Embodiments provide a fluid detection device including a casing connectable to a tube filled with water and allows the water to flow to a hollow inner part; a partition wall deformable so that the hollow inner part is divided into a fluid chamber filled with the water and an air chamber opened to the atmosphere; a slide tip disposed inside the fluid chamber; and a tip sensor disposed outside the casing. According to at least one embodiment, a slide holding part which holds the slide tip slidably forward and backward is formed inside the fluid chamber, an opening part is formed in the air chamber, a magnet is disposed in the casing, the slide tip includes a magnet provided at a position facing the magnet and repelling the magnet.

A resonant pressure sensor includes a first substrate including a diaphragm and at least one projection disposed on the diaphragm, and at least one resonator disposed in the first substrate, at least a part of the resonator being included in the projection, and the resonator being disposed between a top of the projection and an intermediate level of the first substrate.

Provided is a pressure detection device including: a pressure detection unit; a flow passage unit; and a mounting unit configured to removably mount the flow passage unit on the pressure detection unit. The pressure detection unit has a pressure detecting diaphragm and a sensor rod arranged at the center part of a first surface of the pressure detecting diaphragm, protruding toward the flow passage unit along a first axis orthogonal to the pressure detecting diaphragm, and having a top surface orthogonal to the first axis. The flow passage unit has a flow passage diaphragm, and a displacement of the flow passage diaphragm in contact with the top surface is transmitted to the pressure detecting diaphragm via the sensor rod in a state where the flow passage unit is mounted on the pressure detection unit by the mounting unit.

A system for non-intrusively measuring process fluid pressure within a process fluid conduit is provided. The system includes a measurement bracket configured to couple to an external surface of the process fluid conduit. The measurement bracket generates a variable gap based on deformation of the process fluid conduit in response to process fluid pressure therein. A gap measurement system is coupled to the measurement bracket and provides an electrical signal based on a measurement of the variable gap. A controller is coupled to the gap measurement system and is configured to calculate and provide a process fluid pressure output based on the electrical signal and information relative to the process fluid conduit.

A pipeline for conveying concrete determines a pressure in and/or a wall thickness of the pipeline, wherein a first length portion of the pipeline has a first wall thickness and a second length portion of the pipeline has a second wall thickness greater than the first wall thickness. The determination is made using a first strain gauge on an outer side of the first length portion and a second strain gauge on an outer side of the second length portion, wherein the strain gauges are each fixedly applied to the outer side of the length portions. By comparison of the measurements at the two strain gauges, it is possible to determine a wall thickness by determining a strain of the pipeline owing to a decrease in the wall thickness.

A pipeline for conveying concrete determines a pressure in and/or a wall thickness of the pipeline, wherein a first length portion of the pipeline has a first wall thickness and a second length portion of the pipeline has a second wall thickness greater than the first wall thickness. The determination is made using a first strain gauge on an outer side of the first length portion and a second strain gauge on an outer side of the second length portion, wherein the strain gauges are each fixedly applied to the outer side of the length portions. By comparison of the measurements at the two strain gauges, it is possible to determine a wall thickness by determining a strain of the pipeline owing to a decrease in the wall thickness.

Provided is a pressure detection device that can suppress variation in the pressure detection characteristics of a pressure detection unit from occurring due to individual differences in the shape of flow passage units, variation in work in mounting the flow passage unit on the pressure detection unit, or the like. The pressure detection device including: a pressure detection unit; a flow passage unit; and a mounting unit configured to removably mount the flow passage unit on the pressure detection unit. The pressure detection unit has a pressure detecting diaphragm and a sensor rod arranged at the center part of a first surface of the pressure detecting diaphragm. The flow passage unit has a flow passage diaphragm, and a displacement of the flow passage diaphragm in contact with the top surface is transmitted to the pressure detecting diaphragm via the sensor rod.

A resonant pressure sensor includes a first substrate and a resonator. The first substrate includes a diaphragm and a projection disposed on the diaphragm. The resonator is disposed in the first substrate, a part of the resonator being included in the projection, and the resonator being disposed between a top of the projection and an intermediate level of the first substrate. The first substrate is an SOI substrate in which a silicon dioxide layer is inserted between a silicon substrate and a superficial silicon layer. The intermediate level of the first substrate is disposed in the silicon substrate, and the resonator is disposed in the projection included in the superficial silicon layer.

Methods, systems, and devices for calibrating a barometer of a client device. A server computer accesses historical data including location data, and atmospheric pressure data collected from a plurality of client devices over a period of time. An equation system defined by the historical data is solved. The equation system has a plurality of unknown parameters, the plurality of unknown parameters comprising a barometer bias of a first client device among the plurality of client devices. The first client device is calibrated using the barometer bias.

A resonant pressure sensor includes a first substrate and a resonator. The first substrate includes a diaphragm and a projection disposed on the diaphragm. The resonator is disposed in the first substrate, a part of the resonator being included in the projection, and the resonator being disposed between a top of the projection and an intermediate level of the first substrate. The first substrate is an SOI substrate in which a silicon dioxide layer is inserted between a silicon substrate and a superficial silicon layer. The intermediate level of the first substrate is disposed in the silicon substrate, and the resonator is disposed in the projection included in the superficial silicon layer.