Abstract: A capacitive sensor includes a sensing antenna electrode for capacitively coupling to a counterelectrode to form a capacitance, this capacitance being responsive to an electric-field-influencing property of an object or person proximate to the antenna electrode. The counterelectrode may be part of the capacitive sensor. The capacitive sensor also includes a capacitive sensing network connected to the antenna electrode to apply an oscillating signal thereto and to determine the capacitance based upon characteristics of the oscillating signal. The capacitive sensing network includes at least one inductor and a plurality of reactive components arranged to form a resonant network together with the capacitance, the plurality of reactive components being activatable and deactivatable in such a way as to modify a resonance frequency of the resonant network.

Abstract: A vehicle seat suspension mat (12) comprises suspension springs (14) for supporting a seat cushion (16) and a pressure sensor module (18) arranged on the springs for being applied against a bottom surface of the seat cushion. The pressure sensor module produces an electrical signal responsive to pressure acting on it. The pressure sensor module comprises a base plate (20) and a film-type pressure sensor (22) arranged on the base plate. The pressure sensor includes a pressure-sensitive cell (36). The base plate comprises a frame (26) and an actuator (28) that is linked to the frame in such a way that it is capable of movement relative to the frame. The actuator is arranged against the pressure-sensitive cell of the film-type pressure sensor and comprises a fixation element (48) fixing the base plate to the springs. The fixation element provides a spacing between the base plate and the springs.

Abstract: A method for contamination detection in a time-of-flight (TOF) range imaging system is described, wherein the TOF range imaging system receives light reflected from a scene, through an optical interface, on an imager sensor having an array of pixels, and wherein distance information and amplitude information are determined for the sensor pixels. The presence of contamination on the optical interface is determined on the basis of amplitude information determined for the sensor pixels.

Abstract: A method for matching the pixels (10-1, 10-2) of a first range image of a scene (18) as seen from a first point of sight (14) with pixels (12-1, 12-2) of a second range image of the scene as seen from a second point of sight (16) comprises the following steps: providing the first range image as a grid of source pixels (10), on which the scene is mapped in accordance with a first projection associated with the first point of sight, wherein each source pixel has a point in the scene projected thereon in accordance with the first projection and has associated therewith a range value determined for that point in the scene; providing a grid of target pixels (12) for the second range image and a second projection associated with the second point of sight; and for each one of the target pixels, a) determining which source pixel would have the same point (P1, P2) in the scene projected thereon in accordance with the first projection as the target pixel would have projected thereon in accordance with the second projec

Abstract: A combined seat heater and capacitive occupancy sensor comprises a heating element (10) connected between a first (21) and a second (22) node, and a capacitive sensing network connected to the heating element to apply an oscillating voltage thereto and to derive the capacitive load of the heating element. A common mode choke (16) connects the first and second node to a third (23) and fourth (24) node, respectively. The capacitive sensing network comprises an oscillator (28), AC-coupled to the third and/or the fourth node to drive oscillating voltage into that node, and a transimpedance amplifier (32), which has a first input to receive the oscillating voltage as reference voltage and a second input operatively connected to the heating element. The transimpedance amplifier maintains a voltage on its second input equal to the reference voltage by driving a current into the second input. An output signal (44) indicates the AC component of the current driven into the second input.

Abstract: A capacitive sensing system for being connected to a heating element comprises a capacitive detector connectable to the heating element and a common mode choke for essentially preventing alternating current from flowing from the heating element to the heating current supply. The capacitive detector is configured for driving an alternating current into the heating element and for producing an output indicative of capacitance based upon the alternating current. The choke has a first and a second winding for connecting the heating element with the heating current supply. The choke comprises a third winding connected in parallel of the first and/or second winding. The capacitive detector is configured for measuring a portion of the alternating current flowing across the third winding and for taking into account the measured portion of alternating current when producing the output.

Abstract: A plural-frequency capacitive occupancy sensing system comprises an antenna electrode and a detection circuit, which is configured to drive the antenna electrode at least with a first and a second signal at a first and a second frequency, respectively, so as to obtain at least a first and a second measurement value indicative of at least one of conductance, susceptance, resistance, reactance and capacitance between the antenna electrode and a reference node, at the first frequency and the second frequency, respectively. The detection circuit compares the capacitance between the antenna electrode and the reference node with a threshold capacitance, the threshold capacitance being derived from a difference between the first and second measurement values and/or the capacitance between the antenna electrode and the reference node being corrected based upon the difference between the measurement values. The detection circuit outputs an occupancy state signal depending on the comparison.

Abstract: A method for capacitive sensing comprises the steps of tagging a transmitting signal by modulating a sub-carrier on said signal using state of the art modulation techniques; demodulating said subcarrier out of useful/received signal to prove validity of said signal.

Abstract: A capacitive detection device (20) for a vehicle comprises a sensing electrode (26) for generating an oscillatory electric field in a detection space and a shielding electrode (28) arranged on a side of the sensing electrode turned away from the detection space. The capacitive detection device comprises a circuit ground and a ground connector for connecting the circuit ground to chassis ground of the vehicle. At least one shunt capacitor is connected between circuit ground and the shielding electrode. The at least one shunt capacitor has a capacitance at least 25 times higher than the capacitance between the shielding electrode and the chassis ground of the vehicle.

Abstract: A capacitive occupant detection system comprises at least one antenna electrode to be arranged in a seat and an evaluation unit operatively coupled to said at least one antenna electrode, said evaluation unit being configured for applying, during operation, an alternating voltage signal to said antenna electrode and for detecting an amplitude and/or phase of a displacement current flowing from said antenna electrode towards ground. According to the invention said antenna electrode comprises an antenna electrode conductor and at least one dedicated ground electrode, said ground electrode being arranged at a predetermined distance of said antenna electrode conductor and extending along said antenna electrode conductor.

Abstract: A method of operating a differential mobility spectrometer includes an ionization chamber, a filter channel and a detection region. In the ionization chamber, analyte ions are produced from a sample, the so-obtained ions are then subjected in the filter channel to a time-varying electric field. The time-varying electric field has a longitudinal field component drawing the analyte ions from the ionization chamber through the filter channel into the detection region and a transversal field component, which is the superposition of an asymmetrically oscillating transversal field causing the analyte ions to move to and fro in transversal direction and a compensation field for selecting a species of analyte ions by substantially canceling the average transversal velocity of the selected species.

Abstract: A capacitive occupant detection system comprises at least one sensing electrode to be arranged on the bottom side of a seat cushion, a seat heater like structure to be arranged on a top side of said seat cushion, and an evaluation unit operatively coupled to said at least one sensing electrode for determining a value representative of the capacitance between the at least one sensing electrode and the seat heater like structure.

Abstract: A sheet-type ohmic heating element (10) comprises a substrate sheet (12) having applied thereon a layer of PTC material (14) and a protective cover sheet (16) laid over the layer of PTC material. The protective cover sheet extends beyond the boundary of the layer of PTC material and is affixed to the substrate sheet circumferentially around the boundary of the layer of PTC material. The protective cover sheet and the layer of PTC material are arranged in non-adhesive contact with each other.

Abstract: An automotive vehicle has arranged therein a vehicle seat and is equipped with an occupant detection system for detecting whether an occupant is present on the vehicle seat, the system including a first antenna electrode arranged in the seat and a first sensing circuit associated with the seat, where the first sensing circuit includes an oscillation circuit operatively connected to the first antenna electrode for applying to the first antenna electrode a first oscillating signal and a first current detection circuit connected to the first antenna electrode for determining a current flowing into the first antenna electrode in response to the first oscillating signal being applied thereto, where the current flowing in the first antenna electrode indicates whether an occupant is present on the vehicle seat, and when in operation, the first sensing circuit codes the information whether an occupant is present on the vehicle seat into a first output signal which is output and which may be supplied to a restraint sy

Abstract: A flexible heater and/or electrode comprises a woven textile material having a warp direction and a weft direction, said textile material comprising at least one region having a low electrical conductance and at least two regions having a high electrical conductance. The at least two regions of high electrical conductance are adjacent to said at least one region of low electrical conductance. At least one of said at least two regions of high electrical conductance is operatively connected to a connection terminal of said heater and/or electrode, said connection terminal for connecting said heater and/or electrode to an electronic control circuit.

Abstract: A pressure-responsive B-surface seat occupancy sensor unit for detecting an occupancy state of a seat comprises a pressure sensor arranged on a base plate. The pressure sensor includes a printed circuit board having a first surface with at least two electrodes and a second surface, with which the PCB is arranged on the base plate, and a membrane element arranged in facing relationship with and spaced from the electrodes so as to deflect under pressure and establish an electrical contact between the electrodes. The base plate includes one or more fixation elements, by means of which the base plate is fixable to the structural frame, the seat cushion and/or the cushion-supporting springs of the seat.

Abstract: A gas detector (100) for remote gas detection in a target region (106) comprises a light source (102) for emitting a light beam (110) into the target region and a light sensor (112) for sensing light returning therefrom. The light beam is wavelength-modulated around an absorption wavelength of the gas. A controller (108) is operatively connected to the light sensor for detecting a presence of the gas on a path of the light beam based on returning light sensed by the light sensor. An indicator (124) that is operatively connected to the controller indicates the presence of the gas. A scanning device (104) is arranged with respect to the light source so as to scan the light beam through the target region, and with respect to the light sensor so that the light sensor receives the returning light via the scanning device. The indicator cooperates with the scanning device to indicate a position of the gas in the target region.

Abstract: A film-type pressure sensor includes a carrier structure including a first carrier film, a second carrier film and a spacer film arranged between the first and second carrier films, where one or more pressure-sensing cells are disposed in the carrier structure, each of which includes an electrode arrangement for producing an impedance change in response to a compressive force, an electrical interface is provided for mechanically and electrically connecting the pressure sensor to an evaluation circuit, where some terminals of the interface are connected with the electrode arrangements of the cells so as to allow them to be read out, such that one or more electrical components interconnect at least two of the terminals in pairs so as to form a combination of terminal pair impedances that represents coded information relating to the pressure sensor.

Abstract: A combined seat heater and capacitive occupancy sensor comprises a heater network and a capacitive sensing network. The heater network includes a heating element (10) connected between a first node (21) and a second node (22) to dissipate heat. The capacitive sensing network is connected to the heating element to apply an oscillating current thereto and to derive a capacitive load of the heating element from the voltage resulting on the heating element. The heater network comprises a common mode choke (16) connecting the first and the second node to a third (23) and a fourth (24) node, respectively. The capacitive sensing network further comprises means to sustain the oscillating current in or to drive the oscillating current into the heating element as well as a high-impedance amplifier (32) having an input node operatively connected to the heating element to probe the resulting voltage, and an output node (44) to provide an output signal indicative of the voltage.

Abstract: In a combined seat heater and capacitive occupancy sensor, the present invention proposes to perform two measurements with two different frequencies. In a first step, the carrier frequency is set to a first known carrier frequency, the complex current through inductance and unknown capacitance and complex drive voltage are measured. In a second step, the carrier frequency is set to a second known carrier frequency, the complex current through inductance and unknown capacitance and complex drive voltage are measured. The measured complex values are used in a formula which yields the unknown capacitance.