Techniques are disclosed for systems and methods to detect and/or classify a vehicle occupant, such as a passenger seated within the cockpit of a vehicle. An occupant classification system includes an occupant weight sensor, an occupant presence sensor, and a logic device configured to communicate with the occupant sensors. The occupant weight sensor includes at least first and second conductive electrodes separated by a dielectric layer, top and bottom protective plastic layers configured to support the respective first and second conductive electrodes, and adhesive layers disposed between the plastic layers and the conductive electrodes and between the conductive electrodes and the dielectric layer. The top protective plastic layer is longer and/or wider than the first conductive electrode and the bottom protective plastic layer is longer and/or wider than the second conductive electrode to provide edge protection against electrical shorts for the first and second conductive electrodes.

A capacitive sensor member (130) of a vehicle seat occupant detection and classification device (18) comprises a first electrically conductive antenna member (132) and at least a second electrically conductive antenna member (134) that is adjacently arranged to the first electrically conductive antenna member (132) without any mutual galvanic connection. At least one electrically conductive bridging member (146) is fixedly attached to at least one elastic spacer member (148) that has elastic mechanical properties in a specified direction (54). If a mechanical load (F) is applied to the capacitive sensor member (130) in the specified direction (54) that is equal to or larger than a predetermined value for the mechanical load (F), the at least one electrically conductive bridging member (146) provides at least one galvanic contact between the first electrically conductive antenna member (132) and the second electrically conductive antenna member (134).

A capacitive sensor device configured for being connected between an electric heating member and a heating current supply and for using the electric heating member as an antenna electrode. The sensor device includes a common mode choke for connecting between the heating member and the current supply, and a control and evaluation circuit for determining an electrical impedance between the electric heating member and a counter electrode via a measurement node. The control and evaluation circuit includes: a third winding inductively coupled to the first and second windings of the common mode choke, a periodic signal voltage source directly connected to the third common mode choke winding, an electrical quantity measurement circuit configured to determine an electrical quantity across the measurement node, and an EMI filter network that is connected across a signal input port of the third winding and a reference input port connected to AC ground potential.

Aspects of the disclosure relate to apparatus and methods for unattended occupant protection system (UOPS) safety systems for passenger vehicles. The UOPS safety system may include a UOPS module. The module may be integrated with a vehicle data bus of the passenger vehicle. The module may be in communication with a plurality of UOPS sensors. The module may launch an equalization mode in response to determining, via the UOPS sensors, the presence of an unattended occupant in the passenger vehicle with a high or rising ambient temperature. The equalization mode may stabilize the ambient temperature of the passenger vehicle.

An impedance measurement circuit for determining a complex impedance of a capacitive sensor that is configured for employing at least one electric heater member as an electrode to be operated in loading mode. The measurement circuit includes: a signal generating unit for providing an electric measurement signal; a signal sensing circuit measuring current through the at least one electric heater member; an electric heater member connection circuit comprising a plurality of MOSFETs for selectively electrically connecting the electric heater member either to the signal sensing circuit for complex impedance measurement or to a DC electric power unit for heating purposes; and a control and evaluation unit that is configured for controlling a switching status of the plurality of MOSFETs according to a predefined sequence, and for determining a complex impedance from the determined currents with reference to a complex reference potential during predefined stages of the predefined sequence.

An occupant or object sensing system in a vehicle includes electrical circuits for resistive and/or capacitive sensing and corresponding circuits shielding the sensing system from interference. A sensing circuit and a shielding circuit may be printed by screen printing with conductive ink on opposite sides of a non-conductive substrate. The substrate is a plastic film or other fabric that has an elastic memory structure that is resilient to stretching. The conductive inks used to print circuits onto the substrate have a similar resilience to stretching such that the substrate and the circuits thereon can be subject to deforming forces without breaking the printed circuits. The substrate may be covered with a carbon polymer layer to provide alternative conductive paths that enable fast recovery for conduction in the presence of any break in the printed conductive traces on the substrate.

An impedance measurement circuit for determining a sense current of a guard-sense capacitive sensor operated in loading mode. The circuit includes a periodic signal voltage source for providing a periodic measurement voltage, a sense current measurement circuit, a differential amplifier that is configured to sense a complex voltage difference between the sense electrode and the guard electrode, a demodulator for obtaining, with reference to the periodic measurement voltage, an in-phase component and a quadrature component of the sensed complex voltage difference, and control loops for receiving the in-phase component and the quadrature component, respectively. An output signal of the first control loop and an output signal of the second control loop are usable to form a complex voltage that serves as a complex reference voltage for the sense current measurement circuit.

A capacitive detection system for detecting occupancy of a vehicle seat includes a signal generating unit and a signal evaluation unit. The vehicle seat has a seat heater member configured for receiving pulse-width modulated electrical heater power of a pulse-width modulation frequency and time-varying output signals of the signal generating unit. The signal evaluation unit is configured to monitor a voltage difference between the electrical connection ends of the seat heater member, and is further configured to generate an output signal that is indicative of the seat heater member to be defective, on the basis of a fulfillment of at least one predetermined condition concerning the monitored voltage difference and a phase of the pulse-width modulated electrical heater power.

In addition to the loading mode of a capacitive sensing device of a seat occupancy detection and classification system, a second measurement mode is introduced, which allows a discrimination of objects (CRS or human) with and without grounding condition. Depending on the value of the new measurement, the data is allocated to different groups which are subject to different thresholds in the loading mode. This means that if the new measurement indicates a grounding condition of the object, a higher threshold in the loading mode will be applied. In this way CRS with grounding condition will be classified by means of the higher threshold, resulting in a robustness increase. Typical human sitting positions do not show a grounding condition and will be classified by the lower threshold.

A method is provided for controlling a vehicle seat, wherein settings of parts of the vehicle seat are dynamically adjusted depending on person-related parameters of the person seated on the seat, to make the seated position of the person as favorable as possible under biomechanical aspects.