# US 2018/0022233 A1 · Occupant detection and classification system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0022233 A1 - Document ID: US20180022233A1 - Status: Published application - Kind: A1 - Application number: 15/655,542 - Filed: 2017-07-20 - Published: 2018-01-25 - Earliest claimed: 2016-07-20 - Assignees: Joyson Safety Systems Acquisition LLC - Applicants: TK Holdings Inc. - Inventors: Phillip Bernard Maguire; Daniel Tabar; David Haggitt; Jeffrey Bennett - Web page: https://patentgrep.com/patent/US20180022233A1 ## CPC - B60R 22/48: Control systems, alarms, or interlock systems, for the correct application of the belt or harness - B60N 2/0025: {by using weight measurement} - B60N 2/0026: {for distinguishing between humans, animals or objects} - B60N 2/0032: {mounted on springs} - B60N 2/0033: {mounted on or in the foam cushion} - B60N 2/0034: {in, under or on the seat cover} - B60N 2/0035: {characterised by the sensor data transmission, e.g. wired connections or wireless transmitters therefor; characterised by the sensor data processing, e.g. seat sensor signal amplification or electric circuits for providing seat sensor information} - B60R 21/01: Electrical circuits for triggering {passive} safety arrangements, {e.g. airbags, safety belt tighteners,} in case of vehicle accidents or impending vehicle accidents {(electrical circuits for transmission of signals between steering wheel and the vehicle itself B60R16/027; for electrically actuating belt retractor locking means B60R22/343)} - B60R 21/015: 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} - G01N 27/228: {Circuits therefor (measuring capacitance per se G01R27/26)} - B60N 2210/12: Capacitive; Electric field - B60N 2210/30: Temperature sensors - B60N 2220/20: using a deterministic algorithm - B60N 2230/10: Wired data transmission - B60N 2230/30: Signal processing of sensor data - B60R 2021/0032: {Position of passenger} - B60R 2021/01211: {Expansion of air bags} - B60R 2022/4858: {for sensing pressure on seat} - B60R 2022/4866: {Displaying or indicating arrangements thereof} - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR - B60N: SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract An occupant detection system includes a controller, a sensing electrode, and a shield electrode, the electrodes disposed in a vehicle seat. The controller is electrically coupled to the sensing electrode and shield electrode by a sensing circuit. The controller is configured to send an input signal to the sensing electrode, the shield electrode, or both and measures current, impedance, or capacitance values to determine the presence of an object on the seat, to classify the object, or both. ## Claims ### Claim 1 A system for classifying an occupant in a vehicle comprising: at least one pair of occupant classification sensors, each occupant classification sensor having a sensing electrode mountable in a seat bottom of a vehicle seat and a shield electrode located in the vehicle seat opposite the sensing electrode; a respective sensing circuit operatively coupled to the respective sensing electrode and shield electrode for each occupant classification sensor in the at least one pair; a controller comprising computer memory operatively coupled to the respective sensing circuits, wherein the controller operates to configure the respective sensing circuits into a plurality of circuit configurations; and wherein in the circuit configurations the sensing electrode and the shield electrode are electrically coupled to the sensing circuit, wherein the controller sends a control signal to the sensing circuit, and measures a plurality of sensing current measurements, each sensing current measurement corresponding to one of the circuit configurations, wherein the sensing circuit is further configured to detect a change in at least one current characteristic of sensing current on at least one pair of sensing electrodes due to the presence of the object located on the vehicle seat, wherein the sensing circuits corresponding to the at least one pair of sensing electrodes provide, to the controller, a respective output signal corresponding to a respective change in the sensing current on the respective sensing electrodes, wherein the memory stores threshold data establishing occupant classifications according to threshold boundaries, and wherein the controller uses the respective output signals as a coordinate pair to identify a respective occupant classification for the coordinate pair relative to the threshold boundaries. ### Claim 2 (depends on 1) The system of claim 1, wherein the controller utilizes the threshold boundaries stored in the memory and evaluates the coordinate pair relative to the threshold boundaries to identify the respective occupant classification for the coordinate pair. ### Claim 3 (depends on 1) The system of claim 1, wherein the controller operates to configure the respective sensing circuits into four circuit configurations for each occupant classification sensor. ### Claim 4 (depends on 1) The system of claim 1, further comprising a left side occupant classification sensor and a right side occupant classification sensor, wherein the coordinate system comprises x-axis values and y-axis values, and wherein the x-axis values are Q values representing magnitudes of quadrature components of left side sensing current on a left side sensing electrode and the y-axis values represent additional magnitudes of quadrature components of right side sensing currents on a right side sensing electrode. ### Claim 5 (depends on 1) The system of claim 1 further comprising a front occupant classification sensor and a rear occupant classification sensor, wherein the coordinate system comprises x-axis values and y-axis values, and wherein the x-axis values are Q values representing magnitudes of the quadrature components of front sensing current on a front sensing electrode and the y-axis values represent additional magnitudes of quadrature components of rear sensing current on a rear sensing electrode. ### Claim 6 (depends on 1) The system of claim 1, the controller calculates impedance between the shield electrode and the corresponding sensing electrode, based on the change in current, to classify the object. ### Claim 7 (depends on 6) The system of claim 6, wherein the controller determines whether to activate a seat belt indicator or an air bag. ### Claim 8 (depends on 6) The system of claim 6, wherein a compressible material is disposed between the sensing electrode and the shield electrode. ### Claim 9 (depends on 1) The system of claim 1, further comprising additional pairs of occupant classification sensors positioned in respective zones of a vehicle seat. ### Claim 10 (depends on 1) The system of claim 1, wherein the threshold data establishes a first threshold boundary between a 6 year old child classification and a 5th percentile female classification such that the controller compares the coordinate pair of the output signals to the first threshold boundary to identify the occupant classification for the coordinate pair. ### Claim 11 (depends on 1) The system of claim 1, wherein the threshold data establishes a second threshold boundary between a 5th percentile female classification and a 50th percentile male classification such that the controller compares the coordinate pair of the output signals to the second threshold boundary to identify the occupant classification for the coordinate pair. ### Claim 12 (depends on 1) The system of claim 1, wherein at least one occupant classification sensor is positioned proximately to a pan region of a base portion of the vehicle seat, and wherein at least one other occupant classification sensor is positioned proximately to a springs region of a base portion of the vehicle seat. ### Claim 13 (depends on 1) The system of claim 1, wherein the threshold boundaries and the output signals are applied to a coordinate system as impedance values for the respective occupant classification sensors. ### Claim 14 (depends on 13) The system of claim 13, wherein the controller overlays multiple sets of coordinate pairs onto a coordinate system that establishes the threshold boundaries such that output signals for multiple pairs of occupant classification sensors are compared by the controller and assigned occupant classifications relative to the threshold data. ### Claim 15 A system for classifying objects positioned on a vehicle seat within a vehicle, the system comprising: a first occupant classification sensor secured to a front region of the vehicle seat; a second occupant classification sensor secured to a rear region of the vehicle seat; wherein each occupant classification sensor has a sensing electrode positioned oppositely a shield electrode; a respective sensing circuit operatively coupled to the respective sensing electrode and shield electrode for each occupant classification sensor; a controller comprising computer memory operatively coupled to the respective sensing circuits, wherein the controller operates to configure the respective sensing circuits into a plurality of circuit configurations; and wherein in the circuit configurations, the sensing electrode and the shield electrode are electrically coupled to the sensing circuit, wherein the controller sends a control signal to the sensing circuit and measures a plurality of sensing current measurements, each sensing current measurement corresponding to one of the circuit configurations, wherein the sensing circuit is further configured to detect a change in at least one current characteristic of sensing current on at least one pair of sensing electrodes due to the presence of the object located on the vehicle seat, wherein the sensing circuits corresponding to the at least one pair of sensing electrodes provide, to the controller, a respective output signal corresponding to a respective change in sensing current on the respective sensing electrodes, wherein the memory stores threshold data establishing occupant classifications according to threshold boundaries in a coordinate system comprising Q values of the first occupant classification sensor on an x-axis and additional Q values of the second occupant classification sensor on the y-axis, wherein Q values represent magnitudes of the quadrature components of sensing current signals on respective sensing electrodes of each occupant classification sensor and wherein the controller uses the respective output signals as a coordinate pair to place within the coordinate system and identify a respective occupant classification for the coordinate pair. ### Claim 16 (depends on 15) A system according to claim 15, wherein the front region corresponds to a pan region of a vehicle seat base. ### Claim 17 (depends on 15) A system according to claim 15, wherein the rear region corresponds to a springs region of a vehicle seat base. ### Claim 18 (depends on 15) A system according to claim 15, wherein the first occupant classification sensor is elongated in comparison to the second occupant classification sensor. ### Claim 19 (depends on 15) A system according to claim 15, wherein the sensing electrode and the shield electrode comprise copper tape plates separated by elastomeric spacers. ### Claim 20 (depends on 15) A system according to claim 15, wherein the elastomeric spacers have a hardness measurement in the range of 35 durometers to 45 durometers. ### Claim 21 (depends on 15) A system according to claim 15, wherein the sensing electrode and the shield electrode are positioned on a support structure that is so dimensioned as to fit in the vehicle seat by extending from the front region of the vehicle seat to the rear region of the vehicle seat. ### Claim 22 (depends on 15) A system according to claim 15, wherein the support structure is positioned in the vehicle seat so as to be centered laterally across the vehicle seat such that a proximate edge of the first occupant classification sensor is adjacent a rear edge of a pan region of the vehicle seat and a distal edge of the second occupant classification sensor is adjacent a back edge of a springs region of the vehicle seat. ### Claim 23 (depends on 15) A system according to claim 15, wherein the first occupant classification sensor comprises a left split sensor and a right split sensor positioned in the vehicle seat to define a space there between. ### Claim 24 (depends on 15) The system of claim 15, wherein the controller operates to configure the respective sensing circuits into four circuit configurations for each occupant classification sensor.