Abstract: An improved vehicle restraint system includes a seat belt tension sensor and an occupant detection control module for characterizing the occupant of a vehicle seat to determine whether to allow or suppress deployment of supplemental inflatable restraints for the occupant. The belt tension sensor includes on-board signal processing circuitry and is coupled to occupant detection control module via a two wire interface that both powers the sensor and its signal processing circuitry and supports communication of belt tension data to the occupant detection control module. The sensor produces an electrical signal responsive to seat belt tension, and the processing circuitry generates one of a specified number of messages pertaining to the range of the measured tension, and then modulates the current through the two wire interface to communicate the generated message to the occupant detection control module.

Abstract: An improved weight-based occupant characterization method reliably distinguishes between a minimum weight adult and a child seated on a booster seat. An early characterization of the seat occupant is made in an interval following a transition event such as a door opening or ignition state change that activates the occupant detection system. During this interval, an initial characterization routine monitors the seat belt tension and the raw seat pressure to identify signal values characteristic of a minimum weight adult or a child seated on a booster seat. If the indicated occupant weight during subsequent operation of the vehicle is inconsistent with the initial characterization, the initial characterization is discarded, and the seat occupancy is characterized based on the indicated occupant weight.

Abstract: An improved vehicle restraint system includes a seat belt tension sensor and an occupant detection control module for characterizing the occupant of a vehicle seat to determine whether to allow or suppress deployment of supplemental inflatable restraints for the occupant. The belt tension sensor includes on-board signal processing circuitry and is coupled to occupant detection control module via a two wire interface that both powers the sensor and its signal processing circuitry and supports communication of belt tension data to the occupant detection control module. The sensor produces an electrical signal responsive to seat belt tension, and the processing circuitry generates one of a specified number of messages pertaining to the range of the measured tension, and then modulates the current through the two wire interface to communicate the generated message to the occupant detection control module.

Abstract: An improved vehicle seat occupant weight estimation method detects weight applied to both the seat cushion and the floor forward of the seat, and increases the measured seat weight of the occupant to account for occupant weight off-loaded to the floor. Fluid-filled bladders or other sensors are arranged to detect occupant seat weight and the weight applied to the vehicle floor forward of the seat. Upon opening of a vehicle door or an off-to-on transition of the vehicle ignition switch, the seat and floor weight sensors are monitored to detect the presence of an occupant. When the seat becomes occupied, or whenever there is a large change in the measured seat weight, the seat and floor weight are recorded, the occupant weight is estimated according to the recorded seat weight, and the inflatable restraints are allowed or suppressed based on the estimated occupant weight.

Abstract: An improved occupant detection system and method includes a fluid-filled polymeric seat cushion bladder defining multiple fluid-filled chambers corresponding to different areas of the seat cushion, with no fluid flow between such chambers. Fluid pressures in the various individual chambers are detected and processed to develop a weight estimation that is compensated for occupant position. The chambers are configured to detect occupant weight in at least forward, rearward, inboard and outboard regions of the bottom seat cushion. When the detected pressures are unevenly distributed and the pressure in the forward, rearward, inboard or outboard regions of the seat exceeds the average pressure by at least a predetermined amount, a composite pressure indicative of occupant weight is adjusted in a direction to bias the suppression status in favor of allowing restraint deployment, unless the occupant is forwardly positioned on a seat that is also forwardly positioned.

Abstract: An improved occupant detection system and method includes a fluid-filled polymeric seat cushion bladder defining multiple fluid-filled chambers corresponding to different areas of the seat cushion, with no fluid flow between such chambers. Fluid pressures in the various individual chambers are detected and processed to develop a weight estimation that is compensated for occupant position. The chambers are configured to detect occupant weight in at least forward, rearward, inboard and outboard regions of the bottom seat cushion. When the detected pressures are unevenly distributed and the pressure in the forward, rearward, inboard or outboard regions of the seat exceeds the average pressure by at least a predetermined amount, a composite pressure indicative of occupant weight is adjusted in a direction to bias the suppression status in favor of allowing restraint deployment, unless the occupant is forwardly positioned on a seat that is also forwardly positioned.

Abstract: An improved weight-based occupant characterization method reliably distinguishes between a child or small adult and a tightly cinched child seat based on a variance in the sensed occupant weight and a variance in the vehicle acceleration. The weight variance and acceleration variance are used to determine a relative or normalized variance that compensates for the effects of operating the vehicle on a rough road surface. The occupant is characterized as a child seat if the normalized variance is below a first threshold for a predetermined interval, and as a child or small adult if the normalized variation exceeds a second threshold for a predetermined interval.

Abstract: An improved occupant weight detection system measures the pressure in a fluid-filled bladder disposed in or under a foam seat cushion as an indication of occupant weight, and periodically adjusts the pressure vs. occupant weight relationship to compensate for changes due to aging and usage of the foam seat cushion. The system controller develops an aging adjustment value based on a measure of the cumulative aging and usage of the seat, and uses the developed adjustment value to compensate the operation of the system. The aging adjustment value is determined primarily as a function of occupant weight and time of seat occupancy, and the compensation is achieved by using the aging adjustment value to adjust either the estimated weight, or a threshold to which the measured pressure is compared for purposes of deciding if restraint deployment should be enabled.

Abstract: An improved occupant weight detection system measures the pressure in a fluid-filled bladder disposed in or under a foam seat cushion as an indication of occupant weight, and periodically adjusts the pressure vs. occupant weight relationship to compensate for changes due to aging and usage of the foam seat cushion. The system controller develops an aging adjustment value based on a measure of the cumulative aging and usage of the seat, and uses the developed adjustment value to compensate the operation of the system. The aging adjustment value is determined primarily as a function of occupant weight and time of seat occupancy, and the compensation is achieved by using the aging adjustment value to adjust either the estimated weight, or a threshold to which the measured pressure is compared for purposes of deciding if restraint deployment should be enabled.

Abstract: An improved weight-based occupant characterization method reliably distinguishes between an empty seat and a seat occupied by an ultralight child seat. The seat occupancy is initially characterized using a primary classification technique in which the measured seat pressure is compared to an allow threshold representative of a minimum weight adult. If the primary classification technique determines that the seat is empty and a seat belt for the passenger seat is buckled, a secondary classification technique is initiated to compare the measured seat pressure to a predetermined pressure range characteristic of occupied ultralight child seats. If the measured pressure falls within the ultralight child seat range, characterization of the primary classification technique is discarded in favor of the characterization of the secondary classification technique.

Abstract: An improved weight-based occupant characterization method distinguishes between an empty seat and a seat having a small object on it using primary and secondary classification techniques. The primary classification technique is initiated prior to vehicle movement, and characterizes the seat occupant based on measured seat pressure. If deployment of the restraint is suppressed due to the characterization of the primary classification technique, the seat occupancy is characterized by a secondary classification technique based on variation of the measured pressure once the vehicle is in motion. Once the secondary classification technique has characterized the seat occupancy, the characterization of the primary classification technique is discarded in favor of the characterization of the secondary classification technique.

Abstract: An improved weight-based occupant characterization method that can inexpensively and reliably distinguish between a child or small adult and a tightly cinched child seat. When the sensed weight is in a specified range that could be produced by a tightly cinched child seat, the system characterizes the occupant based on a detected variation in sensed weight during movement of the vehicle. If the variance of the sensed weight is below a threshold for a predetermined interval, the occupant is characterized as a child seat, since a tightly cinched seat belt severely restricts variance. If the variance exceeds the threshold for a predetermined interval, the occupant is characterized as a child or small adult. A correlative factor that can be used in distinguishing between a child seat and a child or small adult is determined by computing a slope reversal rate, or frequency, of the measured weight.

Abstract: A side impact sensor processes side acceleration signals and upon a crash event develops a deploy signal which comprises accurately timed pulses of preset duration including a single pulse wake up message and a multiple pulse deploy message. A single wire interface couples the deploy signal to a microprocessor in a central controller which manages deployment of side and frontal air bags and runs frontal impact algorithm. The pulse edges cause interrupts used to measure the pulse widths which are compared to stored values to verify the messages. A wake up pulse causes the microprocessor to give priority to an algorithm for processing the deploy message over the frontal algorithm and still service the frontal algorithm without degradation. Signal drivers in the side impact sensor impose sharp pulse edges for the deploy signal and sloping edges for other signals monitoring the state of health of the side sensor to reduce radiated emissions.

Abstract: A system and a method are provided wherein an air bag deployment command is issued if a crash event exceeds both an energy boundary curve and an oscillation boundary curve, and, furthermore, following detection of an onset of the crash event, filtered acceleration data exceeds an acceleration threshold. The threshold is preferably two-tiered to help discriminate between deployment and non-deployment events.

Abstract: A microporous sheet comprising a polymeric matrix having a liquid insoluble, particulate, activated polysaccharide media dispersed therein; use of the sheet in affinity chromatography or ion-exchange chromatography or as a biochemical reactor or battery separator; processes for manufacturing the sheet; apparatus containing the microporous sheet as its active element; and methods for using such sheet.

Abstract: A power shutdown sequence provides for an orderly power shutdown for master and slave processors sharing a single power supply while at the same time allowing the master and slave processors to retain all the information learned regardless of failures. If the master senses a shutdown condition, it sends the slaves a power down signal confirming its intention to power down the system and commanding the slaves to initiate shutdown procedures, including the storing of variables to memory. In addition, the master also initiates shutdown procedures, and after a minimum time determined sufficient to allow the slave to complete their shutdown procedures, the master powers down the system. The slaves may also initiate their own powerdown procedures if a failure in the communications link with the master is sensed.

Abstract: A drill pipe protector for use on drill pipe and the like having an outer pliant and resilient collar that envelops an insert of composite construction.

Abstract: Waste digester liquor, containing dissolved triazines, ammonium salts and iron, is treated with a mineral base until the pH is about 2.5 to 4 whereby triazines are precipitated while most of the iron remains dissolved. The triazines are separated and recycled back to the digester. The pH of the filtrate is increased to about 11 and the ammonia stripped off and recovered leaving an essentially nitrogen free aqueous solution. This can be sewered directly or concentrated to recover the salts.

Abstract: Waste digester liquor, containing dissolved triazines and iron, is treated with ammonia until the pH is about 2.5 to 4 thereby precipitating most of the triazines while leaving most of the iron in solution. The triazines are separated and recycled back to the digester. The filtrate of ammonium salts is useful as a source of fertilizer nitrogen.