Abstract:
A method is provided for making multiple environmental measurements using a single sensing element. Each sensing element (sensel) includes a thin-film transistor (TFT) and a passive element. Typically, a plurality of sensels is provided arranged into an array. In response to an electrical stimulus, an electrical measurement is supplied that is responsive to a change in TFT electrical characteristic correlated to a first environmental condition, as well as a change in a characteristic of the passive element correlated to a second environmental condition. When the sensels are formed in an array, a plurality of electrical measurements is supplied corresponding plurality of locations on a monitored surface. Some exemplary environmental conditions include temperature, pressure, moisture, chemicals, oxygen, solution pH, salinity, and shear. The method determines the first environmental condition independent of the second environmental condition, while determining the second environmental condition independent of the first environmental condition.
Abstract:
The present invention relates to a printed circuit board having a substrate and a condensation sensing circuit (8) comprising an interdigital capacitor with an electrode pattern with at least a pair of electrodes of a condensation sensing element (9) in the form of microstrip lines on said substrate. Said condensation sensing circuit (8) comprises a microcontroller (1 ) that generates a square wave which is fed into a phase shifting stage (3) having said condensation sensing element (9).
Abstract:
A method and apparatus (100) for detecting moisture. An oscillatory electrical signal S 1 generated by an oscillator (3) is propagated into a body (48) that includes an electrically insulative material (25). A signal due to S 1 emerges from the body (48) as an oscillatory electrical signal S 2 . The signals S 1 and S 2 differ in phase by ΔΦ , wherein ΔΦ is indicative of moisture along a path traversed by S 1 within the insulative material (25), and wherein the conductance σ of the insulative material (25) is also indicative of the moisture along the path traversed by S 1 within the insulative material (25). S 2 is received at a sensing surface (17) of a sensing part (e.g., probe (1), sensing antenna, etc.) and then transmitted to a moisture detecting device (100). The moisture detecting device (100) determines from S 1 and S 2 a measure M of the moisture as a function of ΔΦ or as a function of σ.
Abstract:
A driving circuit for a fluid conductivity sensor includes a pulse width modulation unit, an H-bridge, first and second differential amplifiers, and an analog-to-digital converter (ADC). The pulse width modulation unit generates two opposing driving signals. The H-bridge receives the two opposing driving signals and generates two H-bridge outputs. The first differential amplifier includes first inputs connected in parallel to a shunt resistor. One of the first inputs is coupled to the two generated H-bridge outputs. The second differential amplifier includes second inputs connected in parallel with a pair of terminals having a sensor attached thereto. One of the second inputs and the pair of terminals receive a signal from the other of the two generated H-bridge outputs. The ADC receives a first output representative of a first current from the first differential amplifier; and a second output representative of a second current from the second differential amplifier.
Abstract:
Es wird ein Sensorelement für Gassensoren zur Bestimmung von Partikeln in Gasgemischen, insbesondere für Rußsensoren, mit mindestens einem dem zu bestimmenden Gas ausgesetzten Messelement (14, 16), mindestens einem in das Sensorelement integrierten Heizelement (40) und mindestens einem in das Sensorelement integrierten Temperaturmesselement (30) beschrieben. Dabei weist ein erstes Element der Elemente Messelement (14, 16), Temperaturmesselement (30) und Heizelement (40) einen ersten gemeinsamen elektrischen Kontakt (20, 46, 48) mit einem anderen Element der Elemente Messelement (14, 16), Temperaturmesselement (30) und Heizelement (40) auf und das erste Element weist einen weiteren gemeinsamen elektrischen Kontakt (20, 46, 48) mit einem weiteren Element der Elemente Messelement (14, 16), Temperaturmesselement (30) und Heizelement (40) auf.
Abstract:
A conductivity measurement system provides one or more DC pulses to first and second electrodes submerged in an aqueous solution such as, for instance, the wash water of an industrial dishwasher. The voltage at the first electrode is measured at a sequence of at least three predetermined times after initiation one of one of the DC pulse (150, 152, 154, 156). A non-linear curve fitting function is applied to the sequence of at least three voltage measurements to calculate the voltage at the first electrode at the beginning of the DC pulse(s), commonly denoted as being at time t=0 (170). The resulting calculated voltage at time t=0 is then used to calculate the conductivity of the solution, and /or to control operation of the chemical dispenser, and/or to perform another predetermined system analysis or system control function (172, 174, 176, 178). In addition, the difference between two of the measured voltages, such as the first and second measured voltages, is compared to a predetermined threshold value to determine whether the electrodes are so contaminated that polarization compensation is no longer feasible, thereby signaling that the electrodes should be cleaned or replaced (160, 162, 164).
Abstract:
Es wird ein Verfahren zur Funktionskontrolle eines Sensors (10) zur Detektion von Teilchen, insbesondere von Ruß, wobei der Sensor (10) mindestens zwei Messelektroden (20, 22) und ein Substrat (18) aufweist, auf dem die Messelektroden (20, 22) angeordnet sind, vorgeschlagen. Das Verfahren umfasst die folgenden Schritte: Durchführen einer ersten Strom-Spannungsmessung zum Ermitteln einer ersten Messgröße, Durchführen einer zweiten Strom-Spannungsmessung zum Ermitteln einer zweiten Messgröße, wobei eine Messelektrode (22) der Messelektroden (20, 22) auf ein anderes elektrisches Potential (50) gelegt wird, Durchführen einer dritten Strom-Spannungsmessung zum Ermitteln einer dritten Messgröße und Bilden eines Korrekturwerts zum Korrigieren der zweiten Messgröße mittels der ersten Messgröße und der dritten Messgröße.
Abstract:
Embodiments of the present disclosure provide techniques and configurations for an apparatus for providing liquid quality measurements. In one instance, the apparatus may comprise a printed circuit board (PCB) having first and second electrodes associated with the PCB, to directly contact with a liquid to obtain a plurality of electrical parameters of the liquid when electrical current passes between the first and second electrodes while in contact with the liquid, wherein the electrical parameters are associated with quality of the liquid. The PCB may further comprise circuitry disposed thereon and coupled to the first and second electrodes to collect the electric parameters of the liquid. Other embodiments may be described and/or claimed