WO2004065177A1

WO2004065177A1 - Elastic modulus modulation in seat pads and occupant classification via electroactive material

Info

Publication number: WO2004065177A1
Application number: PCT/US2004/001733
Authority: WO
Inventors: Joseph W. Mcelroy
Original assignee: Johnson Controls Technology Company
Priority date: 2003-01-22
Filing date: 2004-01-22
Publication date: 2004-08-05

Abstract

A seating material (10) for use in a cushion of a vehicle seat. The seating material includes polarizable elements (26) and a polarizing means (20, 22) to effect a polarizing field (24). The seating material may be coupled with a control circuit for selective activation of the polarizing field and alignment of the polarizable elements to adjust the properties of the material. Such seating material may be useful for occupant detection and/or classification.

Description

ELASTIC MODULUS MODULATION IN SEAT PADS AND OCCUPANT CLASSIFICATION VIA ELECTROACTIVE MATERIAL

BACKGROUND OF THE INVENTION

[0001] The present application relates to a seating material that responds to a polarizing field. The present application also relates to seating material that responds to a polarizing field and can be used in a seat for occupant classification.

[0002] Generally, automobile seats have included foam pads to provide comfort to the occupant. The foam pad commonly compresses and conforms to the body of an occupant. Often, the occupant desires a seat that more fully supports the occupant during driving conditions such as when cornering or traveling over rough terrain. Further, the preferred seating characteristics of the occupant commonly changes depending upon how long the occupant has been seated. Additionally, different occupants of the vehicle often desire different seat performance characteristics (e.g., stiffness levels). Traditional vehicle seats do not provide seating material that has the ability to respond to particular driving conditions. Further, conventional seating materials and seats do not allow a user/occupant to control actuation of the seat based upon the occupant's preferences.

[0003] Vehicle manufacturers are believed to begin demanding vehicles that include seats capable of effectively and reliably classifying an occupant. Occupant classification is not only important for occupant comfort, but also safety. Federal motor vehicle safety regulations increasingly mandate "smart vehicles" that are capable of detecting and/or classifying occupants, including the presence, position and/or size-stature of the occupant. Occupant classification can be used to prevent injury such as airbag-induced injury. A vehicle is needed that includes an effective and reliable occupant classification system which communicates with vehicle systems, such as safety systems.

SUMMARY OF THE INVENTION

[0004] To overcome the disadvantages, problems and limitations of current systems, it would be advantageous to provide a system and method for detecting and/or classifying an occupant in a vehicle. Desirably, the system and method is achieved by using materials having magnetic properties, such as an electroactive foam, that can be selectively manipulated by a power source. It is^' desirable to provide a system whereby the electroactive foam communicates with other vehicle systems to detect and/or classify the occupant, or alternatively, to adjust the electroactive material to provide additional comfort and/or support to the occupant.

[0005] Specifically, it would be desirable to provide a seating material of a type disclosed herein that includes elements which may be attracted to a polarizing field. Preferably, the seating material selectively resists conformational change resulting from force applied against the seat, such as forces resulting from an occupant or driving conditions. The seating material desirably resists conformational change by aligning some or all of the elements with the polarizing field. The seating material also alternatively includes at least one polarizing means dispersed within or adjacent to the seating material which provides the polarizing field.

[0006] It is also advantageous to provide a seat having the seating material described herein such that the seat is capable of detecting and/or classifying an occupant. In one embodiment, the seat communicates with a processor, which interprets the signals from the seat cushion material and sends an output signal to effect a vehicle system function or, alternatively, to another processor for additional processing. The seat is also designed to resist change or apply a reactive force against the occupant by activating the polarizing field through automatic or manually generated signals. The seat, together with the processing means and other vehicle systems, may also manage vibration within the car (i.e., the processing means are programmed to work in conjunction with the vehicle's suspension system to dampen or eliminate road vibrations normally felt by an occupant).

[0007] Alternatively, it is also desirable and advantageous to provide a vehicle that includes a seat described herein. For example, a vehicle with a seat that includes the seatmg material having polarizable elements can actuate and/or classify an occupant.

[0008] Further, it would be advantageous to provide a system and method for detecting and/or classifying an occupant in a vehicle that combines the seating material processing circuitry, and one or more sensors. A method for activating seatmg material by generating a polarizing field would also be advantageous.

[0009] The disclosure and teachings herein extend to those embodiments which fall within the scope of this disclosure and any appended claims, regardless of whether they accomplish one or more of the above-mentioned needs.

[0010] In one embodiment, the seat cushion material (such as, an expanded foam or latex foam cushion material) is modified to include polarizable elements, desirably providing an electroactive material. Thus, for shorthand purposes when the term seatmg material is used herein it should be understood that the inventor is referring to a seat cushion material including a polarizable element unless specifically stated otherwise. The polarizable elements may be distributed throughout the seating material, be located in particular regions of the seatmg material, or may be linlced (covalently, for example) to the seating material. As used herein, a polarizable element is any element that changes orientation in the presence of a polarizing field. An example of a polarizable element is a magnetic or electric dipole. Polarizable elements can also be paramagnetic or diamagnetic.

[0011] At least one first and second terminal pair is used to provide a polarizing field to activate the polarizable elements within the seat cushion material. The polarizing field can be an electric or magnetic field. When a polarizing field is created, the polarizable elements within the seat cushion material align with the polarizing field. While the polarizing field is in effect, the polarizable elements generally resist misalignment from the field and cause the seating material to resist conformational change, including compression. Depending on the strength of the polarizing field, the seating material may also actuate against an object applying force to the seat cushion material.

[0012] The pair of first and second terminals are located within the seating material and alternatively may be located adjacent but contacting the seatmg material such as connected to a surface of the seating material. There may also be a plurality of sets of first and second terminals to create proximate but distinguishable polarizing fields. When multiple sets of terminals are used, the sets of terminals may be arranged so that they are activated simultaneously or at different times. When activated simultaneously, the seatmg material within the fields created by the sets of terminals would resist change or actuate because the polarizable elements would align or attempt to align with the polarizing field. When the sets of terminals are activated at different times, different portions of the seating material may respond to the polarizing fields created by the activated terminals. [0013] The pair or sets of terminals may be coupled to a circuit, which may include a control circuit capable of receiving input signals from an input device and generating an output signal. The control circuit may be a digital and/or analog control circuit and can include a processor, a switch, and/or other control means. The control circuit desirably interprets the input signals in order to provide a desired output signal. Software or other code may be used to achieve this function. For example, the control circuit may include a processor loaded with software that processes an input signal and delivers an output signal to provide a polarizing field by closing the circuit between the first and second terminals. The processor may receive input signals from input devices including sensors and/or other control circuits controlled automatically or manually to indicate an event, such as, for example, detection of an occupant, suspension variation, or vehicle entry.

[0014] Also provided is a seat including seatmg material that includes polarizable elements and a polarizing means capable of providing a polarizing field. The polarizing means may be coupled with a control circuit for selective control of the polarizing means. For example, the control circuit may signal the polarizing means to activate or terminate the polarizing field, and/or vary the strength of the polarizing field. The seat may also include at least one sensor coupled with the polarizing means and control circuit (e.g., via an interface circuit). [0015] The seat described herein may be used in a vehicle. Vehicles commonly include vehicle systems such as, for example, a safety system that controls airbag deployment, ignition system, braking system, steering system and so forth. A vehicle system may also include the vehicle bus, that controls a number of different vehicle sub-systems. Desirably, at least one of the vehicle systems are coupled with the control circuit and is capable of providing an input signal to the control circuit. The control circuit may process the input signal and provide an output signal to the polarizing means. The output signal may be amplified or converted (e.g., digital to analog, analog^' to digital, etc.) before reaching the polarizing means as known in the art.

[0016] Also provided is a method of occupant classification with a seat having seating material that includes polarizable elements and at least one polarizing means that may selectively provide a polarizing field. The polarizing means may be coupled with a control circuit that controls current or voltage to the polarizing means. The control circuit may receive an input signal from an input device. The control circuit may also process the input signal and generate an output signal based upon the processed input signal. Typically, this may be done through software and any number of algorithms used to classify/detect the occupant based upon the input signals. The input device may be any number of devices including a sensor, control circuit, processor, or any other device that can generate a signal. The input device may also include a processor or other device (e.g., sensor) coupled to the circuit of the polarizing means. Preferably, an input device is used that detects a change in current in the circuit of the polarizing means, resulting in an input signal to the control circuit. Such a system may be capable to classify an occupant. The input devices may also be activated manually in addition to automatically (e.g., via smart sensors with processing circuitry). For example, a user can manually send an input signal to the control circuit by a switch means, such as a button or toggle switch. This may be desired when the user wishes to activate/deactivate the seating material.

[0017] A vehicle occupant classification system is also provided that includes an electroactive material having polarizable elements, at least one pair of first and second terminals to effect a polarizing field, and a processor connected to an input device. The processor may receive input signals from the input device and process the input signals to detect alignment of the polarizable elements. The processor may also generate an output signal to a vehicle system based upon the characteristics of the input signal and the software or other code used to process the input signal.

[0018] Also provided is an active seating material including seating material having polarizable elements and at least one pair of first and second terminals that provide a polarizing field. The polarizable elements are preferably paramagnetic elements dispersed within the seating material. The seating material may also include a shield, which can be used to block the magnetic field or direct access to the terminals. The first and second terminals may be coupled to a control circuit, desirably having a processing means. The control circuit may receive an input signal and provide an output signal, wherein the input signal delivers a message to the control circuit and the output signal delivers a message from the control circuit that selectively activates the first and second terminals to form the polarizing field.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The invention will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like parts.

[0020] Figure 1 is a schematic of seating material having two sets of terminals and polarizable elements, with one set of terminals emitting a polarizing field, in accordance with the teachings of the present application.

[0021] Figure 2A shows seating material in accordance with the teachings of the present application with no compressive force applied to the seating material and no polarizing field emitted from the terminals.

[0022] Figure 2B shows seating material in accordance with the teachings of the present application with compressive force applied and no polarizing field emitted from the terminals. [0023] Figure 2C shows seating material in accordance with the teachings of the present application with compressive force applied and a polarizing field emitted from the terminals.

[0024] Figure 3 is a block diagram of an active seating material system in accordance with the teachings of the present application.

[0025] Figure 4 is a block diagram of a seat system in accordance with the teachings of the present application.

[0026] Figure 5 shows several schematics of seating material having a plurality of terminals in accordance with the teaching of the present application.

[0027] Figure 6 is a block diagram of an occupant classification system in accordance with the teachings of the present application.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] A seatmg material is provided that desirably includes polarizable elements. The polarizable elements may be independent elements or may be linked to at least a portion of the seating material, e.g., the seating material may be constructed from polymers, molecules or molecular chains with polarizable element(s), natural fibers, etc. The polarizable elements may also be suspended and/or dispersed within the seating material. Non-exhaustive examples of the polarizable elements may include iron oxide, and/or microcapsules which encapsulate iron oxide or another polarizable element that may be used based upon the disclosure and teaching provided herein. Desirably, the polarizable elements are paramagnetic and do not retain a magnetic memory. An example of a commercially available polarizable element is BioMag from Polysciences, Inc., Warrington, Pennsylvania. The seating material may be constructed from a material that can cushion or absorb force, such as a foam padding, but may be constructed from other suitable materials known to those skilled in the art of seat foam. Alternatively, the seatmg material may be a laminate of different materials. Such materials with polarizable elements may be referred to herein as electroactive material.

[0029] Referring to FIG. 1, a seating material 10 is shown with polarizable elements 26 and two sets of a first terminal 20 and a second terminal 22. The sets of terminals may be activated to emit a polarizing field 24. An example of a polarizing field is magnetic or electric field. The two sets of terminals may be selectively activated as shown in FIG. 1. For example, one set of terminals may provide the polarizing field 24 and the other set of terminals may not provide a polarizing field. Alternatively, each set of tenninals may provide the polarizing field, hi other embodiments, the seating material may include one set of terminals or a plurality of sets of terminals. Each set of terminals may generate its own polarizing field. Although sets of terminals are described herein, the polarizing field may be formed by any polarizing means known in the art.

[0030] When the terminals 20 and 22 are activated and emit a polarizing field 24, polarizable elements 26 within the seating material align or attempt to align with the polarizing field 24. The alignment of polarizable element^'s 26 yields a modulus change in the seating material 10. The modulus change may result in seating material that resists conformational change or seatmg material that actuates against a force. The effect of the polarizing field on the polarizable elements is more clearly shown in FIGS. 2A-2C. FIG. 2 A illustrates seating material 10 when no compressive force is applied and no polarizing field is emitted from the terminals 20 and 22. When compressive forces 11 are applied to the seating material 10 without a polarizing field, the seatmg material 10 is fully compressed as shown in FIG. 2B. However, when the terminals 20 and 22 emit a polarizing field 24, the polarizable elements 26 align or attempt to align with the polarizing field 24 as shown in FIG. 2C. Under these circumstances, the polarizable elements 26 resist misalignment from the polarizing field 24 and, as a result, the seating material 10 resists conformational changes due to the compressive forces 11 and may even actuate against the compressive force 11. The terminals may be adjacent to, interspersed, intercalated, or enveloping within and around the seatmg material.

[0031] The terminals 20 and 22 may be coupled with a circuit as more clearly shown in a block diagram of the preferred polarizing field circuit in FIG 3. The polarizing field circuit may include a power source 30 that provides energy to the terminals 20 and 22. The circuit coupling the power source and terminals 20 and 22 may have a switch or other disconnect 32. When the circuit is open, no current may flow through the circuit and the terminals do not emit a polarizing field. When the switch is closed to complete the circuit, current may pass through the terminals to emit a polarizing field therebetween. The switch may be controlled by a control circuit 36 which receives an input signal from at least one input device 40 and provides an output signal 39. The output signal can be used to close or open the circuit to control the polarizing field between the first and second terminals. In some instances, it may be desirable to further amplify, convert or process the output signal. In other embodiments, the switch may be a variable switch that controls the amount of energy/current within the circuit. In such a scenario, the control circuit may be capable of adjusting the strength of the polarizing field as well.

[0032] The control circuit may be an analog or digital circuit, and may include a microprocessor or other processing means for analyzing the input signal. The control circuit may include other components such as a digital to analog and analog to digital converters, heat sinks, memory, and other processing and control means known in the art. Generally, the control circuit is programmed with software and/or algorithms to process the input signals. These algorithms may be specific to the input device 40 or may be general algorithms that convert the input signals to a desired output signal. For example, the control circuit may process an input signal to an output signal that tenriinates or activates the polarizing field. Other embodiments may include a control circuit with algorithms that vary the strength of the polarizing field. Yet other embodiments may include algorithms that direct the control circuit to provide an output signal to vehicle systems other than the seating material. [0033] The input signals may be generated from one or more input devices 40. The input device 40 may be a sensor, control circuit, or other vehicle system that is capable of generating an input signal. The input device may also collect data from different sources to generate the input signal. For example, in a vehicle system, the input device may collect information from ignition system, doors, steering, suspension, bumpers, accelerometer, brakes, or other vehicle systems capable of generating vehicle or occupant information. An example of such an input device would be a vehicle bus. The input device may also be individual sensors and/or control circuits that provide their own information to the control circuit 36 of the polarizing field circuit. For example, in one embodiment the input device may be a suspension system of a vehicle. The suspension system (suspension, sensor, processing means, etc.) may signal the control circuit when cornering, traveling over a bumpy road, or other similar situations. When the control circuit receives these input signals, it may activate the polarizing field and assist in occupant support (e.g., the control circuit may activate a set(s) of terminals on the bolsters of a seat and actuate against the occupant to maintain the occupant in a safe driving position) or generally help with vibration management.

[0034] In another embodiment, a vehicle having a seating system with electroactive material described herein may be used for occupant comfort. The seat may have numerous sets of terminals throughout the seat to activate the seating material. The occupant may depress a button or other switch means (input device) to provide a signal that activates all or a portion of the seat. Based upon the signal from the input device, the control circuit may activate a polarizing field in one area of the seat or throughout the entire seat. The control circuit may also provide output signals at intervals to different sets of terminals to activate the seating material at different times. This can provide a massaging effect, for example, where the seating material actuates against the occupant for varying periods of time and at varying time intervals.

[0035] In one embodiment, the suitable seatmg material may also be used to detect or classify occupants. In this regard, the polarizable elements may be used to determine whether an occupant is within the vehicle or may also be used to determine occupant presence, stature and/or other characteristics of the occupant. This may be more clearly shown in FIGs. 5 and 6. Generally, the change in bulk polarization alignment of the polarizable elements with the electrical field may be monitored to determine mechanical loading. Thus, the seatmg may be both a transducer and actuator for a myriad of applications and seating including occupant presence detection, occupant recognition, fatigue detection, occupant anthropometric classification estimation, seat service modification and other similar uses. [0036] In a preferred embodiment, for example, the input device may be at least one sensor coupled with the polarizing field circuit. The sensor may, for example, monitor the current between the first terminal 20 and the second terminal 22 and generate an input signal 38 to the control circuit 36. hi the preferred embodiment, the polarizing field is an electric field provided by a power source having an alternating voltage. The current flowing between the terminals can be measured by the formula:

I=C dV/dt « C ΔV/Δt where I is current, V is voltage, and C is interelectrode capacitance and t is time. Generally the voltage rate of change is a constant, while the current may vary. When no force is applied to the seating material, the polarizable elements align or attempt to align with the polarizing field and increase the capacitance through the seating material. The sensor may take a base reading of the highest current between the terminals to determine when the capacitance is greatest (e.g., when no force is applied). When force is applied to the seating material (e.g., when an occupant sits upon the seat), the force will work to misalign the polarizable elements from the polarizing field, resulting in a decrease in capacitance and a drop in current between the terminals. The sensor may generate input signals based upon shifts in current between the terminals 20 and 22, and the input signals 38 can be processed into output signals 39 that classify the occupant. For example, when the shift in current is small, the algorithm may indicate that a person of less than 50 pounds is within the seat and generate an output signal to vehicle safety systems, such as an airbag control system (e.g., an output signal to deactivate the airbags for that seat). An airbag control system generally includes an airbag processing circuit 50, a crash sensor 52, and an airbag 54. Airbag logic 50 can be a separate circuit from the control circuit 42 or may be integrated with control circuit and may be a portion of software or other code. Airbag control system is configured to receive data from the control sensor and to determine whether to fire¹ airbag and further configured to determine other parameters relating to the firing of airbag, such as, the fire power. Airbag logic may further be configured to receive other vehicle inputs from vehicle input source, such as, vehicle speed, and may be configured to utilize other vehicle data to control airbag. [0037] The system may include multiple circuits for a plurality of terminals. This can allow different sets of first and second terminals to be arranged throughout the seating material. Multiple circuits also allow the different sets of terminals to be activated simultaneously or at different times. When activated simultaneously, the entire seatmg material would resist conformation change because of the polarizable elements. This may be useful for the seat cushion or the bolsters. When the first and second terminal are activated at different times, different portions of the seat may actuate against the occupant. For example, the lumbar region may actuate against the spine, the seat back may provide a massaging. [0038] FIG. 4 illustrates a vehicle system having a vehicle seat 50 with a plurality of terminals situated therein. The vehicle may be an automobile or other vehicle, such as, a semi-trailer truck, a bus, a motorcycle, an aircraft, or other known vehicles. A block diagram of a vehicle occupant detection system shown in FIG. 4 includes a control circuit coupled to at least one input device. The input devices as previously disclosed may be any system capable of generating some information that can be delivered to the control circuit in an input signal such as ignition, door, buttons, etc. The input device may also be the vehicle bus, which controls information from multiple input devices, including safety systems (e.g., airbags, brakes), suspension, steering, or other vehicular functions. The input devices may each generate an input signal to the control circuit. The control circuit may also be coupled to a plurality of terminals 60 arranged throughout a seat.

[0039] The control circuit may include a processing means, such as a digital signal processor in an exemplary embodiment, but alternatively may be other types of analog and/or digital processing circuitry, such as, a microprocessor, a microcontroller, an application- specific integrated circuit (ASIC), programmable logic, etc., and may further include memory of the volatile and/or non- volatile type. The processing means receives the input signals from input device, such as a seat sensor, and provides an indication of the occupant. [0040] The seating material may be manufactured by interspersing the polarizable elements with the seating material components to provide a polarizable mixture. The polarizable mixture can be placed into a mold. Optionally, a particular arrangement of terminals may be placed within the mold prior to injection of the polarizable material. The terminals may be arranged in a wide variety of patterns including simple transverse arrangement, in sinuous arrangement, or helical arrangements. Alternatively, terminals may be placed on the outside- of the seating material after it has been molded. Additionally, the terminals may be interspersed through the seating material, arranged on the perimeter of the seating material or the combination of both. The seatmg material can be inserted within a seat. The seat may be a part of a vehicle including a car or airplane, or may be a part of any other seating means (e.g., chair, couch, etc.).

[0041] It may be desirable to include a member to shield the seating material and/or electric or magnetic fields. The member may be a coating composition, film, fabric or other material with either high electrical conductivity, high magnetic permeability or both. [0042] The features described herein and the details thereof are provided in exemplary form. Although only a few exemplary embodiments of the present invention have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible in these embodiments such as variations in the types of seats for which the present inventions is incorporated with, sizes, structures, shapes and proportions of the various elements, mounting arrangements, use of materials, combinations of shapes, etc. without materially departing from the novel teachings and advantages of the invention. For example, a seating material having polarized elements may be used in various components of a seatmg system such as a lower seat cushion, a seat back cushion, a headrest, a bolster, etc. Further, the vehicle systems that provide an input signal to the control circuit can include other vehicle systems in addition to those described herein.

[0043] While the exemplary embodiments illustrated in the FIGS, and described above are presently preferred, it should be understood that these embodiments are offered by way of example only. Accordingly, the present invention is not limited to a particular embodiment, but extends to various modifications that nevertheless fall within the scope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A seat system for use in a vehicle, the seat system comprising: a seat cushion comprising a first material having polarized elements therein; at least one set of terminals having a first terminal and a second terminal, the set of terminals operatively connected to the first material for providing a polarizing field for providing a modulus change in the first material of the seat cushion; and a circuit coupling a field generating source to at least one of the first terminal and the second terminal, the circuit further comprising a switch for selective activation of the polarizing field.

2. The seat system of claim 1, wherein the polarizing field is an electric field and the field generating source is a power source supplying a voltage to the first material.

3. The seat system of claim 1, wherein the polarizing field is a magnetic field and the field generating source is a power source supplying a current to the first material.

4. The seat system of claim 1, wherein at least one of the first terminal and the second terminal are located within the first material of the seat cushion

5. The seat system of claim 1, wherein at least one of the first terminal and the second terminal are located along a perimeter of the first material of the seat cushion.

6. The seat system of claim 1, further comprising an input device to provide a signal to the switch to activate the polarizing field.

7. The seat system of claim 6, wherein the switch is operatively coupled to a control circuit which receives an input signal from the input device and provides an output signal for selective activation of the polarized field.

8. The seat system of claim 1, wherein the input device is a vehicle system capable of generating an input signal.

9. The seat system of claim 8, wherein the vehicle system is at least one of a suspension system, a brake system, a steering system, an ignition system, a door system, an airbag system, a bumper system, and an accelerometer system.

1 10. The seat system of Claim 7, further comprising a plurality of sets of terminals.

1 11. The seat system of Claim 10, wherein the input device is a vehicle system

2 capable of generating an input signal and the input signal activates a first portion of the sets

3 of terminals to selectively affect a first portion of the first material of the seat cushion.

1 12. The seat system of Claim 10, wherein the input device allows a seat occupant

2 to selectively activate a first portion of the sets of terminals to selectively affect a first portion

3 of the first material of the seat cushion.

1 13. The seat system of Claim 10, wherein the control circuit provides the output

2 signal at intervals to different sets of terminals to activate the first material of the seat cushion

3 at different times.

1 14. A method for classifying a seat occupant, the method comprising:

2 providing a vehicle seat with a seat material having polarized elements

3 therein;

4 applying a polarized field to the seat material;

5 providing a sensor to monitor the polarized field;

6 using the sensor to capture a first reading representative of the polarized field

7 when a force is not being applied to the seat material by the seat occupant;

8 using the sensor to capture a second reading representative of the polarized

9 field when a force is being applied to the seat material by the seat occupant;

I o comparing the first reading with the second reading to generate an output

I I signal that classifies the seat occupant;

12 sending the output signal for operatively affecting at least one vehicle system.

1 15. The method of claim 14, wherein the polarizing field is applied by a set of

2 terminals having a first terminal and a second terminal and the method further comprises the

3 step of operatively connecting the first terminal and the second terminal to the seat material.

1 16. The method of claim 14, further comprising the steps of: selecting the

2 polarizing field as an electric field; and provided by a power source having a variable voltage.

17. The method of claim 14, further comprising the steps of: selecting the polarizing field as a magnetic field; and provided by a power source having an variable current.

18. The method of claim 14, wherein the step of using the sensor to monitor the polarized field further comprises the step of using the sensor to monitor a physical change in the polarized field.

19. The method of claim 14, wherein the step of using the sensor to monitor the polarized field further comprises the step of using the sensor to monitoring current flowing between the first terminal and the second terminal.

20. The method of claim 14, wherein the step of using the sensor to monitor the polarized field further comprises the step of using the sensor to monitoring voltage changes in the polarized field.

21. The method of claim 14, wherein the step of sending the output signal to the vehicle system further comprises the step of sending the output signal to at least one of a suspension system, a seatmg system, a steering system, an ignition system, a door system, and an airbag system.