Abstract: A system and method for incorporating presence-sensing technology into furniture is provided. More particularly, the invention relates to incorporating a conductive medium into the periphery of a furniture item, such as an adjustable bed, for detecting the presence of a user or other body. The bed includes a mattress with a covering material and a tape edge surrounding the perimeter of the mattress. A capacitive wire is coupled the tape edge, and is adapted to have a voltage based on proximity of an object to the capacitive wire. The bed also includes a processor coupled to the capacitive wire. The processor receives information provided by the capacitive wire, determines when a change in voltage satisfies a threshold, and indicates whether presence is detected. Based on a determination of presence, or lack of presence, a variety of corresponding features of the adjustable bed may be activated.

Abstract: A capacitance measurement circuit for determining a sense current of a capacitive sensor which includes at least one electrically conductive sense electrode and at least one electrically conductive guard electrode. The measurement circuit includes at least one switch member that is remotely controllable by a switch remote control unit, wherein the at least one switch member in at least one closed state is configured to provide an additional electrical path between the at least one guard electrode and a reference potential.

Abstract: An immersion detector having a thermoresistive detector with at least two temperature probes. The immersion device has a capacitive detector having a capacitor, a cap surrounding said temperature probes and the capacitor, said cap having orifices putting said temperature probes and the capacitor into fluid flow communication with an external medium (EXT) surrounding said immersion detector.

Abstract: A gas sensing device that includes differential temperature compensation.

Abstract: A proximity switch assembly and method for detecting activation of a proximity switch assembly is provided. The assembly includes a plurality of proximity switches each having a proximity sensor providing a sense activation field and control circuitry processing the activation field of each proximity switch to sense activation. The control circuitry monitors the signal responsive to the activation field and determines a differential change in generated signal, and further generates an activation output when the differential signal exceeds a threshold. The control circuitry further distinguishes an activation from an exploration of the plurality of switches and may determine activation upon detection of a stable signal.

Abstract: A method for compensating for a dielectric absorption effect in a measurement configuration during measurements by an instrument having measurement terminals includes providing a feedback loop in the instrument, the loop having a gain adjustment and a simulation impedance and being adapted to provide a signal counter to the dielectric absorption at the measurement terminals; applying a transient calibration signal to the test terminals for at least two values of the gain adjustment; measuring a response to the calibration signal for each of the at least two values; and determining an operating value of the gain adjustment based on the measured responses. The operating value is used for subsequent measurements by the instrument, the simulation impedance modeling the dielectric absorption characteristics of the measurement configuration.

Abstract: The invention relates to devices for liquid level detection (LLD). It relates to a laboratory device having an electronic circuit for detecting a liquid level in a liquid container, a feeler, which can be advanced, and which is connected to an input side of the electronic circuit, and having a movement device, which allows the feeler to be advanced in the direction of the liquid in the liquid container. Upon the immersion of the feeler in the liquid, a capacitance change is caused in the electronic circuit, which triggers a signal in the circuit. The laboratory device comprises a reference circuit, which is connected to the input side of the circuit, and which specifies an effective capacitance on the input side of the circuit. A sequence controller is used, which causes the triggering of a test by the application of a control signal to the reference circuit, the control signal causing an increase of the effective capacitance through a switching procedure.

Abstract: An apparatus including a sensor array, configured to produce an array output value in response to an environmental stimulus, and a controller, the sensor array including a plurality of sensors and a common output terminal connected to the respective outputs of the sensors, each sensor having first and second electrodes configured to output a respective sensor output value in a particular environment based on the areas of the first and second electrodes and/or the spacing therebetween, the controller configured to control which of the sensors are connected to the common output terminal using respective switches to vary the effective area and/or spacing of the sensor array such that the array output value at the common output terminal, based on the contribution of the respective sensor output values of the connected sensors, is held at a reference value.

Abstract: A 3D Motional Command System (MCS) is disclosed for interactive gaming, computer interfaces, communications, imaging, and geological exploration. The system can perform standoff gesture recognition and also function as touch-screens. E-field sensors and array topologies are disclosed comprised of FET discrete transistors. The designs facilitate the fabrication of high density sensor arrays similar to LCD displays. The system can be used in portable and wearable electronic devices. Uses are for PC computers, portable devices, and gaming systems such as the Wii. Other applications include wireless connection of sensor and audio data from a simple headphone jack output.

Abstract: A gas sensing device that includes differential temperature compensation.

Abstract: Systems provide for a test system for capacitors in a digitally controllable oscillator (DCO). The system includes: capacitor toggling logic configured to switch on and off a selected one of the capacitors at a modulation frequency; a tone generator configured to generate a tone; a mixer configured to receive the tone and an output carrier signal from the DCO while the capacitor toggling logic is switching the selected one of the capacitors on and off and to output an intermediate frequency signal having FM sidebands based on the modulation frequency and relative capacitor size; and an evaluation circuit configured to evaluate a frequency deviation associated with the selected one of the capacitors based on at least one of the FM sidebands.

Abstract: A humidity sensor includes a detection device with a capacitance changing with humidity at a first ratio and a reference device with a capacitance changing with humidity at a second ratio smaller than the first ratio. The detection device has detection electrodes facing each other with a first gap and a detection humidity-sensitive film covering the detection electrodes. The reference device has reference electrodes facing each other with a second gap and a reference humidity-sensitive film covering the reference electrodes. The detection humidity-sensitive film and the reference humidity-sensitive film are made from the same material and have the same thickness. The detection electrodes and the reference electrodes are made from the same material and have the same width and thickness. The second ratio peaks when the second gap is equal to a predetermined value. The second gap is smaller than the first gap and the predetermined value.

Abstract: In method and a control device for triggering person protection device, a signal of a planarly measuring environment sensor system and a second signal of a contact sensor system are evaluated separately in order to produce a respective trigger signal. These two trigger signals are then gated in order to produce a third trigger signal. A trigger circuit triggers the person protection device as a function of this third trigger signal.

Abstract: The electronic circuit has a capacitive sensor that includes two capacitors mounted in differential, whose common electrode can move relative to each fixed electrode of the two capacitors to alter the capacitive value of each capacitor. The electronic circuit has an interface connected to the capacitive sensor, which includes a charge transfer amplifier unit connected to the common electrode, an integrator unit, and an excitation unit arranged between the output of the first integrator unit and the sensor to polarise each fixed electrode of the sensor capacitors at a determined voltage value. A compensation capacitor is connected to the input of the integrator unit. The electronic circuit interface includes comparison means for comparing the output voltage with a comparison voltage to control disconnection of the compensation capacitor at the integrator unit input, if the deviation between the output voltage and the comparison voltage exceeds a determined voltage threshold.

Abstract: A wood monitoring system and method is disclosed for monitoring lumber characteristics (e.g., lumber moisture) in environments of extremely high and prolonged temperature and moisture, e.g., a kiln. The monitoring system and method includes: (a) Sensors (provided within lumber stacks), wherein such sensors are battery powered and wirelessly communicate measurements indicative of moisture content of the wood adjacent to and/or between metal plates provided in an electrical circuit with the sensors and the wood between the plates; (b) Computer implemented methods and systems for wireless communication that conserve sensor battery power such that the sensors can operate for, e.g., six months within extremely adverse temperature and moisture environmental variations; and (c) Computer implemented methods and systems for estimating moisture content with a wood/lumber stack, and for predicting such moisture content (e.g., as a substantially steady state within the wood) after drying completion.

Abstract: In a capacitance detecting device including an offset adjustment circuit for removing offset from charge transmitted to an integrator from a charge reading mechanism, the offset adjustment circuit includes a variable capacitance element switching the number of capacitative elements connected in parallel to a charge transmission line made up of a plurality of the capacitative elements and setting the number to a predetermined capacitance value; and a capacitative element for adjustment connected in parallel to the variable capacitance element and parallel, and having a capacitance value corresponding to the minimum value of the capacitative elements constituting the variable capacitance element. Driving is controlled so that offset removal is performed only N times (M>N; M and N are natural numbers) in the capacitative element for adjustment while offset removal is repeated M times in the variable capacitance element.

Abstract: An object of the invention is to provide a fuel-aspect sensor having higher detection accuracy. A first electrode is inserted into a hole formed in a first housing member. A cylindrical second electrode is inserted into and firmly fixed to the first electrode by a cylindrical insulating member. A first elastic member, for example, made of rubber, is arranged between the first electrode and a second housing member. The first electrode has a large-diameter portion, which is biased by the first elastic member toward a sealing surface formed on an inner wall of the hole, so as to fluid-tightly seal a space between the first electrode and the second housing member.

Abstract: The invention proposes a circuit arrangement for determination of a measuring capacitance (1), comprising a reference circuit portion for defined periodic charging and discharging of a predefined reference capacitance (1a), and a measuring circuit portion for defined periodic charging and discharging of the measuring capacitance (1) to be determined, and at least one circuit portion (4, 7; 4a, 7a) intended to determine at least one value (M2) characteristic of the charging time curve of the reference capacitance (1a) and for deriving at least one value (M1) characteristic of the charging time curve of the measuring capacitance (1), as well as a circuit portion (9) for comparing the at least one value (M2) characteristic of the charging time curve of the reference capacitance (1a) with the at least one value (M1) characteristic of the charging time curve of the measuring capacitance (1), and for deriving from that comparison the value of the measuring capacitance (1).

Abstract: An occupant detection system and method are provided. The system includes a capacitive sensor having an electrode arranged in a seat proximate to an expected location of an occupant for sensing an occupant presence approximate thereto. The capacitive sensor is configured to provide an output indicative of the sensed occupant presence. Occupant detection circuitry is included for processing the capacitive sensor output and determining a wet seat condition and generating a wet seat fault based on a determined wet seat condition. The occupant detection circuitry further detects a state of occupancy of the seat based on the capacitive sensor output and the wet seat fault.

Abstract: A moisture metering calibration method and system for, e.g., determining the moisture lumber within a lumber drying kiln is disclosed. Calibration of moisture indicative electrical signals obtained from, e.g., moisture sensing capacitive plates spaced apart within a stack of drying lumber is performed, wherein long lengths (e.g., up to 1000 linear feet or more) of coaxial cable can be used for transmitting the signals, and effectively removing signal anomalies induced in such cabling so that accurate lumber moisture measurements result. Such extended cable lengths provides flexibility with respect to placement of electronic moisture metering equipment. This flexibility allows such equipment to be placed in an environmentally-controlled enclosure, rather than on the weather exposed exterior of a kiln whose lumber is being monitored.

Abstract: The invention concerns a measuring apparatus for the detection of foreign bodies in a product, in particular in tobacco, cotton or some other fibrous product, having a measuring device, a device for generating an alternating electromagnetic field in the measuring device, which is influenced by a product which is arranged in a measuring volume of the measuring apparatus, a circuit device which includes the measuring device and which is designed to determine at least one suitable measurable variable of the alternating field influenced by the product, and an evaluating device which is designed for detection of the foreign body by suitable evaluation of the measurable variable determined with the circuit device, and is distinguished in that the measuring device is a measuring capacitor and the frequency of the alternating field is in the high-frequency range below the microwave range. The application further concerns a corresponding measuring method.

Abstract: An apparatus for cooking foods comprises a cooking chamber provided with humidity-detecting device arranged in such a way as to detect the humidity in said cooking chamber, wherein said humidity-detecting device comprises a capacitive sensor; a system for controlling the humidity in a chamber for cooking foods comprises a humidity detecting device provided with a capacitive sensor.

Abstract: A system and/or method for sensing the presence of moisture (e.g., rain) and/or other material(s) on a window such as a vehicle window (e.g., vehicle windshield or backlite). In certain example embodiments, a capacitor-based system and/or method is provided for auto-correlating sensor data to determine the existence of a material on the window, and then cross-correlating sensor data to identify the type and/or amount of that material (e.g., rain). This data may be used to actuate and/or deactivate a vehicle's wiper(s), and/or adjust wiper speed. In certain example embodiments, the sensor may include an array of at least two capacitors. In certain example embodiments, the system and/or method may perform check(s) to enhance the accuracy of the detection by comparing, for example, the sign of autocorrelation values, maximum autocorrelation values, and/or gradients of autocorrelation values.

Abstract: On-chip real-time moisture detection circuitry for monitoring ingress of moisture into an integrated circuit chip during the operational lifetime of the chip. The moisture detection circuitry includes one or more moisture-sensing units and a common moisture monitor for monitoring the state of each moisture-sensing units. The moisture monitor can be configured to provided a real-time moisture-detected signal for signaling that moisture ingress into the integrated circuit chip has occurred.

Abstract: A process is disclosed for evaluating a measuring device comprising a capacitor (CM), with stages for charging the capacitor (CM) over an initial charging period (tk1, tk2) and for determining the capacitance charge as an initial measured value (tml). To determine a measuring condition that changes a normal state of the capacitance, e.g., moist as opposed to dry surroundings for the measuring cell, the process exhibits the following additional steps: charging the capacitance (CM) over a second charging period (tk2), which differs from the first charging period (tk1); determining the charge of the capacitance (CM) as a second measured value (tm2); and comparing the first and second measured values (tk1, tk2) to establish the comparative result.

Abstract: A method and apparatus for monitoring and determining the moisture content of a sample substance inside a closed container. The apparatus includes a parallel capacitance circuit formed by a source of AC voltage supplied to a reference container and a sample container. The method does not require penetration or opening of the sealed sample container nor the destruction of the sample, and can be used to rapidly determine moisture content under normal storage conditions or at elevated or lower temperatures that may be used in a drying process.

Abstract: An electrostatic type voltmeter for measuring the potential on a surface, the voltmeter including a probe; a support for supporting the probe in spaced relationship with the surface, the probe having a plurality of spacing element sites thereon for measuring a distance between each of the plurality of spacing element sites and a corresponding area on the surface opposite of each of the plurality of spacing element sites; a plurality of electrostatic element sites, intermixed and adjacent to the plurality of spacing element sites on the probe, for measuring a voltage between each of the plurality of spacing element sites and an area on the surface adjacent to the corresponding area opposite of each of the plurality of spacing element sites. A processor for compensating an output signal of the probe in response to the measurements received from the plurality of spacing element sites and the plurality of electrostatic element sites.

Abstract: A portable grain moisture measurement device has an automatic grain moisture measurement actuation system whenever the compaction of the grain within a test cell of the device is at a preset value and upon such automatic actuation a visual display is activated to indicate that a moisture measurement is being taken as well as the sounding of an audible alarm indicating this measurement to warn the user that further compaction of the grain is unnecessary.

Abstract: A differential capacitance probe device for process control involving aqueous dielectric fluids is disclosed. The device contains a pair of matched capacitor probes configured in parallel, one immersed in a sealed container of reference fluid, and the other immersed in the process fluid. The sealed container holding the reference fluid is also immersed in the process fluid, hence both probes are operated at the same temperature. Signal conditioning measures the difference in capacitance between the reference probe and the process probe. The resulting signal is a control error signal that can be used to control the process.

Abstract: An electrical system for measuring humidity which is capable of measurements accurate to +/−6 percent from board to board. The accuracy provided by this electrical system makes it possible to correlate errors in data on backup magnetic tapes to variations in humidity. The electrical system consists of an oscillator whose frequency is dependent on the capacitance of a capacitor used in the circuit. The capacitance value of the capacitor is dependent on the relative humidity. The frequency of the oscillator is translated to a humidity value by an electronic counter and a microprocessor.

Abstract: A paving material analyzer system is disclosed that uses paving material impedance to determine paving material density. The invention also includes a method for analyzing paving material, in particular, determining paving material density. The paving material density can also be used to determine a percentage of maximum compaction. A paving material analyzer is also disclosed that determines paving material density regardless of moisture presence on the paving material.

Abstract: Impedance between potential sensing electrodes of a high impedance meter is measured by applying a ramp waveform through a capacitor coupled to one of the electrodes to generate a substantially constant current, a measure of impedance being obtained by comparing this to the potential developed across the electrodes when a different current is flowing.

Abstract: A capacitive sensor for detecting raindrops on the external surface of a vehicular windshield, relying for its operation on the compensation of the capacitive signals which are due to variation of the dielectric constant of the windshield's glass with temperature, and on the elimination of capacitive signals which result from electrostatic interference or moisture deposition occurring at the inner surface of the windshield. The sensor includes electrodes printed on the internal surface of the windshield and is shielded by a grounded conducting enclosure. Another embodiment of the invention simultaneously senses raindrops on the external side of the window and moister on the internal surface of the windshield.

Abstract: A capacitive sensor is employed to measure the dielectric constant of miscible liquids, and thereby determine the relative concentration of the two liquids. Further, a feedback circuit may be provided to change the operation of the system in accordance with the relative concentration of the liquids. Further, circuit arrangements may be provided to adjust the sensitivity and offset of the electrical circuit included in the system to match the output of the sensor with the dielectric constants being measured.

Abstract: The invention relates to a method and a device for determining proportions of solid matter in a test material. In order to reliably and easily determine proportions of solid matter in a test material, even in the case of transparent matter or matter of a similar color to the test material, the test material is exposed to an electric field and dielectric properties of the field are determined with the test material present. Two electrical quantities are determined from the dielectric properties and combined, resulting in a characteristic value which is independent of the mass of the test material. The characteristic value is compared with a previously determined characteristic value for the matter in question and the proportion of solid matter is determined therefrom.

Abstract: The method and structure of a moisture measuring device that creates an electric field and then determines a moisture content of a specimen based on the effect the moisture of the specimen has on the electric field.

Abstract: A capacitive sensor for measuring a characteristic of a fluid or a filling depth of a liquid in a container is constructed of a printed circuit board that is either flexible or has stiff and flexible sections along its length. Metal coatings forming capacitor plates are formed, for example by printed circuit techniques on one or both sides of the circuit board which is then bent into such a configuration that two capacitor plates forming a capacitor face each other across a spacing that is accurately maintained by spacers. The bent shape of the circuit board has, for example, a U-configuration, an inverted S-configuration, or an e-configuration. Additional metal coatings are provided for screening purposes against adverse field influences. Conductor leads are provided on the printed circuit board for connecting the capacitor plates to an evaluating circuit, and the metal screens to a reference potential such as ground.

Abstract: Provided is a concentrated replenisher automatic diluting apparatus and method that can easily and accurately dilute concentrated replenishers and that can set the amount of agents included in the replenishers supplied to processing tanks to ideal values in a system where a variety of concentrated replenishers are supplied from a processing agent kit at the same time and the concentrated replenishers are diluted. When a liquid level detector of one of replenisher tanks detects that a replenisher held in the replenisher tank has reached a lower limit level, predetermined amounts of different kinds of concentrated replenishers are supplied to the replenisher tanks from a replenishing agent kit. Water is supplied to the replenisher tanks through a wash pump and a wash valve in order to dilute the concentrated replenishers.

Abstract: A digital liquid level sensing apparatus for detecting variations in the dielectric of a substance being sensed. The apparatus includes a capacitive element array including a plurality of individual (i.e., segmented) input plates positioned along an axis of measurement of a fluid to be detected. The array also includes a common output plate having a length sufficient to span the entire accumulated length of the input plates. A controller sequentially applies DC excitation pulses to the input plates which cause a series of output currents to be coupled onto the output plate. The output currents are input to a current-to-voltage amplifier which generates a series of corresponding analog output voltages. The analog output voltages are then input to a peak voltage detector circuit to generate a series of peak voltage signals representative of the magnitudes of the analog output voltages.

Abstract: System and method for producing paper that employ an apparatus for measuring electrical characteristics of a fibrous composition. The apparatus comprises a plurality of conductivity (or resistance) detectors each comprising a sensor that is sensitive to the conductivity (or resistance) and the proximity of the material (e.g., fibrous composition) to the sensor. Measurements from the apparatus relate to the zeta potential of the fibrous materials in the composition. The zeta potential profiles corresponding optimized configurations of the sheetmaking process can be employed to monitor and control the process.

Abstract: An ice detector includes a pair of electrodes connected by a pair of leads to a control unit which measures the total impedance between leads to thereby sense and detect the presence of ice and other contaminants formed on top thereof utilizing a comparator circuit. The electrodes are integrated into patch which can be placed at different locations on an aircraft.

Abstract: A method and apparatus for determining specific material characteristics of plastic materials in which the plastic material is disposed between electrodes of a capacitive sensor and the impedance is measured and compared to a reference value, preferably stored in a computer.

Abstract: A system and method of producing a paper product from a wetstock solution using a sensor for sensing resistive impedance changes of the wetstock on the support web of the system. The resistive impedance changes are used to measure physical characteristics such as water weight of the wetstock on the support web of a sheetmaking system. The system includes a fixed impedance element coupled in series with a sensor portion between an input signal and ground. The sensor portion is an electrode configuration which includes at least two electrodes with a portion of the wetstock residing between and in close proximity to the electrodes. The sensor exhibits a variable impedance resulting from changes in the physical characteristics of the wetstock.

Abstract: A sensor system is operable for detecting the presence of water in an oil emulsion inside the lower gear unit of a marine engine, and for providing an alarm signal when the presence of water is detected within the gear unit. The sensor system includes a ring oscillator circuit and a symmetrical array of passive input probes which are disposed in the oil/water emulsion inside the oil chamber. Each of the passive input probes is electrically connected to the ring oscillator circuit wherein the probes function as fixed capacitors for measuring the electrical characteristics of the emulsion. When a voltage is applied to the oscillator circuit, the oscillator circuit generates an oscillating signal that circulates at a frequency which varies according to the dielectric-properties of the liquid emulsion. When water is introduced into the chamber, the water is emulsified with the oil thereby changing the electrical characteristics of the oil.

Abstract: In a circuit arrangement for determining differences in capacitance, two capacitors (1,2) are alternately connected to an integrator with differential amplifier (3) whose input current is positive (+I) when the first capacitor (1) is integrated or negative (-I) when the second capacitor (2) is integrated, whereby the switches (5,6,7) are synchronously switched. The differential amplifier keeps the voltages at the two capacitors the same. A clocked control device (4) controls the synchronous switching and separately measures and adds the respective charging and discharging times and, as warranted, measures and adds the output voltage of the integrator and controls the last charging cycle such that the voltage at the capacitors is subsequently equal to the initial voltage. The relative or absolute differences in capacitance are calculated from the identified sums and can be digitally output.

Abstract: An impedance measurement system including a series circuit having a reference impedance leg and a measurement leg, the measurement leg including first and second spaced apart electrodes defining a region for receiving a sample of material to be tested; an oscillator circuit connected in parallel with the series circuit and providing a reference voltage and a signal voltage proportioned to the impedance of the measurement leg; and a detector circuit producing an output voltage proportional to changes between the reference voltage and the signal voltage.

Abstract: Digital tilt level sensing probe system comprising a set of multiple capacitor elements in a fluid container arranged along an axis of measurement where each multiple capacitor element represents a discrete level increment in dielectric material fluid to be measured. Individual capacitors in each element are horizontally spaced to reflect a level differential upon tilting of the fluid container from its normal attitude. In the case of a probe for sensing tilting in a single plane, a one-piece body is employed to include integral capacitor elements, mounting pad, connector, custom IC pad, and circuitry molded into such body. Alternative references may be employed for comparison with each capacitor assigned a unique time slot in a switching sequence.

Abstract: Digital level sensing probe system including digital probe constructed of two (2) concentric cylinders, forming a set of discrete, cylindrical capacitors that use the substance whose level is to be measured as a dielectric material. The set of capacitors is arranged along the axis of measurement where each capacitor represents a discrete level increment. Each capacitor is assigned a unique time slot in a switching sequence. The first level capacitor is used as a reference to which all other capacitors are sequentially compared. In the switching sequence, an AC signal is applied across each capacitor and compared with the inverted signal which is applied across the first level capacitor. A logic "1" results when the substance is present and a logic "0" when the substance is absent. The logic is decoded and converted to display the appropriate quantity of substance measured.

Abstract: Digital level sensing probe system including digital probe constructed of two (2) concentric cylinders, forming a set of discrete, cylindrical capacitors that use the substance whose level is to be measured as a dielectric material. The set of capacitors is arranged along the axis of measurement where each capacitor represents a discrete level increment. Each capacitor is assigned a unique time slot in a switching sequence. The first level capacitor is used as a reference to which all other capacitors are sequentially compared. In the switching sequence, an AC signal is applied across each capacitor and compared with the inverted signal which is applied across the first level capacitor. A logic "1" results when the substance is present and a logic "0" when the substance is absent. The logic is decoded and converted to display the appropriate quantity of substance measured.