Abstract: An oscillatory or pulsed first signal is operatively coupled to a first electrode placed between a conductive heating element and a seating region of a seat containing the heating element. A second signal substantially equal to the first signal is operatively coupled to a second electrode placed between the heating element and the first electrode. An occupant in the seat is sensed from a response to the first signal, responsive to which a safety restraint system may be controlled. In other embodiments, the second signal is operatively coupled to an electrode placed proximate to a side of the heating element away from the seating region of the seat, the second electrode comprises a sheath at least partially around at least a portion of the heading element, or the operative coupling of the first or second signals comprises AC coupling, for example, through an associated first or second capacitor.

Abstract: An anchor plate operatively coupled to a seat belt incorporates a slot that slideably engages an anchor bolt, which is biased therein by a spring. A tension in the seat belt causes a deflection of the spring and an associated motion of the anchor bolt in the slot, which is sensed by a proximity sensor on the anchor plate. In another aspect, a carriage is adapted to slide relative to a bracket, and a first spring is operative between the carriage and the bracket so as to bias the carriage relative to the bracket in a direction opposite to a first direction. Either the bracket is operatively coupled to a vehicle frame with an anchor bolt and the seat belt operatively engages the carriage, or vice versa. A tension in the seat belt, when reacted by the anchor bolt, causes an associated motion of the carriage in the first direction, which is sensed by a displacement sensor.

Abstract: An oscillatory or pulsed first signal is operatively coupled to a first electrode placed between a conductive heating element and a seating region of a seat containing the heating element. A second signal substantially equal to the first signal is operatively coupled to a second electrode placed between the heating element and the first electrode. An occupant in the seat is sensed from a response to the first signal, responsive to which a safety restraint system may be controlled. In other embodiments, the second signal is operatively coupled to an electrode placed proximate to a side of the heating element away from the seating region of the seat, the second electrode comprises a sheath at least partially around at least a portion of the heading element, or the operative coupling of the first or second signals comprises AC coupling, for example, through an associated first or second capacitor.

Abstract: An oscillatory or pulsed first signal is applied to a seat heating element that is operatively connected to first and second impedances that isolate the first signal from the source and sink of power to the heating element. In another embodiment, third and fourth impedances are connected to the first an second impedances at respective nodes, and a second signal substantially equal to the first signal is operatively coupled to the nodes. In another embodiment, the first signal is applied to an electrode, and the second signal is applied to the heating element, which shields the electrode from influence by the seat. In another embodiment, the first signal is applied to a first electrode that is shielded from the heating element by a second electrode operatively coupled to the second signal. The impedances may, for example, be provided by inductors or electronic switches.

Abstract: An anchor plate operatively coupled to a seat belt incorporates a slot that slideably engages an anchor bolt, which is biased therein by a spring. A tension in the seat belt causes a deflection of the spring and an associated motion of the anchor bolt in the slot, which is sensed by a proximity sensor on the anchor plate. In another aspect, a carriage is adapted to slide relative to a bracket, and a first spring is operative between the carriage and the bracket so as to bias the carriage relative to the bracket in a direction opposite to a first direction. Either the bracket is operatively coupled to a vehicle frame with an anchor bolt and the seat belt operatively engages the carriage, or vice versa. A tension in the seat belt, when reacted by the anchor bolt, causes an associated motion of the carriage in the first direction, which is sensed by a displacement sensor.

Abstract: An occupant detection system comprises an electric field sensor in the seat bottom of a vehicle seat for discriminating objects on the seat, and a seat weight sensor for sensing the force upon the seat. The electric field sensor discriminates normally seated occupants from other seating conditions, and disables a restraint actuator unless a normally seated occupant is present. The seat weight sensor disables the restraint actuator if force upon the seat is less than a threshold.

Abstract: An occupant sensor comprises an electric field sensor comprising a plurality of first electrodes mountable within a vehicle seat, wherein the plurality of first electrodes are disposed on a common surface and are non-overlapping with one another. The electric field sensor further comprises at least one second electrode, wherein the first and second electrodes are proximate to one another. A sensing circuit is operatively coupled to the first and second electrodes so as to control the level of capacitance between an occupant on said vehicle seat and the circuit ground. In a second aspect, the electric field sensor incorporates a lattice electrode with a ground plane. In a third aspect, the electric field sensor incorporates a receive electrode that receives a signal from a sensing electrode for purposes of mitigating the effects of a seat wetting condition.

Abstract: An occupant detection system comprises an electric field sensor in the seat bottom of a vehicle seat for discriminating objects on the seat, and a range/proximity sensor for sensing the presence of an object proximate to a restraint actuator. The electric field sensor discriminates normally seated occupants from other seating conditions, and disables a restraint actuator unless a normally seated occupant is present. The range/proximity sensor disables the restraint actuator if an occupant is located in an at-risk so as to be susceptible to injury by the restraint actuator.

Abstract: An occupant detection system comprises an electric field sensor in the seat bottom of a vehicle seat for discriminating objects on the seat, and a range/proximity sensor for sensing the proximity of an occupant's torso relative to the seat back of a vehicle seat. The electric field sensor discriminates normally seated occupants from other seating conditions, and disables a restraint actuator unless a normally seated occupant is present. The range/proximity sensor disables the restraint actuator if an occupant has not been proximate to the seat back for a period of time greater than a threshold.

Abstract: A sense electrode (12) is driven by a first oscillatory signal (26) and at least one control electrode (14) is driven by a second oscillatory signal (30). In first (38) and second (40) states (36), the second oscillatory signal (30) respectively has a first and second phase with respect to the first oscillatory signal (26). The proximity of an electric-field-influencing media (20) to the proximity sensor (10) is responsive to the difference of third (50) and fourth (52) signals that are respectively measured when the second oscillatory signal (30) is in respective first (38) and second (40) states. The proximity sensor (10) is calibrated with a known capacitance operatively coupled to the sense electrode (12) with a plurality of switches (S1, S2) adapted so that the switches (S1, S2) have a relatively small effect on the capacitance of the sense electrode (12).

Abstract: A first electric field sensor in a seat bottom identifies whether there is normally seated, forward facing occupant on a vehicle seat by generating an electric field and sensing the effect of proximate objects thereupon. A second electric field sensor determines if an object is within an at-risk zone proximate to a safety restraint system by sensing from a proximate location the electric field generated by the first electric field sensor, and is responsive to the degree to which an object detected in the at-risk zone is electrostatically coupled to the vehicle seat. A range/proximity sensor may be provided to measure the proximity of an occupant to the seat back, so as to accommodate occupant movement prior to the deployment of the safety restraint system, and to improve occupant discrimination.

Abstract: A sense electrode (12) and a plurality of control electrodes (14) are located proximate to a region of space (18) for sensing an object (20) therein. A first signal (26) and a plurality of second signals (30) respectively applied to the sense (12) and control (14) electrodes generate an electric field (16) within the region of space (18). The capacitance of the sense electrode (12) is measured for various electric field configurations responsive to the second signals (30) and to the proximity of the object (20). A most likely proximity scenario from a priori proximity scenarios is determined from the plurality of capacitance measurements. A front driven shield (36) is provided between the sense electrode (12) and the region of space (18) for selectively shielding the sense electrode (12) from influence by objects (20) or grounds, so as to provide for calibrating the measurement circuit (32) to compensate for parasitic capacitance and gain drift.

Abstract: An oscillatory or pulsed first signal is applied to a seat heating element that is operatively connected to first and second impedances that isolate the first signal from the source and sink of power to the heating element. In another embodiment, third and fourth impedances are connected to the first an second impedances at respective nodes, and a second signal substantially equal to the first signal is operatively coupled to the nodes. In another embodiment, the first signal is applied to an electrode, and the second signal is applied to the heating element, which shields the electrode from influence by the seat. In another embodiment, the first signal is applied to a first electrode that is shielded from the heating element by a second electrode operatively coupled to the second signal. The impedances may, for example, be provided by inductors or electronic switches.