Abstract: A differential pressure sensor includes a body having a first end, a second end, and a wall. The first end and second end include isolator diaphragms connected to external first and second process fluid inlets. A MEMS pressure sensor including a pressure sensing diaphragm inside the cylinder has first and second sides coupled to the first and second isolator diaphragms by first and second fill fluid volumes. Sensor elements on the diaphragm are configured to provide, via associated sensor circuitry, an indication of deflection due to pressure differences between the first and second fill volumes. Electrical and fill fluid connections to the differential pressure sensor are made through radial connections in the wall of the body.

Abstract: A method for forming a pressure sensor includes forming a base of a sapphire material, the base including a cavity formed therein; forming a sapphire membrane on top of the base and over the cavity; forming a lower electrode on top of the membrane; forming a piezoelectric material layer on an upper surface of the lower electrode, the piezoelectric material layer being formed of aluminum nitride (AIN); and forming at least one upper electrode on an upper surface of the piezoelectric material layer.

Abstract: A differential pressure sensor includes a body having a first end, a second end, and a wall. The first end and second end include isolator diaphragms connected to external first and second process fluid inlets. A MEMS pressure sensor including a pressure sensing diaphragm inside the cylinder has first and second sides coupled to the first and second isolator diaphragms by first and second fill fluid volumes. Sensor elements on the diaphragm are configured to provide, via associated sensor circuitry, an indication of deflection due to pressure differences between the first and second fill volumes. Electrical and fill fluid connections to the differential pressure sensor are made through radial connections in the wall of the body.

Abstract: A method for forming a pressure sensor includes forming a base of a sapphire material, the base including a cavity formed therein; forming a sapphire membrane on top of the base and over the cavity; forming a lower electrode on top of the membrane; forming a piezoelectric material layer on an upper surface of the lower electrode, the piezoelectric material layer being formed of aluminum nitride (AIN); and forming at least one upper electrode on an upper surface of the piezoelectric material layer.

Abstract: A pressure sensor assembly includes a pressure sensor having a pressure sensing transducer connected to a plurality of electrode pins via a plurality of electrode pads disposed on the transducer, an inner casing configured to hold the pressure sensing transducer including a plurality of inner casing electrode pin channels having the electrode pins disposed therein. The pressure sensor further includes an outer casing holding the inner casing therein having a capsule header with a plurality of capsule header electrode pin channels defined therein which can include a ceramic seal disposed therein such that the capsule header electrode pin channels engage the electrode pins in an insulating sealed relationship. The outer casing further includes an isolator plate including an isolator plate fluid port defined therein and a pressure isolator disposed on the isolator plate and configured to deflect in response to a change in ambient pressure.

Abstract: A pressure sensor assembly includes a pressure sensor having a pressure sensing transducer connected to a plurality of electrode pins via a plurality of electrode pads disposed on the transducer, an inner casing configured to hold the pressure sensing transducer including a plurality of inner casing electrode pin channels having the electrode pins disposed therein. The pressure sensor further includes an outer casing holding the inner casing therein having a capsule header with a plurality of capsule header electrode pin channels defined therein which can include a ceramic seal disposed therein such that the capsule header electrode pin channels engage the electrode pins in an insulating sealed relationship. The outer casing further includes an isolator plate including an isolator plate fluid port defined therein and a pressure isolator disposed on the isolator plate and configured to deflect in response to a change in ambient pressure.

Abstract: A sensor for monitoring loads in a landing gear torque linkage includes a main pin having an axial interior bore defined therein. The main pin is configured and adapted to engage a torque link to a strut lug of a landing gear strut. A core pin is mounted axially within an interior bore of the main pin and is spaced radially inwardly from the interior bore for relative displacement with respect to the main pin. A capacitor is included having an inner capacitor plate mounted to the core pin. An outer capacitor plate is mounted to the main pin. Relative displacement of the core pin and the main pin due to loads acting on the torque link and strut lug results in relative displacement of the inner and outer capacitor plates. Signals can thereby be produced indicative of the loads acting on the torque link.

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 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. The first section includes a core and the second section includes a ring that receives the core.

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: The present invention relates to compounds being esters of 5-aminolevulinic acids or pharmaceutically acceptable salts thereof, including compounds of formula (I) R22N—CH2COCH2—CH2CO—OR1 (wherein R1 may represent alkyl optionally substituted by hydroxy, alkoxy, acyloxy, alkoxycarbonyloxy, amino, aryl, oxo or fluoro groups and optionally interrupted by oxygen, nitrogen, sulphur or phosphorus atoms; and R2 represents a hydrogen atom or a group R1, and both R2 groups may be the identical or different), and their use in diagnosis and photochemotherapy of disorders or abnormalities of external or internal surfaces of the body, and products and kits for performing the invention.

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 sensor for monitoring loads in a landing gear torque linkage includes a main pin having an axial interior bore defined therein. The main pin is configured and adapted to engage a torque link to a strut lug of a landing gear strut. A core pin is mounted axially within an interior bore of the main pin and is spaced radially inwardly from the interior bore for relative displacement with respect to the main pin. A capacitor is included having an inner capacitor plate mounted to the core pin. An outer capacitor plate is mounted to the main pin. Relative displacement of the core pin and the main pin due to loads acting on the torque link and strut lug results in relative displacement of the inner and outer capacitor plates. Signals can thereby be produced indicative of the loads acting on the torque link.

Abstract: A sensor for monitoring external loads acting on a pin assembly includes a pin having an axial interior bore defined therein and having a length defined from a first end to an opposed second end thereof. A core pin is mounted axially within the interior bore of the pin spaced radially inwardly from the interior bore for relative displacement with respect to the pin. A capacitor is provided having an inner capacitor plate mounted to the core pin, and an outer capacitor plate mounted to the pin, such that relative displacement of the core and the pin due to external loading on the pin results in relative displacement of the inner and outer capacitor plates. The capacitor is configured and adapted to be connected to an electrical circuit to produce signals indicative of external loading on the pin based on relative displacement of the inner and outer capacitor plates.

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 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. The first section includes a core and the second section includes a ring that receives the core.

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 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.