The invention relates to a marker device and a tracking system for tracking the marker device, wherein the marker device comprises a rotationally oscillatable magnetic object and wherein the rotational oscillation is excitable by an external magnetic field, i.e. a magnetic field which is generated by a magnetic field providing unit 20, 31 that is located outside of the marker device. The rotational oscillation of the magnetic object induces a current in coils, wherein based on these induced currents the position and optionally also the orientation of the marker device is determined. This wireless kind of tracking can be carried out with relatively small marker devices, which can be placed, for instance, in a guidewire, the marker devices can be read out over a relatively large distance and it is possible to use a single marker device for six degrees of freedom localization.

The invention relates to a measurement device 1 comprising a rotatable magnetic object 4 which can oscillate with a resonant frequency if excited by an external magnetic torque. The measurement device 1 is adapted such that the resonant frequency depends on the temperature or on another physical or chemical quantity like pressure, in order to allow for a wireless temperature measurement or measurement of the other physical or chemical quantity via an external magnetic field providing the external magnetic torque. This measurement device can be relatively small, can be read-out over a relatively larger distance and allows for a very accurate measurement.

An apparatus for measuring pressure is disclosed. The apparatus can be used to measure static pressures or dynamic pressures as would a conventional microphone, but can be integrated with antenna elements, and can be implemented without need for conductive elements in the array itself to provide the sensed pressure signal for processing. Instead, diaphragm movement is remotely and wirelessly sensed and used to determine pressure.

Temperature sensors, pressure sensors, methods of making the same, and methods of detecting pressures and temperatures using the same are provided. In an embodiment, the temperature sensor includes a ceramic coil inductor having a first end plate and a second end plate, wherein the ceramic coil inductor is formed of a ceramic composite that comprises carbon nanotubes or, carbon nanofibers, or a combination of carbon nanotubes and carbon nanofibers thereof dispersed in a ceramic matrix; and a thin film polymer-derived ceramic (PDC) nanocomposite disposed between the first and the second end plates, wherein the thin film PDC nanocomposite has a dielectric constant that increases monotonically with temperature.

Temperature sensors, pressure sensors, methods of making the same, and methods of detecting pressures and temperatures using the same are provided. In an embodiment, the temperature sensor includes a ceramic coil inductor having a first end plate and a second end plate, wherein the ceramic coil inductor is formed of a ceramic composite that comprises carbon nanotubes or, carbon nanofibers, or a combination of carbon nanotubes and carbon nanofibers thereof dispersed in a ceramic matrix; and a thin film polymer-derived ceramic (PDC) nanocomposite disposed between the first and the second end plates, wherein the thin film PDC nanocomposite has a dielectric constant that increases monotonically with temperature.

Measurement of pressure of a fluid in a vessel using a cantilever spring in the vessel; a magnet connected to the cantilever spring in the vessel; an electromagnet outside of the vessel operatively connected to the magnet and the cantilever spring in the vessel, wherein the electromagnet induces movement of the magnet and the cantilever spring in the vessel, and wherein the movement is related to the pressure of the fluid in the vessel; a receiving coil operatively positioned relative to the magnet, wherein movement of the cantilever spring and the magnet in the vessel creates an electromotive response in the coil; and a controller analyzer connected to the receiving coil, wherein the controller analyzer uses the electromotive response in the coil for measuring the pressure of the fluid in the vessel.

A pressure sensor comprises a deformable substrate, at least one coil supported by the substrate and responsive to a changing coil drive signal to produce a changing magnetic field, a fluid chamber having a first wall formed by the substrate and a second wall formed by a conductive material and positioned proximate to the at least one coil so that the changing magnetic field produces eddy currents within the conductive material that generate a reflected magnetic field, and at least one magnetic field sensing element configured to detect the reflected magnetic field and produce a signal responsive to a distance between the magnetic field sensing element and the second wall. The substrate is deformable by fluid pressure within the fluid chamber and the deformation of the substrate changes the distance between the magnetic field sensing element and the second wall.

A leakage detection device for detecting water leakage in a water pipe of a water system after a stop valve of the water system is closed. The leakage detection device may be part of a stop valve, and may include an interior chamber connectable to the water pipe in such a way so as to receive a stagnation volume of the water when the water flow through the water pipe is stopped by the stop valve. An actuation element provides a force acting on a diaphragm or a piston in the direction of the first interior chamber and against or into the stagnation volume of water. If water leakage is present in the water pipe, the diaphragm or piston will move under the applied force to compensate for the leakage in the water pipe. A sensor unit may detect water leakage in the water pipe based on the movement.

A pressure sensor that includes a housing with an upper housing part and a lower housing part, the upper housing part and the lower housing part being configured such that a chamber is formed between them. A diaphragm is provided between the upper housing part and the lower housing part, and dividing the chamber into an upper chamber and a lower chamber. A magnetic core is linked to the diaphragm. An operating spring includes a top end and a bottom end, the top end being supported against the upper housing part and the bottom end being supported against the magnetic core. At least one of the top end and the bottom end of the operating spring is provided with an adhesive layer. The pressure sensor enables the operating spring and the magnetic core to move integrally with each other, thereby improving the precision of the pressure sensor.

A pressure sensor includes a conductive substrate having a cavity which forms a thin portion that can be deformed by a pressure differential. A magnetic field sensor has at least one coil responsive to a changing coil drive signal and positioned proximate to the thin portion of the substrate that induces eddy currents in the thin portion that generate a reflected magnetic field. Magnetic field sensing elements detect the reflected magnetic field and generate a magnetic field signal. The magnetic field sensor is positioned so that deformation of the thin portion of the substrate causes a distance between the thin portion of the substrate and the magnetic field sensor to change.