibrium electrodes from the signal detection electrodes, the hemispherical shell and the several silicon spherical electrodes which surround the hemispherical shell constituting several capacitors; the resonant layer being made of polysilicon or silica or silicon oxide or diamond.

Abstract: 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—formed from a single piece of material—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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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—formed from a single piece of material—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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.