WO1998030411A1 - Systeme capteur de poids pour siege d'automobile - Google Patents
Systeme capteur de poids pour siege d'automobile Download PDFInfo
- Publication number
- WO1998030411A1 WO1998030411A1 PCT/US1998/000252 US9800252W WO9830411A1 WO 1998030411 A1 WO1998030411 A1 WO 1998030411A1 US 9800252 W US9800252 W US 9800252W WO 9830411 A1 WO9830411 A1 WO 9830411A1
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- Prior art keywords
- occupant
- weight
- seat
- vehicle seat
- sensors
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R21/00—Arrangements or fittings on vehicles for protecting or preventing injuries to occupants or pedestrians in case of accidents or other traffic risks
- B60R21/01—Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents
- B60R21/015—Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents including means for detecting the presence or position of passengers, passenger seats or child seats, and the related safety parameters therefor, e.g. speed or timing of airbag inflation in relation to occupant position or seat belt use
- B60R21/01512—Passenger detection systems
- B60R21/01516—Passenger detection systems using force or pressure sensing means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
- B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
- B60N2/002—Seats provided with an occupancy detection means mounted therein or thereon
- B60N2/0021—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement
- B60N2/0024—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement for identifying, categorising or investigation of the occupant or object on the seat
- B60N2/0025—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement for identifying, categorising or investigation of the occupant or object on the seat by using weight measurement
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
- B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
- B60N2/002—Seats provided with an occupancy detection means mounted therein or thereon
- B60N2/0021—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement
- B60N2/0024—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement for identifying, categorising or investigation of the occupant or object on the seat
- B60N2/0027—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement for identifying, categorising or investigation of the occupant or object on the seat for detecting the position of the occupant or of occupant's body part
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
- B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
- B60N2/002—Seats provided with an occupancy detection means mounted therein or thereon
- B60N2/0021—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement
- B60N2/003—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement characterised by the sensor mounting location in or on the seat
- B60N2/0033—Seats provided with an occupancy detection means mounted therein or thereon characterised by the type of sensor or measurement characterised by the sensor mounting location in or on the seat mounted on or in the foam cushion
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R21/00—Arrangements or fittings on vehicles for protecting or preventing injuries to occupants or pedestrians in case of accidents or other traffic risks
- B60R21/01—Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents
- B60R21/015—Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents including means for detecting the presence or position of passengers, passenger seats or child seats, and the related safety parameters therefor, e.g. speed or timing of airbag inflation in relation to occupant position or seat belt use
- B60R21/01512—Passenger detection systems
- B60R21/01516—Passenger detection systems using force or pressure sensing means
- B60R21/01522—Passenger detection systems using force or pressure sensing means using fluid means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G19/00—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups
- G01G19/40—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups with provisions for indicating, recording, or computing price or other quantities dependent on the weight
- G01G19/413—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups with provisions for indicating, recording, or computing price or other quantities dependent on the weight using electromechanical or electronic computing means
- G01G19/414—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups with provisions for indicating, recording, or computing price or other quantities dependent on the weight using electromechanical or electronic computing means using electronic computing means only
- G01G19/4142—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups with provisions for indicating, recording, or computing price or other quantities dependent on the weight using electromechanical or electronic computing means using electronic computing means only for controlling activation of safety devices, e.g. airbag systems
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
- B60N2210/00—Sensor types, e.g. for passenger detection systems or for controlling seats
- B60N2210/40—Force or pressure sensors
- B60N2210/44—Force or pressure sensors using fluids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
- B60N2230/00—Communication or electronic aspects
- B60N2230/30—Signal processing of sensor data
Definitions
- Co-pending U.S. Application Serial No. 222 hereinafter "Application ASL-157-US” , entitled “Seat Weight Sensor Having Fluid Filled Bladder” , filed on December 18, 1997 claiming benefit of U.S. Provisional Application Serial No. 60/032,380 filed on December 19, 1996, and assigned to the assignee of the instant invention discloses a hydrostatic weight sensor comprising a fluid filled bladder and a pressure sensor for sensing the weight of an occupant in a vehicle seat for controlling a safety restraint system.
- Application ASL- 157-US also discloses a load distributor for distributing loads across the load bearing surface of the hydrostatic weight sensor.
- the instant invention generally relates to sensors and systems for measuring weight and more particularly to a weight sensor for measuring the weight of occupants and other objects in a motor vehicle seat such as useful for determining occupant seating conditions for controlling a vehicle safety restraint system.
- a vehicle may contain automatic safety restraint actuators which are activated responsive to a vehicle crash for purposes of mitigating occupant injury.
- restraint actuators include air bags, seat belt pretensioners, and deployable knee bolsters.
- an automatic safety restraint system mitigates occupant injury, thereby not causing more injury with the automatic restraint system than would be caused by the crash had the automatic restraint system not been activated. Notwithstanding the protective benefit of these automatic safety restraint actuators, there is generally both a risk and a cost associated with the deployment thereof. Generally, it is desirable to only activate automatic safety restraint actuators when needed to mitigate injury because of the expense of replacing the associated components of the safety restraint system, and because of the potential for such activations to harm occupants. This is particularly true of air bag restraint systems, wherein occupants too close to the air bag at the time of deployment - i.e.
- out-of-position occupants are vulnerable to injury or death from the deploying air bag even when the associated vehicle crash is relatively mild.
- occupants who are of small stature or with weak constitution, such as children, small adults or people with frail bones are particularly vulnerable to injury induced by the air bag inflator.
- infants properly secured in a normally positioned rear facing infant seat (RFIS) in proximity to a front seat passenger-side air bag are also vulnerable to injury or death from the deploying air bag because of the close proximity of the infant seat's rear surface to the air bag inflator module.
- RFIS normally positioned rear facing infant seat
- air bags are designed to protect vehicle occupants
- conventional crash detection and safety restraint deployment systems only use sensors which are mounted on the vehicle frame and are triggered by acceleration or velocity of the car rather than the occupant.
- Air bag inflators are designed with a given restraint capacity, as for example, the capacity to protect an unbelted normally seated fiftieth percentile occupant when subjected to a 30 MPH barrier equivalent crash, which results in associated energy and power levels which can be injurious to out-of-position occupants. While relatively infrequent, cases of injury or death caused by air bag inflators in crashes for which the occupants would have otherwise survived relatively unharmed have provided the impetus to reduce or eliminate the potential for air bag inflators to injure the occupants which they are intended to protect.
- One technique for mitigating injury to occupants by the air bag inflator is to reduce the power and energy levels of the associated air bag inflator, for example by reducing the amount of gas generant in the air bag inflator, or the inflation rate thereof. This reduces the risk of harm to occupants by the air bag inflator while simultaneously reducing the restraint capacity of the air bag inflator, which places occupants a greater risk for injury when exposed to higher severity crashes.
- Another technique for mitigating injury to occupants by the air bag inflator is to control the rate of inflation rate or the capacity of the inflator responsive to a measure of the severity of the crash.
- the risk of injury to such occupants would not be mitigated under the conditions of higher crash severity when the inflator is intentionally made aggressive in order to provide sufficient restraint for normally positioned occupants.
- Yet another technique for mitigating injury to occupants by the air bag inflator is to control the activation of the air bag inflator responsive to the presence, position, and size of the occupant, or to the severity of the crash.
- the air bag inflator can be disabled if the occupant weight is below a given threshold.
- the inflation capacity can be adjusted by controlling the number of inflation stages of a multi-stage inflator that are activated.
- the inflation power can be adjusted by controlling the time delay between the firings of respective stages of a multi-stage inflator.
- One measure of restraint capacity of an air bag inflator is the amount of occupant kinetic energy that can be absorbed by the associated air bag system, whereby when the occupant collides with the gas filled air bag, the kinetic energy of the occupant is converted to potential energy via the pressurization of the air bag, and this potential energy is dissipated by venting pressurized gases from the air bag.
- the velocity of an unrestrained occupant relative to the vehicle increases.
- the occupant restraint process is commenced early in the crash event so as to limit the amount of occupant kinetic energy which must be absorbed and thereby minimize the associated restraint forces and accelerations of and loads within the occupant.
- an occupant weight sensor is useful in an air bag system with variable restraint capacity to enable the restraint capacity to be preferentially adapted to the weight, or mass, of the occupant.
- Occupant presence can be detected by a seat weight sensor adapted to provide either a continuous measure of occupant weight or to provide a binary indication if the occupant weight is either above or below a specified weight threshold.
- Known seat weight sensors comprise one or more pads employing force sensitive resistive (FSR) films. These arrangements are typically used as weight threshold systems to disable a passenger air bag when the seat is empty. Load cells attached to the seat mounting posts have also been used in research applications. Mechanisms which use string based potentiometers to measure downward seat displacement have also been investigated.
- FSR force sensitive resistive
- variable resistance force sensors have limited sensitivity and in some situations are not sensitive enough to put directly under a seat pad while still achieving the desired response.
- the threshold weight system provides only very limited information. For example, such arrangements provide no indication as to the size of an occupant.
- the resistance values of known variable force resistor change with temperature, and are subject to drift over time with a constant load on the sensor.
- optical or infrared sensors have been used to measure the spatial position of occupants relative to the dashboard or headliner. Often these sensors are also integrated with speed sensors to discern changes in occupant position due to car acceleration. Current optical and infrared occupant position sensors require augmented information from speed and weight sensors, thereby resulting in a relatively high cost distributed system which may be difficult to manufacture, install, and maintain. Furthermore, optical and/or infrared sensors which measure the range from the headliner or dashboard can be confused by placement of objects in front of an occupant, such as when reading newspapers or books, or by the position of the seat back because many seats can recline fully back and incline fully forward. Moreover, the sensing aperture of these sensors may become occluded by inadvertent scratching or substance application.
- the prior art also teaches the use of seat weight sensors outside the automotive environment, for example as a means for disabling the activation of either a boat or an industrial machine if the operator is not properly seated, or for weighing a person seated on an exercise bike.
- These devices employ pneumatic bladders located in the seat, whereby the pressure within the bladder is used to either activate a threshold switch or to provide a continuous indication of occupant weight.
- a pneumatic seat weight sensor Another problem with a pneumatic seat weight sensor is that the sensor bladder must be sufficiently thick to prevent the top and bottom surfaces of the bladder from compressing against one another responsive to a sufficiently great localized or concentrated load under conditions when the bladder has a relatively small amount of gas, such as would occur when the bladder is filled at low pressure or high temperature.
- a gas filled bladder is also prone to loss of fluid by leakage or osmosis, which necessitates a means for replenishing the working fluid of the bladder over the life of operation.
- the prior art also teaches the use of hydraulic load cells, wherein the weight to be measured acts upon a piston element of known area, whereby the measured weight is found by multiplying a measured pressure times the known area.
- hydraulic load cells in the automotive environment, particularly in a seat, is that the effects of load cell orientation on hydraulic head can introduce load measurement errors.
- the present invention overcomes the above-noted problems by providing a seat weight sensing system which determines the weight, stature, and distribution of occupant weight on an automobile seat and seat back prior to and during a frontal, side, or rear-end collision.
- This sensor data can be used to augment conventional crash detection data such as generated by an accelerometerto optimize air bag deployment and minimize or avoid occupant injury.
- a hydrostatic weight sensor comprises a deformable confinement that contains a fluid, wherein the deformable confinement may constitute either a distinct chamber, or one chamber of a multi-chamber deformable confinement.
- the hydrostatic weight sensor further comprises either a pressure sensor operatively coupled to the deformable confinement for sensing the pressure of the fluid contained therein, or an means for operatively coupling a pressure sensor to the deformable confinement.
- the hydrostatic weight sensor may also comprise one or more of the following elements: 1 ) a means for replenishing the fluid within the deformable confinement, 2) a means for releasing excessive fluid from the deformable confinement, or 3) a means for regulating the amount of fluid within the deformable confinement.
- the fluid contained by the deformable confinement may comprise either a gas, a liquid, a Bingham fluid, or a thixotropic material.
- Various types of pressure sensors may be incorporated into or associated with the hydrostatic weight sensor in accordance with the instant invention.
- the pressure sensor may sense either the absolute pressure of the fluid within the deformable confinement, or the difference between the pressure thereof and the local atmospheric pressure.
- the pressure sensor may be either internal or external to the hydrostatic weight sensor, may be integrated therewith or separated therefrom, and may operate on any principles known to one of ordinary skill in the art, including the measurement of strain in the surface of the deformable confinement, or the measurement of pressure through the surface of the deformable confinement whereby the pressure sensor is isolated thereby from the fluid.
- a load distributor comprises a means for distributing the load applied to a hydrostatic weight sensor across one or more load bearing surfaces of the hydrostatic weight sensor.
- a hydrostatic weight sensor is preferably partially filled with fluid, particularly for fluids such as gases that are subject to expansion under the influence of ambient temperature and pressure conditions.
- a partially filled hydrostatic weight sensor is susceptible to bottoming out under the influence of concentrated loads unless a means is provided for distributing the applied load across the load bearing surfaces of the hydrostatic weight sensor.
- the seat cushion inherently acts as a load distributor but is subject to localized deformation under the influence of loads that are sufficiently great or sufficiently concentrated.
- a load distributor preferably is both sufficiently rigid to prevent concentrated loads from causing localized deformations of sufficient magnitude to locally collapse the hydrostatic weight sensor, and sufficiently flexible so as to not interfere with seating comfort. Examples of various load distributors in accordance with the instant invention are disclosed in Applications ASL-157 and ASL-186 referenced hereinabove and incorporated herein by reference
- a hydrostatic weight sensor is provided in a vehicle seat, wherein a bladder is formed within the cushion of the seat, as for example by molding the seat cushion with an internal cavity or by bonding mating pieces of seat cushion material together whereby each piece is scalloped in the bonding plane so that when the mated pieces are bonding together, the scalloped regions of the seat cushion material form an internal cavity.
- the cavity is filled with a fluid, which is preferably air.
- a pressure sensor operatively coupled to the internal cavity senses the pressure of the fluid therein, whereby a load applied to the seat cushion deforms the cavity thereby decreasing the associated volume and increasing the pressure of the fluid therein, responsive to the magnitude of the applied load.
- the weight of the applied load is measured by an associated signal processor responsive to the signal from the pressure sensor.
- a hydrostatic weight sensor system for sensing the weight on an occupant in a vehicle seat, wherein a bladder is formed from a flexible material and further comprises a plurality of distinct chambers, each of which contains a fluid and each of which is operatively coupled to an associated pressure sensor that senses the pressure of the fluid in the associated chamber.
- the pressure sensors preferably sense the difference between the pressure of the fluid and the local atmospheric pressure.
- the hydrostatic weight sensor system is incorporated in the vehicle seat, preferably below the seat cushion foam.
- the pressure of the fluid in each chamber is responsive to the associated component of occupant weight that is supported by the associated chamber of the bladder, whereby the associated plurality of pressure measurements provides a measure of the distribution of occupant weight on the seat, which is useful for calculating the position or stature of the occupant on the vehicle seat.
- a plurality of hydrostatic weight sensors are incorporated in the base of the vehicle seat proximate one another so as to provide an associated plurality of pressure measurements, whereby each associated pressure measurement is responsive to the component of weight supported by the associated hydrostatic weight sensor.
- the occupant weight distribution within the seat is determined from the plurality of pressure measurements, from which the associated occupant position is calculated.
- the hydrostatic seat weight sensors may be either laterally or longitudinally proximate one another so as to sense either the lateral or longitudinal distribution of occupant weight respectively from which the respective lateral or longitudinal occupant position is calculated.
- the overall weight applied to the seat can be calculated as the sum of the weight components sensed from the separate hydrostatic weight sensors.
- a plurality of hydrostatic weight sensors are incorporated in a vehicle seat, whereby at least one the hydrostatic weight sensors is located in the seat bottom, and at least another of the hydrostatic weight sensors is located in the seat back, whereby the stature or position of the occupant is calculated from the separate weight measurements.
- the instant invention provides a means for sensing an occupant's weight and weight distribution so as to enable the associated control of a safety restraint system.
- the weight distribution information can be used to determine the occupant's position on the seat.
- the instant invention also provides a means for distinguishing rear or forward facing infant seats, and small occupants from full size adults.
- the system of the instant invention can be easily and economically manufactured and installed in most existing or future seat designs, such as pan or spring, by merely modifying the size, shape or number of hydrostatic weight sensors.
- the hydrostatic weight sensor integrated into the seat base constantly monitors absolute weight of the occupant, while the combination of this sensor and the hydrostatic weight sensor located in the seat back are used to correlate loading signals. These signals are used to determine if an occupant is sitting forward or leaning back.
- the instant invention can determine an occupant's lateral weight distribution. This information can be used to measure an occupant's position profile prior to and during a frontal, side, or rear-end crash to determine if and when primary and/or secondary safety devices such as seat pre-tensioners and multi-stage air bags should be deployed.
- one object of the instant invention is to provide an improved seat weight sensor that can sense the distribution of weight of the seat loading.
- a further object of the instant invention is to provide an improved seat weight sensor that can sense the position of the occupant on the seat.
- a yet further object of the instant invention is to provide an improved seat weight sensor that can sense the stature of the occupant on the seat.
- a yet further object of the instant invention is to provide an improved seat weight sensor that provides a consistent and accurate measure of the seat loading independent of the location of the source of weight on the seat.
- a yet further object of the instant invention is to provide an improved seat weight sensor that provides a consistent and accurate measure of the seat loading independent of the size and distribution of the source of weight on the seat.
- a yet further object of the instant invention is to provide an improved seat weight sensor that provides a consistent and accurate measure of the seat loading independent of the amount of weight on the seat.
- a yet further object of the instant invention is to provide an improved seat weight sensor that operates under a wide range of ambient temperature and pressure conditions.
- a yet further object of the instant invention is to provide an improved seat weight sensor that can distinguish between a rear facing infant seat, for which an air bag system is preferably not deployed, and other occupants for which an air bag system is preferably deployed in the event of a crash of sufficient severity.
- a yet further object of the instant invention is to provide an improved seat weight sensor that can be incorporated into an intelligent safety restraint system for which the preferable mode of the activation of a controllable occupant restraint system is dependent upon the weight of the occupant.
- a yet further object of the instant invention is to provide an improved seat weight sensor that is inexpensive to produce.
- one feature of the instant invention is a fluid filled bladder formed within the seat cushion.
- Another feature of the instant invention is fluid filled bladder comprising a plurality of distinct chambers.
- Yet another feature of the instant invention is a pressure sensor operatively coupled to the fluid filled bladder for measuring the pressure therein.
- Yet another feature of the instant invention is a differential pressure sensor operatively coupled to the fluid filled bag for measuring the pressure therein relative to local atmospheric pressure.
- Yet another feature of the instant invention is the incorporation of a gas as the fluid in the fluid filled bladder.
- Yet another feature of the instant invention is the incorporation of a plurality of hydrostatic weight sensors in the seat.
- Yet another feature of the instant invention is the incorporation of a plurality of hydrostatic weight sensors in the seat base.
- Yet another feature of the instant invention is the incorporation of at least one hydrostatic weight sensor in the seat base, and at least another hydrostatic weight sensor in the seat back-
- Yet another feature of the instant invention is the incorporation of a signal processor for sensing the weight, position or stature of the occupant from the plurality of pressure measurements from the associated plurality of hydrostatic weight sensors.
- the specific features of the instant invention provide a number of associated advantages.
- One advantage of the instant invention with respect to the prior art is that the plurality of hydrostatic weight sensors within the base of the seat provides a means for determining the position of the occupant on the seat.
- Another advantage of the instant invention is that the plurality of hydrostatic weight sensors respectively in the seat base and the seat back provides a means for determining the stature and position of the occupant on the seat.
- the hydrostatic weight sensor comprising a bladder with a plurality of chambers provides a means for determining the position of the occupant on the seat.
- plurality hydrostatic weight sensors provides a measure of occupant position and stature which can be used to control the activation of a safety restraint system so improve the performance thereof.
- the instant invention provides a system and method for sensing the distribution of weight on a vehicle seat, from which the position and stature of an occupant seated thereon can be determined and used to control the activation of a safety restraint system.
- FIG. 1 illustrates the hydrostatic weight sensor system in accordance with one aspect of the instant invention.
- FIG. 2 illustrates the signals from the pressure sensors of respective hydrostatic weight sensors corresponding to seat loading configurations illustrated in Figs. 3a, 3b, and 3c, in accordance with one aspect of the instant invention.
- FIG. 3a illustrates the unloaded state corresponding to Fig. 2, in accordance with one aspect of the instant invention.
- FIG. 3b illustrates a loading transition corresponding to Fig. 2, in accordance with one aspect of the instant invention.
- FIG. 3c illustrates the static loading state corresponding to Fig. 2, in accordance with one aspect of the instant invention.
- FIG. 4 illustrates the unloaded state in accordance with a second aspect of the instant invention..
- FIG. 5 illustrates a loading configuration with the occupant leaning right in accordance with a second aspect of the instant invention.
- FIG. 5a illustrates the pressure sensor signals from the laterally proximate hydrostatic weight sensors corresponding to the loading configuration of Fig. 5, in accordance with a second aspect of the instant invention.
- FIG. 6 illustrates a loading configuration with the occupant leaning left in accordance with a second aspect of the instant invention.
- FIG. 6a illustrates the signals from the pressure sensors of the laterally proximate hydrostatic weight sensors corresponding to the loading configuration of Fig. 6, in accordance with a second aspect of the instant invention.
- FIG. 7a illustrates a first stage of loading of the hydrostatic weight sensor resulting from a rear-end collision, in accordance with a third aspect of the instant invention.
- FIG. 7b illustrates a second stage of loading of the hydrostatic weight sensor resulting from a rear-end collision, in accordance with a third aspect of the instant invention
- FIG. 7c illustrates a third stage of loading of the hydrostatic weight sensor resulting from a rear-end collision, in accordance with a third aspect of the instant invention
- FIG. 7d illustrates a fourth stage of loading of the hydrostatic weight sensor resulting from a rear-end collision, in accordance with a third aspect of the instant invention
- FIG. 7e illustrates a fifth stage of loading of the hydrostatic weight sensor resulting from a rear-end collision, in accordance with a third aspect of the instant invention
- FIG. 8 illustrates the signals from the pressure sensors of respective hydrostatic weight sensors corresponding to a seat loading event resulting from a rear-end collision corresponding to Figs. 7a, 7b, 7c, 7d and 7e, in accordance with a third aspect of the instant invention.
- FIG. 9 illustrates an environment of the instant invention, in accordance with a fourth aspect of the instant invention.
- FIG. 10 illustrates another aspect of the instant invention wherein a bladder is formed from the cushion of the seat.
- a hydrostatic weight sensor system 10 in accordance with one aspect of the instant invention comprises at least one hydrostatic weight sensor 12 positioned under a foam seat bottom cushion 14 on a vehicle seat base 16, and at least one hydrostatic weight sensor 18 positioned under a foam seat back cushion 20.
- Each hydrostatic weight sensor 12 and 18 incorporates respective pressure sensor 22 and 24 respectively connected to a signal processor 26.
- the pressure within the hydrostatic weight sensor 18 relative to atmospheric pressure gives an estimate of the occupant weight that is supported by the seat back so as to determine if an occupant 5 is leaning forward or back.
- the hydrostatic weight sensors 12 and 18 are preferably partially filled with fluid so as to accommodate changes in pressure due to altitude and temperature.
- the pressure sensors 22 and 24 generate respective voltage signals that are proportional to applied pressure and linear over the full range of expected occupant loading.
- the pressure sensor voltage outputs are fed to the signal processor 26 for calculating occupant weight, weight distribution, and position therefrom, for example by comparing the measured pressure signals with pre-stored thresholds.
- the pressure of the fluid in the respective hydrostatic weight sensors 12 and 18 sensed by the respective pressure sensors 22 and 24 increases responsive thereto.
- the outputs from the respective pressure sensors 22 and 24 are dependent upon the location and orientation of the occupant 5.
- the respective pressure transducer signals change responsive thereto.
- the signal processor 26 calculates and stores the occupant weight, position, and stature by correlating the signals from the hydrostatic weight sensor 12 located in the seat base with the hydrostatic weight sensor 18 located in the seat back..
- the signal processor 26 controls the safety restraint system, such as an air bag or a seat belt pretension ⁇ r, responsive to the occupant weight, position, and stature measurements and position time history so as to mitigate injury to the occupant 5 that might otherwise result in an uncontrolled safety restraint system if, for example, the occupant 5 were too close to a deploying air bag during a vehicle crash.
- the safety restraint system such as an air bag or a seat belt pretension ⁇ r
- a hydrostatic weight sensor system 10 in accordance with a second aspect of the instant invention comprises a plurality of hydrostatic weight sensors 34 and 36 — as either distinct sensor elements or as distinct chambers within a common bladder - - positioned longitudinally proximate one another, fore and aft respectively, under a foam seat bottom cushion 14 on a vehicle seat base 1.
- Each hydrostatic weight sensor 34 and 36 incorporates respective differential pressure sensors 35 and 37 respectively connected to a signal processor 26.
- an occupant 5 seated on the base 40 of seat 3 causes the pressure inside a hydrostatic weight sensor 34 to increase such that that product of the differential pressure, as sensed by differential pressure sensor 35, multiplied times the area of the base 34.1 of the bladder 34 is substantially equal to the component of occupant weight distributed by the seat cushion foam 44 over the top 34.2 of the bladder 34.
- the occupant 5 seated on the base 40 of seat 3 causes the pressure inside a hydrostatic weight sensor 36 to increase such that that product of the differential pressure, as sensed by differential pressure sensor 37, multiplied times the area of the base 36.1 of the bladder 36 is substantially equal to the component of occupant weight distributed by the seat cushion foam 44 over the top 36.2 of the bladder 36.
- the respective pressure signal outputs 38 and 39 from respective differential pressure sensors 35 and 37 are operatively coupled to an electronic control module 50 which converts the respective pressure signal outputs 38 and 39 to a measure of occupant weight using known analog, digital, or microprocessor circuitry and software. More particularly, the total occupant weight is calculated as the sum of the respective weight components, and the position of the occupant is calculated as the center of loading of the weight components based upon the known locations of the respective hydrostatic weight sensors 34 and 36.
- a crash sensor 60 is also operatively coupled to the signal processor 26.
- the signal processor 26 Responsive to a crash detected by the crash sensor 60, and further responsive to the sensed weight and position of the occupant 5 as transformed from the pressure signal outputs 38 and 39, the signal processor 26 generates a signal 80 which is operatively coupled to one or more initiators 90 of one or more gas generators 100 mounted in an air bag inflator module 110, thereby controlling the activation of the air bag inflator module assembly 7 so as to inflate the air bag 120 as necessary to protect the occupant 5 from injury which might otherwise be caused by the crash.
- the electrical power necessary to carry out these operations is provided by a source of power 70, preferably the vehicle battery.
- a second hydrostatic weight sensor system 28 with two laterally adjacent compartments 30 and 32 is placed on top of the first hydrostatic weight sensor 12.
- the second hydrostatic weight sensor system 28 could be implemented as distinct hydrostatic weight sensors 30 and 32.
- the side-to-side weight distribution of the occupant 5 can be determined by measuring the sign and magnitude of the relative pressure between the two laterally adjacent compartments 30 and 32.
- the hydrostatic weight sensor system 10 of the instant invention is used to determine the stature of the occupant for purposes of controlling a safety restraint system.
- Figs. 7a, 7b, 7c, 7d, and 7e illustrate the progression of occupant motion resulting from a rear-end collision
- Fig. 8 illustrates the corresponding signals from the respective hydrostatic weight sensors 12 and 18 located under the seat base and seat back respectively.
- the hydrostatic weight sensor 18 in the seat back sensor initially experiences a large loading due to the occupant's rearward reaction force backward against the .
- the combined sensor responses from hydrostatic weight sensors 12 and 18 provide a crash "signature" which is responsive to occupant weight and stature, and which is used, along with prior position and weight data, to determine if and when seat pre-tensioning or an air bag deployments (primary or secondary) are required so as to provide optimal occupant protection.
- a hydrostatic weight sensor 12 is provided by forming an associated bladder 13 from the seat bottom cushion 14, either by molding the seat bottom cushion 14 with an internal cavity that constitutes the bladder 13 or by scalloping the mating surface of top 14a and bottom 14b halves of the seat bottom cushion 14, and then bonding these halves together so that the mating scalloped portions thereby form the bladder 13.
- the hydrostatic weight sensor system 10 of the present invention provides direct, realtime data on the weight, stature and position of the occupant 5.
- the instant invention provides additional real-time information about the occupant which can be used to provide better control of the activation of safety restraint systems.
- the hydrostatic weight sensor system 10 of the instant invention is inherently insensitive to obstruction by books or newspapers and to objects placed under the seat, because the hydrostatic weight sensor system 10 is incorporated within the seat.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Aviation & Aerospace Engineering (AREA)
- Transportation (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Air Bags (AREA)
- Seats For Vehicles (AREA)
Abstract
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019980707202A KR20000064583A (ko) | 1997-01-08 | 1998-01-08 | 자동차시트중량감지시스템 |
DE69819614T DE69819614T2 (de) | 1997-01-08 | 1998-01-08 | Gewichtssensor für Kraftfahrzeugsitze |
EP98904533A EP0892728B1 (fr) | 1997-01-08 | 1998-01-08 | Système capteur de poids pour siège d'automobile |
JP53105998A JP2002513349A (ja) | 1997-01-08 | 1998-01-08 | 自動車座席重量検知システム |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US3401897P | 1997-01-08 | 1997-01-08 | |
US60/034,018 | 1997-01-08 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998030411A1 true WO1998030411A1 (fr) | 1998-07-16 |
Family
ID=21873809
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1998/000252 WO1998030411A1 (fr) | 1997-01-08 | 1998-01-08 | Systeme capteur de poids pour siege d'automobile |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO1998030411A1 (fr) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
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EP0900705A3 (fr) * | 1997-09-03 | 2000-02-02 | Delco Electronics Corporation | Dispositif d'estimation du poids de l'occupant d'un véhicule |
EP0955203A3 (fr) * | 1998-05-05 | 2001-01-31 | Delphi Technologies, Inc. | Montage d' un détecteur de charge pour sièges de véhicules |
GB2352860A (en) * | 1999-08-02 | 2001-02-07 | Autoliv Dev | A sensor system for moderating air bag deployment |
US6476514B1 (en) | 2000-03-29 | 2002-11-05 | Ford Global Technologies, Inc. | Occupant detection sensor assembly for seats |
WO2003084786A1 (fr) * | 2002-04-09 | 2003-10-16 | M.I.Laboratories Corporation | Declenchement d'un airbag de vehicule |
US7243945B2 (en) | 1992-05-05 | 2007-07-17 | Automotive Technologies International, Inc. | Weight measuring systems and methods for vehicles |
US7387183B2 (en) | 1995-06-07 | 2008-06-17 | Automotive Technologies International, Inc. | Weight measuring systems and methods for vehicles |
US7525442B1 (en) | 2002-08-26 | 2009-04-28 | Automotive Technologies International, Inc. | Method for controlling output of a classification algorithm |
US7620521B2 (en) | 1995-06-07 | 2009-11-17 | Automotive Technologies International, Inc. | Dynamic weight sensing and classification of vehicular occupants |
US7762582B2 (en) | 1995-06-07 | 2010-07-27 | Automotive Technologies International, Inc. | Vehicle component control based on occupant morphology |
US7779956B2 (en) | 1995-06-07 | 2010-08-24 | Automotive Technologies International, Inc.. | Vehicular seats with weight sensing capability |
US7900736B2 (en) | 1995-06-07 | 2011-03-08 | Automotive Technologies International, Inc. | Vehicular seats with fluid-containing weight sensing system |
US7976060B2 (en) | 1995-06-07 | 2011-07-12 | Automotive Technologies International, Inc. | Seat load or displacement measuring system for occupant restraint system control |
EP2477018A1 (fr) * | 2011-01-17 | 2012-07-18 | Erbicol SA | Dispositif destiné à recevoir le basculement de la pression interne dans un tuyau flexible rempli de liquide et son utilisation dans un organe de direction d'un véhicule |
EP3369610A1 (fr) * | 2017-03-01 | 2018-09-05 | Delphi Technologies, Inc. | Système pour déterminer la posture et le poids d'un occupant d'un siège |
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Publication number | Priority date | Publication date | Assignee | Title |
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US7243945B2 (en) | 1992-05-05 | 2007-07-17 | Automotive Technologies International, Inc. | Weight measuring systems and methods for vehicles |
US7407029B2 (en) | 1992-05-05 | 2008-08-05 | Automotive Technologies International, Inc. | Weight measuring systems and methods for vehicles |
US7620521B2 (en) | 1995-06-07 | 2009-11-17 | Automotive Technologies International, Inc. | Dynamic weight sensing and classification of vehicular occupants |
US7976060B2 (en) | 1995-06-07 | 2011-07-12 | Automotive Technologies International, Inc. | Seat load or displacement measuring system for occupant restraint system control |
US7900736B2 (en) | 1995-06-07 | 2011-03-08 | Automotive Technologies International, Inc. | Vehicular seats with fluid-containing weight sensing system |
US7779956B2 (en) | 1995-06-07 | 2010-08-24 | Automotive Technologies International, Inc.. | Vehicular seats with weight sensing capability |
US7387183B2 (en) | 1995-06-07 | 2008-06-17 | Automotive Technologies International, Inc. | Weight measuring systems and methods for vehicles |
US7762582B2 (en) | 1995-06-07 | 2010-07-27 | Automotive Technologies International, Inc. | Vehicle component control based on occupant morphology |
EP0900705A3 (fr) * | 1997-09-03 | 2000-02-02 | Delco Electronics Corporation | Dispositif d'estimation du poids de l'occupant d'un véhicule |
EP0955203A3 (fr) * | 1998-05-05 | 2001-01-31 | Delphi Technologies, Inc. | Montage d' un détecteur de charge pour sièges de véhicules |
US7766383B2 (en) | 1998-11-17 | 2010-08-03 | Automotive Technologies International, Inc. | Vehicular component adjustment system and method |
GB2352860B (en) * | 1999-08-02 | 2003-02-12 | Autoliv Dev | Improvements in or relating to a sensor system |
GB2352860A (en) * | 1999-08-02 | 2001-02-07 | Autoliv Dev | A sensor system for moderating air bag deployment |
US6476514B1 (en) | 2000-03-29 | 2002-11-05 | Ford Global Technologies, Inc. | Occupant detection sensor assembly for seats |
WO2003084786A1 (fr) * | 2002-04-09 | 2003-10-16 | M.I.Laboratories Corporation | Declenchement d'un airbag de vehicule |
US7525442B1 (en) | 2002-08-26 | 2009-04-28 | Automotive Technologies International, Inc. | Method for controlling output of a classification algorithm |
US8054193B1 (en) | 2002-08-26 | 2011-11-08 | Automotive Technologies International, Inc. | Method for controlling output of a classification algorithm |
EP2477018A1 (fr) * | 2011-01-17 | 2012-07-18 | Erbicol SA | Dispositif destiné à recevoir le basculement de la pression interne dans un tuyau flexible rempli de liquide et son utilisation dans un organe de direction d'un véhicule |
EP3369610A1 (fr) * | 2017-03-01 | 2018-09-05 | Delphi Technologies, Inc. | Système pour déterminer la posture et le poids d'un occupant d'un siège |
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