A device for use in pressure sensing has a housing enclosing a chamber and having at least one port that communicates with the chamber. A pressure sensor receives fluid pressure from the chamber. The chamber has a compliance that exhibits a marked change in volumetric stiffness repeatably at a fixed pressure.

A device for use in pressure sensing has a housing enclosing a chamber and having at least one port that communicates with the chamber. A pressure sensor receives fluid pressure from the chamber. The chamber has a compliance that exhibits a marked change in volumetric stiffness repeatably at a fixed pressure.

A device for use in pressure sensing such as hydrocephalus shunts, having a housing enclosing a chamber with at least one port communicating with the chamber. A wall of the chamber includes a flexible portion or thin diaphragm that deflects with transitions in pressure to contact an upstand structure of the housing. A pressure sensor is contained within an enclosure sealed from the chamber by a flexible membrane and which receives fluid pressure from the chamber. This arrangement allows for calibration of the device by identifying a knee feature in pressure data associated with the diaphragm making contact with the upstand.

A device for use in pressure sensing such as hydrocephalus shunts, having a housing enclosing a chamber with at least one port communicating with the chamber. A wall of the chamber includes a flexible portion or thin diaphragm that deflects with transitions in pressure to contact an upstand structure of the housing. A pressure sensor is contained within an enclosure sealed from the chamber by a flexible membrane and which receives fluid pressure from the chamber. This arrangement allows for calibration of the device by identifying a knee feature in pressure data associated with the diaphragm making contact with the upstand.

In an embodiment a sensor arrangement includes a pressure sensor realized as a capacitive pressure sensor, a capacitance-to-digital converter coupled to the pressure sensor and implemented as a delta-sigma analog-to-digital converter and a reference voltage generator having a control input configured to receive a control signal and an output configured to provide a reference voltage, wherein the output of the reference voltage generator is connected to an input of the capacitance-to-digital converter, wherein the reference voltage generator is configured to set a value of the reference voltage as a function of the control signal, and wherein at least two different values of the reference voltage have the same sign and different amounts.

An atmospheric pressure adjustment apparatus is disclosed. The atmospheric pressure adjustment apparatus comprises: a speaker; a microphone; an earplug of which a main body is made of an elastic material so as to seal the external auditory meatus when the earplug is worn on the ear of a user, and which comprises an atmospheric pressure adjustment part penetrating the main body; and atmospheric pressure adjustment device for adjusting the fluid volume of the atmospheric pressure adjustment part; and a processor for outputting a sound through the speaker when the earplug is worn, measuring the air pressure difference between the middle ear internal atmospheric pressure and the external auditory meatus atmospheric pressure of the user on the basis of the strength of a received echo when the echo of the sound reflected from the eardrum of the user is received through the microphone, and adjusting the atmospheric pressure difference by moving the atmospheric pressure adjustment device according to the measured atmospheric pressure difference.

A method for monitoring a pressure sensor in a direct injection system including at least one common rail, a high-pressure fuel pump, a hydraulic circuit connecting the high-pressure pump to the common rail, a passive pressure-limiting valve connected to the hydraulic circuit, configured to open once the pressure in the hydraulic circuit is greater than a threshold pressure, so as to discharge the fuel, including the steps of detecting the opening of the pressure-limiting valve, measuring the pressure P.sub.MES corresponding to the time of opening of the pressure-limiting valve and comparing the measured pressure P.sub.MES to the threshold pressure P.sub.1 in order to detect a drift in the pressure sensor.

An apparatus for event detection is provided. The apparatus comprises an error signal determiner for determining an error signal portion depending on a pressure signal. The error signal determiner determines a predicted signal portion depending on a first signal portion of the pressure signal. The error signal determiner also determines the error signal portion depending on the predicted signal portion and depending on a second signal portion of the pressure signal, wherein the second signal portion of the pressure signal succeeds the first signal portion of the pressure signal in time. The apparatus also comprises a classifier for determining, depending on the error signal portion, whether an event of a group of one or more events has occurred or whether no event of the group has occurred.

A device and method for calibrating a first pressure sensor. The method includes: a) recursive analysis and forecasting of at least one correction function for finding a correction signal for the correction of a drift signal with the aid of a corresponding pressure reference signal, which is measured by the first pressure reference sensor, at constant internal pressure and at constant internal tube temperature; b) first calibration of a force signal, measured by the first pressure sensor and corrected using the correction signal, with the pressure reference signal, which is measured by the first pressure reference sensor, prior to an active use of the tube; and c) second calibration of the force signal, measured by the first pressure sensor and corrected using the correction signal, with the pressure reference signal, which is measured by a second pressure reference sensor during an active use of the tube.

Drive shaft monitoring system has a first and second coded disc. The first and second coded disc are provided with multiple slots or recesses evenly distributed in circumferential direction thereof. The drive shaft monitoring system includes at least two independent light sensor assemblies arranged in connection with the slots or recesses of the first and second coded disc.