Abstract: A seat assembly is provided that can be sat upon by an occupant that detects the weight of the occupant. The seat assembly includes a seat cushion, a rotary sensor, and a linkage having a tip. The seat cushion deforms in response to the weight. The rotary sensor has a shaft that rotates about an axis and has an electrical output that is proportional to the angle of rotation of the shaft. The linkage underlies the seat surface and connects the seat surface to the shaft of the rotary sensor. As weight is placed on the seat the seat cushion deforms in response to the weight moving the tip and the linkage. The movement of the linkage rotates the shaft, which in turn, provides an electrical output that is proportional to the weight.

Abstract: An occupancy detection system includes a signal generator coupled to an electrode, the signal generator configured to output a first signal at a first frequency and a second signal at a second frequency. The system further includes a voltage detection circuit connected to an output terminal of the signal generator and to an input terminal of the electrode, wherein the voltage detection circuit is configured to measure a first voltage responsive to the first signal at the first frequency and a second voltage responsive to the second signal at the second frequency. A control module in communication with the voltage detection circuit is configured to detect a state of occupancy based on the first voltage and the second voltage.

Abstract: A vehicle crash event is detected and characterized based on the transmission of acoustical shear waves through the vehicle frame. At least three, and preferably four or more, acoustical emission sensors longitudinally and laterally distributed on the vehicle frame produce acoustical signals that are processed to extract the shear wave energy due to impacts. Since shear waves are non-dispersive and travel through the vehicle frame at a known velocity, they can be detected in any part of the frame. The extracted shear wave signals are used not only to judge the severity of the impact, but also to characterize the type of crash and determine the direction of the impact based on when the shear wave is detected by each of the acoustical emission sensors.

Abstract: A seat assembly is provided that can be sat upon by an occupant that detects the weight of the occupant. The seat assembly includes a seat cushion, a rotary sensor, and a linkage having a tip. The seat cushion deforms in response to the weight. The rotary sensor has a shaft that rotates about an axis and has an electrical output that is proportional to the angle of rotation of the shaft. The linkage underlies the seat surface and connects the seat surface to the shaft of the rotary sensor. As weight is placed on the seat the seat cushion deforms in response to the weight moving the tip and the linkage. The movement of the linkage rotates the shaft, which in turn, provides an electrical output that is proportional to the weight.

Abstract: A occupant detection system includes an electronic device in communication with a sensor. The system detects an occupant by way of measuring an impedance of an electric field emitted by the sensor. The electronic device is configured to acquire data values from an output signal of the sensor, and reduce the effect of transient electrical interference on the acquired data values and adapt for sustained electrical interference on the acquired data values. A method includes acquiring a new data value, determining whether the new data value represents transient interference, and capturing the new data value if the new data value is free of transient interference and rejecting the new data value if the new data value represents transient interference.

Abstract: A seat assembly including a seat cushion, a heating element, a heating circuit, a occupant sensing circuit, and an isolation circuit. The seat cushion has a seating surface, the heating element is adjacent the seating surface and is formed of electrically conductive material. The heating circuit is coupled to the heating element for supplying electrical current to the heating element for generating heat. The occupant sensing circuit is also coupled to the heating element for sensing the presence of an occupant near the heating element. The isolation circuit is interposed between the heating circuit and the heating element for isolating the heating circuit from the occupant sensing circuit.

Abstract: An occupancy detection system includes a signal generator coupled to an electrode, the signal generator configured to output a first signal at a first frequency and a second signal at a second frequency. The system further includes a voltage detection circuit connected to an output terminal of the signal generator and to an input terminal of the electrode, wherein the voltage detection circuit is configured to measure a first voltage responsive to the first signal at the first frequency and a second voltage responsive to the second signal at the second frequency. A control module in communication with the voltage detection circuit is configured to detect a state of occupancy based on the first voltage and the second voltage.

Abstract: An occupant detection system includes an electrode in communication with a detector circuit that detects the impedance of the electrode and compensates for environmental conditions, such as humidity or moisture, based on the impedance measurement. Such environmental conditions may interfere with the occupant detection system's ability to detect the presence and/or size of an occupant. Typically, environmental conditions change the impedance of the electrode. The impedance is determined by measuring a frequency response of the electrode. The measured frequency response is compared to predetermined frequency response values that correspond to known environmental conditions. The environmental condition may be detected by matching the peak frequency response or average frequency response to in a lookup table.

Abstract: An ultrasonic sensing system includes an ultrasonic transmitter, an ultrasonic receiver, a processor and a memory subsystem. The transmitter is positioned to transmit an ultrasonic signal into a predetermined volume. The receiver is positioned to receive a composite signal from the predetermined volume. The processor is coupled to the transmitter, the receiver and the memory subsystem. The memory subsystem stores code that when executed by the processor instructs the processor to perform a number of steps to determine whether an occupant is present in the predetermined volume and whether the detected occupant has a respiration rate.

Abstract: A cargo sensing apparatus for a cargo container such as a semi-trailer includes a laser line scanning unit. In a preferred embodiment, first and second laser line generators are mechanically scanned in synchronism with a solid-state imager to identify and map the contents of the cargo container. The map is analyzed to detect cargo items stored in the container, and the cargo status is reported to a remote location.

Abstract: A child restraint system with a child seat monitoring system and a method for monitoring a child seat are provided. The child restraint system is adapted to be mounted within a vehicle. The child restraint system includes a child seat having a carrier portion and a handle coupled to the carrier portion. The child restraint system further includes a temperature sensor disposed on the handle for generating a first signal indicative of a temperature in a predetermined region of the child seat.

Abstract: A vehicle crash event is detected and characterized based on the transmission of acoustical shear waves through the vehicle frame. At least three, and preferably four or more, acoustical emission sensors longitudinally and laterally distributed on the vehicle frame produce acoustical signals that are processed to extract the shear wave energy due to impacts. Since shear waves are non-dispersive and travel through the vehicle frame at a known velocity, they can be detected in any part of the frame. The extracted shear wave signals are used not only to judge the severity of the impact, but also to characterize the type of crash and determine the direction of the impact based on when the shear wave is detected by each of the acoustical emission sensors.

Abstract: A synchronous demodulation circuit uses a digitally controlled track-and-hold circuit to capture the peak amplitude of a rectified signal. A microcontroller controls the track-and-hold circuit. In particular, the microcontroller controls a hold mode of the track-and-hold circuit to capture the peak amplitude of the rectified signal.

Abstract: A universal, compartment-wide system identifies the presence and position of occupants of a multi-place vehicle by utilizing the occupants to conduct and radiate place-specific radio frequency signals that are received at various locations in the passenger compartment. The place-specific radio frequency signals are developed by low power transmitters disposed in the various seat/place locations, and a receiver disposed at a central location that is remote from the transmitters receives and decodes the signals radiated by the occupants to determine the number and location of the occupants. Additional receivers may be installed in specified regions to detect occupant intrusion into such regions, and in various control panels to assess driver distraction and to tailor the functional content and capability depending on whether a driver or non-driver is interacting with the control panel.

Abstract: The capacitance of a shielded capacitive load cell is determined so as to minimize the effect of stray or parasitic capacitance between the load cell and other objects including the shield. The load cell conductors are coupled across input and output terminals of an operational amplifier that is tied to a reference voltage. A constant current is applied to the load cell, and the resulting rate of change in voltage at the amplifier output is measured as a representation of the load cell capacitance. In a vehicle seat sensor application including an electromagnetic interference shield between the load cell and the seating surface, the amplifier output is coupled to the load cell electrode furthest from the shield, the amplifier maintains the other load cell electrode at a virtual reference voltage, and the shield is tied to the reference voltage.

Abstract: A capacitive load cell apparatus includes upper and lower capacitor plates and an intermediate dielectric in the form of a synthetic knit spacer material having upper and lower fabric layers interconnected by an array of deflectable synthetic fibers. When occupant weight is applied to the seat, the synthetic fibers deflect to locally reduce the separation between the upper and lower capacitor plates, and the consequent change in capacitance is detected as a measure of the applied weight. The load cell or just the dielectric may be encased in a polymeric sheath to prevent intrusion of foreign matter, and a fluid such as silicone may be dispersed in woven dielectric.

Abstract: An ultrasonic occupant detection and classification system transmits an ultrasonic signal and receives a composite signal containing interference created between the transmitted ultrasonic signal and a reflection of that signal from a moving occupant. A signal component of the received, composite signal is extracted by amplitude demodulation and bandpass filtered to derive a frequency characteristic that is compared to stored frequency data; and the derived and stored data are compared to identify frequencies characteristic of respiration and/or other movements characteristic of living beings.

Abstract: A fluid-filled seat bladder assembly includes multiple capacitive sensing elements for detecting variation in bladder deformation due to occupant weight. The bladder is defined by upper and lower elastomeric sheets that are peripherally sealed by welding, and the capacitive sensors are defined by metalized films adjoining the upper and lower elastomeric sheets. The bladder fluid separating the upper and lower metalized films acts as a dielectric material, and the capacitance or electric field coupling of each sensor increases when the separation between the respective upper and lower films decreases due occupant seat weight. The cumulative change in capacitance or electric field coupling reflects the total seated weight, and the individual capacitance or electric field coupling changes provide a profile of the pressure distribution across the seat for improved occupant classification.

Abstract: A sensor including at least two active areas for receiving light energy and a resistive layer disposed on each of the at least two active areas for providing a pair of current signals corresponding to a position of light energy of a predetermined wavelength striking the active area. The two or more active areas are electrically isolated from each other and operate independent of each other. Preferably, the two or more active areas are electrically isolated with silicon dioxide.

Abstract: An ultrasonic occupant detection and classification system transmits an ultrasonic signal and receives a composite signal containing interference created between the transmitted ultrasonic signal and a reflection of that signal from a moving occupant. A signal component of the received, composite signal is extracted by amplitude demodulation and bandpass filtered to derive a frequency characteristic that is compared to stored frequency data; and the derived and stored data are compared to identify frequencies characteristic of respiration and/or other movements characteristic of living beings.