In an example, a vehicle seat sensor system includes a vehicle seat, a flexible seat sensor, and an electronics unit. The vehicle seat includes a seat surface. The flexible seat sensor is disposed within a deformable distance from the seat surface and includes one or more signal electrodes, one or more ground electrodes, one or more dielectric layers, and one or more capacitors. Each capacitor is formed by a combination of a corresponding signal electrode and a corresponding ground electrode with a corresponding dielectric layer positioned between the corresponding signal electrode and the corresponding ground electrode. The electronics unit is connected to the flexible seat sensor and is configured to electrically communicate with the flexible seat sensor. The flexible seat sensor is configured to provide a capacitive output proportional to an amount of pressure applied to the flexible seat sensor.

An occupant support includes a vehicle seat and a sensor system coupled to the vehicle seat. The sensor system is configured to measure capacitance data of an occupant of the vehicle seat.

A method and circuit for measuring impedance of a sense-only capacitive sensor operated in loading mode. The method carried out by the circuit includes the steps of: combining a plurality of synchronized output signals; applying low-pass filtering to the summed output signals to generate a sinusoidal test signal; applying the sinusoidal test signal to a sensor signal voltage divider circuit and to a reference voltage divider circuit; determining amplitude and relative phase, with respect to the sinusoidal test signal, of a sensor voltage signal and a reference voltage signal; obtaining a difference voltage signal by subtracting the reference voltage signal from the sensor voltage signal; and feeding the difference voltage signal to a vector demodulator unit for obtaining a real part and an imaginary part of the complex impedance of the capacitive sensor.

The present disclosure relates to a method for determining the occupancy status of a seat of a motor vehicle, the method being implemented by a determination system comprising a seat, six interdigitated capacitive sensors, and a controller comprising a reference capacitance value and a threshold value for each interdigitated capacitive sensor, the method comprising a step of measuring three capacitance values for each interdigitated capacitive sensor, the following steps being implemented by the controller for the measured capacitance values: calculating a resulting capacitance value based on the measured capacitance values, calculating the difference between the resulting capacitance value and the reference capacitance value, comparing the calculated difference to the threshold value, determining the occupancy status of the seat, based on the result of the comparison.

A capacitance measurement circuit for determining a capacitance of a guard-sense capacitive sensor includes a microcontroller that uses a combination of several synchronized PWM outputs for generating a low distortion sine wave. The sine wave is used as a guard voltage for the guard electrode of the capacitive sensor. The capacitance value of an unknown capacitor is measured by impinging the guard voltage on the sense electrode of the capacitive sensor by a modified sigma-delta modulator unit. The digital output of the sigma-delta modulator unit is first multiplied by an XOR gate before being routed into a decimator/low pass filter. The second input of the XOR gate is driven by a square wave from a square wave generator with the same frequency as the guard voltage, but with a substantially 90? phase shift. The output of the decimator/low pass filter is indicative of the capacitance value of the unknown capacitor.

Vehicular control method to avoid collisions in which a smartphone is coupled to the vehicle while in a vehicular compartment. Data is generated from vehicle-resident sensors about operation of the vehicle and transferred from the vehicle to the smartphone while the smartphone is coupled to the vehicle. A communications network with another vehicle is established using the smartphone and the data transferred from the vehicle to the smartphone and data from sensors on the smartphone is transmitted via the smartphone and established communications network to other vehicle, the data including data about location and movement of the vehicle. Then, while the smartphone is coupled to the vehicle, a vehicular operational function is controlled based in part on data transmitted using the smartphone and established communications network to cause movement of the vehicle to change in order to avoid a collision with the other vehicle.

A vehicle alarm system for inhibiting a passenger from being left in a vehicle includes a vehicle has a processor, a pair of rear seats, a theft alarm and door locks. The processor selectively generates an alarm sequence and the processor is electrically coupled to the theft alarm and the door locks. A plurality of pressure sensors is each positioned within an associated one of the rear seats. Each of the pressure sensors detects when a passenger is seated in the associated rear seat. The processor generates the alarm sequence when the vehicle is turned off and at least one of the pressure sensors detects the passenger in the associated rear seat. Moreover, the theft alarm is turned on when the processor generates the alarm sequence to alert that at least one passenger remains in the vehicle thereby inhibiting the passenger from is injured by heat exposure.

A capacitance measurement circuit for determining a sense current of a capacitive sensor with a sense electrode and a guard electrode. The measurement circuit includes a periodic signal voltage source, a sense current measurement circuit configured for determining the sense current with reference to a reference voltage, and at least one remotely controllable switch member. In a first switching state, the at least one switch member electrically connects the sense current measurement circuit to the periodic signal voltage source for providing a first reference voltage, and in a second switching state, the at least one switch member electrically connects the sense current measurement circuit to a second reference voltage that is different from the first reference voltage.

A system for detecting the presence of an occupant of a seat. The system includes a sensing mat that includes an upper conducting layer and a lower conducting layer. At least one of the conducting layers comprises a printed electronic circuit separated into conductive zones by at least one resistive zone. The mat also includes a plurality of sensing zones and each of the sensing zones include a conductive zone from the upper conducting layer and a conductive zone from the lower conducting layer. Each of the conducting layers are connected to a controller configured to detect a change in capacitance of each of the sensing zones resulting from a change in distance between the upper conducting layer and the lower conducting layer. The controller is connected to a vehicle network and is configured to provide data to the network that indicates the absence or presence of the occupant.

A vehicle alarm system for inhibiting a passenger from being left in a vehicle includes a vehicle has a processor, a pair of rear seats, a theft alarm and door locks. The processor selectively generates an alarm sequence and the processor is electrically coupled to the theft alarm and the door locks. A plurality of pressure sensors is each positioned within an associated one of the rear seats. Each of the pressure sensors detects when a passenger is seated in the associated rear seat. The processor generates the alarm sequence when the vehicle is turned off and at least one of the pressure sensors detects the passenger in the associated rear seat. Moreover, the theft alarm is turned on when the processor generates the alarm sequence to alert that at least one passenger remains in the vehicle thereby inhibiting the passenger from is injured by heat exposure.