Abstract: A child car seat with a built-in cushion switch that closes when the seat is occupied. Also, push type switches are added to at least one of the vehicle's side passenger doors with signals being routed to a micro-controller unit, which determines when the car seat is occupied AND when one of the doors is open and enables the vehicle's internal beeper alarm, thereby reminding any occupants exiting the vehicle that a child is strapped in the back seat. Additionally, an inside temperature sensor is coupled to the micro-controller unit, which sets off a loud external alarm such as the vehicle's security alarm, when the temperature inside the vehicle goes above or below a safe preprogrammed environmental range. This is an additional safety feature that will get the attention of people outside the vehicle, indicating that a child is trapped in a dangerous environment inside the vehicle and needs help.

Abstract: An occupant weight detecting device includes a load detector provided at a seat body and detecting load applied to the seat body and an occupant detector for detecting an occupant sitting on the seat body based on the load detected by the load detector. The occupant detector includes a load calculator for calculating the load based on a detected value detected by the load detector, a load area determination device for determining a load area by comparing the load with a predetermined threshold, and an occupant determination device for determining a type of occupant sitting on the seat body based on the load area.

Abstract: A system for measuring the weight of a seat occupant is used to control airbag deployment. The system is incorporated into a vehicle seat supported on inboard and outboard track assemblies. The inboard and outboard track assemblies are mounted to a vehicle structure such that a center track portion remains unsupported. A first sensor assembly is mounted to the inboard track assembly and a second sensor assembly is mounted to the outboard track assembly. The first sensor assembly generates a first signal in response to measuring deflection of the inboard track assembly due to seat occupant weight. The second sensor assembly generates a second signal in response to measuring deflection of the outboard track assembly due to seat occupant weight. A central processor determines seat occupant weight based on the first and second signals. The central processor communicates with the airbag system to control the deployment of the airbag based on seat occupant weight.

Abstract: An attachment structure for installing a load sensor to a vehicle seat includes the load sensor having a plate-shaped strain unit and a strain gauge for detecting a strain of the plate-shaped strain unit. The load sensor is structured that one end of the plate-shaped strain unit is fixed to a seating portion of the vehicle seat and the other end of the strain unit is fixed to a vehicle body. Also, a strain portion is defined between each fixed end of the plate-shaped strain unit, and the strain portion is deformable in a vertical direction relative to the vehicle seat. In addition, a load input point from the seating portion is defined approximately at a central portion of the strain portion of the plate-shaped strain unit.

Abstract: A detection device for an automobile seat includes a flexible pressure sensor having an upper face and a lower face, as well as a decoupling layer fixed on the lower face of the pressure sensor. The decoupling layer has a constant modulus of elasticity.

Abstract: A vehicle occupant sensing system for detecting a condition of a vehicle seat assembly having a lower seat cushion supported by a seat pan. The system has a tray with a plurality of pedestals disposed between the seat pan and the cushion. The system also has a plurality of sensor assemblies, each defining a force responsive axis and disposed between the lower seat cushion and tray. The pedestals support some of the sensor assemblies such that the force responsive axes of the sensor assemblies are substantially aligned with the occupant's weight load. Furthermore, the system may be employed in a seat assembly to detect a condition thereof. The tray allows addition of safety features in the vehicle seat assembly such that the seat more effectively retains the occupant, and yet the tray positions the sensor assemblies to be responsively aligned with the occupant's weight load despite these additional features.

Abstract: A computer shut down system includes a sitting detection assembly that is mounted in a seat cushion. The sitting detection assembly includes a pressure indicator for detecting when a weight is positioned on the seat cushion. A transmitter is operationally coupled to the pressure indicator. The transmitter is adapted for sending a wireless signal when the pressure indicator detects the weight. A receiver for receiving the wireless signal is electrically coupled to the computer processor such that the receiver may relay the wireless signal to the computer processor. The computer processor may selectively power down or power up the computer system upon reception of the wireless signal sent by the transmitter.

Abstract: An occupant weight detecting device includes a load detecting device and a control device. The load detecting device detects a load applied to a seat body. The control device detects an occupant sitting on the seat body based on a load detection value detected by the load detecting device. The occupant weight detecting device further includes a power supplying device for supplying power to the load detecting device and a memorizing device for memorizing the load detection value having been detected by the load detecting device. The control device performs primary filter calculation during a predetermined time based on the average of plural load detection values having been memorized to the memorizing device and a current load detection value. The control device performs secondary filter calculation after an elapse of the predetermined time based on one load detection value having been memorized to the memorizing device and the current load detection value.

Abstract: The present invention relates to a wheelchair and an underseat alarm system therefor.

Abstract: A passenger detection system is presented so that the master control circuit in the system instructs the passenger airbag control circuit controlling the operation of the airbag designated for the passenger seat to be in the deployable state or not-deployable state, depending on the seating conditions of a passenger sitting on the passenger seat, for example whether the passenger is an adult or a child.

Abstract: A seat cushion for a vehicle seat unit comprising a cushioning pad upholstered with a seat covering and a flexible but inelastic planar film with an electrically conductive element buried therein that is disposed between the cushioning pad and the seat covering. The cushioning pad has tuck-in grooves in which the seat covering is locally retained. The planar film is thickened at locations where the planar film transverses the tuck-in grooves for reinforcement.

Abstract: Method and arrangement for obtaining and conveying information about occupancy of a passenger compartment of a vehicle including at least one sensor for obtaining data from the passenger compartment. Information about the occupancy is generated based on the data and transmitted, e.g., through a cellular phone system, to emergency response personnel to enable them to respond accordingly. The information about the occupancy may be generated by a processor applying pattern recognition techniques so that any occupants of the seat may be classified and such classification transmitted to the emergency response personnel. The data may also be used to determine the number of occupants in the vehicle and/or whether the occupants are moving after a crash.

Abstract: In order to form a device for detecting and preprocessing weights acting on a vehicle seat in such a way that it can be used in particular in conditions which are very difficult in terms of measuring technology, and in particular under the other special ambient conditions within a vehicle, and the weighing signal of which is substantially uninfluenced by this and can consequently provide a reliable parameter for airbag activation, it is proposed that this device comprises at least three load cells, which are disposed on load-carrying parts of the vehicle seat at corner points of an imaginary polygonal area and in each case generate a weighing signal corresponding to the weight, and an electronic evaluation circuit, which receives and preprocesses the weighing signals of the load cells and generates an output signal based on the weighing signals, the evaluation circuit comprising an evaluation function with which a localization of the center of gravity of the weight acting on the vehicle seat can be carried ou

Abstract: A vehicle seat load measuring apparatus includes a base for bearing a load applied to the seat, an arm supported by the base for receiving the load, a load sensor supported by the arm for detecting the load, and a seat rail for guiding the seat in a longitudinal direction of the vehicle. The base is fixed to the seat rail so that an open face of the base faces in a downward direction. The arm is connected by a stopper pin inserted through holes in the base to a mounting bracket fixed to a vehicle body. The base bracket includes a load bearing portion and is attached to the base and fixed to the seat rail. The load bearing portion of the base bracket is configured to contact the stopper pin when a load exceeding a predetermined value is applied to the seat rail.

Abstract: The present invention is directed to a cushioning device. The present cushioning device has many attributes that are common with many cushions. Some of these common attributes are at least one bladder having a top surface, a bottom surface and at least one side surface positioned between the top and the bottom surfaces. Another common attribute is a bladder cavity being defined by the top surface, the bottom surface and the at least one side surface. The present invention differs from other bladders in that there is a first conductive material and a second conductive material are positioned within the bladder cavity, positioned away from the bottom surface of the bladder, and capable of acting like a switch for a reactive device. The reactive device is electrically interconnected with the first and second conductive materials. When the first and second conductive materials contact each other the reactive device is capable of responding by sounding an alarm and/or re-inflating the bladder cavity with a fluid.

Abstract: The present invention relates to a vehicle passenger detecting apparatus capable of detecting an unoccupied-seat state through the use of existing signals in a vehicle and correcting an unoccupied-seat reference value with a simple configuration. In a case in which an ignition key switch and a buckle switch are in off conditions and a load detecting value, which is the sum of measurement data from load sensors in these conditions, falls below a predetermined unoccupied-seat load value, an occupied-seat reference value serving as a load measurement standard for detection of a state of a vehicle passenger is corrected using the load detection value. This eliminates the influence of vibrations stemming from engine revolutions and electrical noises and enables the reference value to be corrected using a stabler load detection value.

Abstract: A Hall effect sensor assembly including a Hall effect sensor; an overmolded housing which is overmolded onto the Hall effect sensor; and a magnet movably connected to the Hall effect sensor by a movable connection with the overmolded housing. The movable connection restrains movement of the magnet to a path along and aligned with a Hall effect central sensing axis. The magnet is substantially prevented from tilting relative to the sensing axis.

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: This document discloses various systems and methods for reducing the likelihood of leaving an unattended child behind in an infant/child seat in a vehicle.

Abstract: An apparatus is provided for warning when a person such as an infant has been left in an infant seat in a vehicle and the operator of the vehicle has departed from the vehicle. The apparatus includes an occupant detection mechanism for detecting the presence of an occupant within a seat-belted seat located within a vehicle; optionally a mechanism for detecting the state of the vehicle's motion; a control unit for generating an alarm signal when the occupant detection mechanism detects the presence of an occupant within the infant seat and an alarm unit for generating an alarm in response to the alarm signal.

Abstract: In a passenger weight measuring apparatus, each of bend parts of front and rear brackets for supporting a seat to a vehicle main body side becomes bent and deformed in response to the load applied by the weight of the passenger sit in the seat. A load sensor on each the bend part detects the load based on the bend deformation and outputs a voltage signal of magnitude responsive to the load to a signal processor. The processor generates a load detection signal clamped in the voltage range corresponding to a preset passenger weight load range from the voltage signal and outputs the load detection signal to an output terminal. When the detected load is a collision load set in a load region out of the load range, the processor outputs an abnormal load detection signal different from the load detection signal to the same output terminal.

Abstract: An occupant classification system for recognizing the type of occupant of a motor vehicle seat especially for use in controlling an inflatable restraint system. The classification system utilizes a number of on-off electrical switches arranged in a pattern on a seat cushion mat. Signals from the switches may be processed in a variety of manners to characterize the occupant.

Abstract: A self contained patient sensing and monitoring system is provided for sensing and monitoring the presence, absence, and movement of the patient. Embodiments of the present invention provide a system conformable to a patient support surface, systems that are self contained, systems that are operationally unobtrusive, and programmable systems. Embodiments of the present invention comprise a container, a sensor configured within the container, and a control unit responsive to the sensor and configured within the container, wherein the container at least substantially encompassing the sensor and the control unit and wherein the control unit is conformable to the patient support surface. Some embodiments of the present invention comprise a container, a sensor configured within the container, and a control unit conformable to a patient support surface and configured within the container, wherein said control unit is responsive to the sensor.

Abstract: A timing pad for determining the amount of time used when consuming a beverage. The user places an object, such as a mug, glass, or bottle, onto the weight sensor area (2). The user then presses the reset button (4). The reset button (4) is connected to an internally located replaceable battery (14), which supplies power to the timer (7) and the weight sensor (8). The timer (7) and the weight sensor (8) are connected electrically to permit the timer (7) to begin running when user removes the object from the weight sensor area (2). When user places the object back onto the weight sensor area (2), the stop watch-like timer (7) stops running. The user may now remove the object to read his or her beverage consuming time in the timer display (1). The timing pad is particularly suited for beverage consumers desiring to know the precise amount of time it took to consume a beverage in comparison to others.

Abstract: A child safety seat comprises a safety seat unit. An alarm unit is coupled to the safety seat unit. The alarm unit sounds an alarm to remind occupants of the vehicle when a child is sitting in the child safety seat after the ignition of the vehicle in which the child safety seat is installed is turned off.

Abstract: Disclosed is a method for manufacturing a continuous-length switch that comprises first and second electrodes. The method comprises covering at least a first surface of a first electrode with an insulating material. Then, a portion of the insulating material from the first surface of the first electrode is removed so as to provide an exposed portion of the first electrode. And then, a second electrode is placed on the insulating material and over the exposed portion of the first electrode.

Abstract: Provided is a method and control system for a plurality of passenger seat belt mechanisms for appropriately securing and protecting passengers. The control system enables the flight crew to monitor and remotely control the locking and unlocking of passenger seat restraint mechanisms, thereby controlling the number of passengers, at any given time, having access to the aircraft cabin during flight. This control system is provided with a mechanism for collectively and selectively locking and unlocking the seat restraint mechanisms. The control system is capable of detecting and signaling the current state of a seat restraint mechanism.

Abstract: Weight sensor assemblies for measuring weight on a vehicle seat are mounted at the connecting points between a seat bottom frame and a seat mounting member. The weight sensor assemblies each include a beam member having a bendable center body portion for supporting a stain gage. The strain gage and associated traces are screen printed on the surface of the beam. The beam acts similar to a dual constrained cantilever beam, concentrating the bending at a reduced neck section that narrows in the middle of the center body portion. The strain gage measures strain resulting from bending in the center body portion caused by a weight force being applied against the seat.

Abstract: An operator presence sensing apparatus for a seat of a vehicle includes a base member (7, 8) for supporting the seat (6), and a relay member (9) extending vertically between the base member and the seat. The seat is oscillatable about a pivot axis (X) extending in a transverse direction in the base member. The relay member is pivotably supported at one end thereof by the pivot axis and at the other end by the base member through a cushion spring (10). A seat lift-up spring (12) is disposed between an underside of the seat and the base member for receiving part of the weight of the seat. The seat unoccupied by the operator is oscillated to a floating position lifted from the relay member by the lift-up spring.

Abstract: A vehicle seat assembly includes a sensor assembly that is used to provide data for an occupant classification system. The data is used to determine such characteristics as seat occupant weight and position. These characteristics are used to control deployment of a safety restraint mechanism such as an airbag. The sensor assembly is part of a mat that is placed on top of a foam cushion used to form a seat bottom. Various attachment methods can be used to permanently secure the mat to the foam cushion. Preferably, the mat includes mounting portions that are wrapped around the foam cushion to engage a bottom surface of the foam cushion. Fasteners, adhesives, hook and loop attachments, and other similar attachment members are associated with the mounting portions and are used in various combinations to secure the mat to the foam cushion.

Abstract: An apparatus is provided for warning when a child has been left in an infant car seat within a vehicle and the vehicle's door is opened to accommodate exiting driver. The apparatus includes an occupant detection mechanism for detecting the presence of an occupant within an infant seat located within a vehicle; a light detection component for detecting the state of the vehicle's dome light; a battery which provides power to the apparatus; an alarm which activates when the occupant detection mechanism detects the presence of an occupant within the infant seat and the light detection component detects the vehicles dome light has gone from an “off” state to an “on” state because the driver opened the door to exit vehicle. Components of the apparatus are located within the infant seat and can move from vehicle to vehicle along with the infant seat or from infant seat to infant seat.

Abstract: An improved force-measurement system utilizes active magnetostrictive sensors for generating a signal representative of a force, such as the weight of a person or thing on a seat within a motor vehicle, or the force applied to the horn sensor switch on a vehicle steering wheel. The active magnetostrictive sensor includes an excitation coil and a detection coil.

Abstract: A device for classifying persons or objects, in particular for occupant classification in a motor vehicle, includes an arrangement for acquiring characteristic data on the person to be classified or the object to the classified; at least one algorithm for extracting features from the instantaneously acquired characteristic data; at least one filter for determining the classification of the person or the object from the instantaneously extracted features, taking into account the time progression of the features extracted for the person to be classified or the object to be classified; and a first counter for initiating the resetting of the filter when the algorithm, during the first time interval specified by the first counter, has exclusively provided features for the non-presence of a person or an object, so that the resetting behavior of the algorithm, or the filter downstream from the algorithm, may be decoupled from the output of the determined classification in a simple manner.

Abstract: An identification device for retrofitting a child seat is provided for detecting the child seat on a vehicle seat in a motor vehicle by means of a child seat detection device. A transceiver component, connected to a control and evaluation device, for transmitting an electromagnetic transmission signal and for receiving an electromagnetic reception signal, is arranged as part the child seat detection device in the vehicle seat or in the direct vicinity of the vehicle seat. The reception of the transmission signal in the identification device causes transmission of the reception signal. The identification device has external wiring. By means of a defined mechanical manipulation which brings about a defined change in the external wiring, the identification device can be changed from an inactive initial state to an active state.

Abstract: The resistances of resistors arranged in a matrix form in a pressure-sensitive resistor mat are measured with high accuracy and using simple circuitry by the fact that the output of an operational amplifier is connected to each row conductor and each column conductor, which are connected to the resistor. A voltage is selectively applied to the individual resistors by appropriately activating the operational amplifiers. Each operational amplifier associated with the row or column conductors is equipped with a current balancing circuit which detects the output current of the operational amplifier connected to the selected resistor which flows through this resistor. A processor determines the individual resistance values from the currents flowing through the individual resistors and the voltage drops across those resistors.

Abstract: A vehicle occupant sensing system that includes a sensor assembly. The sensor assembly has a housing that includes a base and an upper slide member. The upper slide member is moveable toward and away from the base. A sensor is operatively fixed relative to at least one of the upper slide member and the base and is operable to detect movement of the upper slide member toward and away from the base. Additionally, the vehicle occupant sensing system includes a variable biasing member adapted to bias the upper slide member away from the base with a force that is non-linearly related to movement of the upper slide member toward and away from the base. The vehicle occupant sensing system of the present invention may be employed in a vehicle seat assembly to detect a condition of the vehicle seat assembly.

Abstract: A seat weighing device wherein a load transmitting member for transmitting the seat load to a load sensor is formed without extremely high precision required, thereby enabling simple manufacturing of the load transmitting member. The seat weighing device includes a base having an arm for transmitting the seat load to a load sensor. The arm does not include a V-shaped portion, but includes only a single action portion. The single action portion is mounted to a sensor plate for mounting the load sensor so as to transmit the seat weight from the single action portion to the sensor plate. The arm includes only the single action portion, thereby suppressing irregularities in transmission of the load.

Abstract: A vehicle occupant sensing system including a circuit carrier, an electric circuit with leads, and a sensor with a body and a plurality of formed terminals. Each of the terminals has a lower portion spaced a predetermined distance away from a plane defined by the bottom surface of the body. Moreover, the system has a plurality of conductive connectors each including a blade extending into the circuit carrier and into electrical communication with a lead of the electric circuit. The body is supported on the circuit carrier, and the terminals are supported by the top end of the connector. Also included is a method of manufacturing the same. The formed terminals allow the sensor to be more easily positioned relative to the connector, thereby facilitating assembly. Also, the connectors support the terminals when the connector attaches to the terminal, thereby inhibiting damage to the terminals that could otherwise occur.

Abstract: A vehicle occupant sensing system for detecting a condition of a vehicle seat assembly having a lower seat cushion supported by a seat pan. The system has a tray with a plurality of pedestals disposed between the seat pan and the cushion. The system also has a plurality of sensor assemblies, each defining a force responsive axis and disposed between the lower seat cushion and tray. The pedestals support some of the sensor assemblies such that the force responsive axes of the sensor assemblies are substantially aligned with the occupant's weight load. Furthermore, the system may be employed in a seat assembly to detect a condition thereof. The tray allows addition of safety features in the vehicle seat assembly such that the seat more effectively retains the occupant, and yet the tray positions the sensor assemblies to be responsively aligned with the occupant's weight load despite these additional features.

Abstract: A vehicle occupant sensing system for detecting a condition of a vehicle seat. The system includes a circuit carrier, an electric circuit with a plurality of leads, and at least one sensor that has a plurality of terminals. Also, the system includes a plurality of conductive connectors associated with the corresponding terminals and leads. The connectors each include a body disposed for electrical communication with the associated terminal and include at least one deformable blade. The blade extends into the circuit carrier and into electrical communication with the associated lead of the circuit, thereby mechanically attaching the conductive connector to the carrier while providing electrical communication between the sensor and the circuit. Also included is a method of manufacturing the same. By piercing the carrier and the circuit, the blade establishes a more robust mechanical and electrical connection for the sensor, thereby increasing the operating life of the system.

Abstract: A low profile sensor assembly for use in a vehicle occupant sensing system that comprises a base, an upper slide member, and at least one intermediate guide member. Also disclosed is a low profile sensor assembly for use in a vehicle occupant sensing system that comprises a base with an outer step and a receptacle, and the low profile sensor assembly also comprises an upper slide member with a lower flange and a retainer. The outer step is adapted to accept the lower flange, and the receptacle is adapted to accept the retainer. The intermediate guide member, the outer step, and the receptacle each allow the respective upper slide member to move further toward the base. Thus, when the low profile sensor assembly is incorporated into a vehicle seat assembly, the low profile sensor assembly is less likely to detrimentally affect the comfort level of the vehicle seat assembly.

Abstract: A sensor assembly for use in a vehicle seat cushion for detecting the presence of an occupant includes a mat adapted to be installed in the vehicle cushion. The mat includes first mounting structure and a first sensor device attached to the mat. A first member has a second mounting structure adapted to be attached to the first mounting structure for attaching the first member to the mat. A second member is movably mounted relative to the first member about an axis. A second sensor device is mounted in the second member.

Abstract: The invention relates to a weight monitoring system for a motor vehicle (1) which can, if appropriate, be connected to a trailer (2). The system uses weight sensors to determine the weights (F1, F2) acting on the axles of the motor vehicle, in order to calculate from them the overall weight of the vehicle, and the axle loads. In addition, a tractive force sensor may be provided in the trailer hitch so that the mass of the trailer (2) can be determined by means of the tractive force (F3) and the acceleration of the vehicle. The weight monitoring system calculates various weight variables from the measured values and monitors to determine whether they remain within defined limits. In this context, it is possible, in particular, to take into account a planned route in such a way that the limiting values of the charge are adapted with respect to the maximum altitude (Hmax) above sea level and/or the maximum gradient (smax) of the route.

Abstract: A seat occupation is judged with a load detector arranged at a seat for detecting a load on the seat and a seat condition detection means arranged at the seat for providing discrimination between an adult and a child seat on the seat. A judging means judges that a child seat is set on the seat when the load detection means detects the load corresponding to that of adult and the seat condition detection means detects that the child seat on the seat. The seat condition detection means may comprise an electrostatistic sensor for detecting a capacitance that is increased by the body of the passenger or a pressure detection element array arranged on the sitting portion. The detected capacitance or the pressure distribution is different between a child seat and an adult or a passenger.

Abstract: The seat structure includes a torsion bar as an elastic supporting-mechanism for elastically supporting a cushioning member, and is provided with arms and a supporting frame pivoted by the torsion bar. Accordingly, a device for determining a load on the seat can be structured with an extremely simple structure by providing a displacement detecting mechanism to detect the amount of twist or the twist angle of the torsion bar, or a pivot angle of the arm, displaced by being seated.

Abstract: A vehicle occupant classification system categorizes vehicle occupants into various classes such as adult, child, infant, etc. to provide variable control for a vehicle restraint system such as an airbag. The classification system utilizes sensors that are installed in various locations in the vehicle. The sensors are used to generate a three-dimensional profile for the vehicle occupant. Various factors can affect the accuracy of this three-dimensional profile. Fuzzy logic is used to reduce some of the inaccuracies by providing multiple decision levels for various stages of the classification. Inaccuracies are also caused by sensors shifting within the system from their original position. This condition creates offset and the system evaluates this offset and generates a correction factor to provide a more accurate three-dimensional profile.

Abstract: A vehicle seat load measuring apparatus includes a base for bearing a load applied to the seat, an arm supported by the base for receiving the load, a load sensor supported by the arm for detecting the load, and a seat rail for guiding the seat in a longitudinal direction of the vehicle. The base is fixed to the seat rail so that an open face of the base faces in a downward direction. The arm is connected by a stopper pin inserted through holes in the base to a mounting bracket fixed to a vehicle body. The base bracket includes a load bearing portion and is attached to the base and fixed to the seat rail. The load bearing portion of the base bracket is configured to contact the stopper pin when a load exceeding a predetermined value is applied to the seat rail.

Abstract: A child detection system includes a warning system for detecting the presence of a child in a vehicle. The vehicle has a front seat area, a rear seat area, and an interior. The system comprises a plurality of pressure sensors each removably positioned selectively under one or both of the front and rear seat areas such that pressure on one of the seat areas actuates an associated one of the pressure sensors. A control is electrically coupled to an electrical power supply and is electrically coupled to each of the pressure sensors. The control is selectively coupled to the electric system of the vehicle such that the processor may detect when the vehicle is turned off. An alarm is operationally coupled to the control and emits an audible sound when any of the pressure sensors sense pressure. The control is turned on when the vehicle is turned off.

Abstract: A system including piezoelectric material wherein a force exerted on the piezoelectric material is determined by subjecting the piezoelectric material to an input signal of sweeping frequency and evaluating the response of the piezoelectric material to the applied signal.

Abstract: The invention concerns a device for detecting (10) a vehicle seat (12) comprising a flexible pressure sensor (14) and a decoupling layer (16) fixed on the lower surface of the pressure sensor (14), said decoupling layer comprising a module with constant elasticity. In a preferred embodiment, the decoupling layer (16) comprises an open structure with a bottom layer (20) and a spacing structure (18) provided on said bottom layer.