Abstract:
A breath analyzer system 10 and method 400 for determining an estimate of blood alcohol concentration of a person 16. A light source 24 projects light into a sampling region 16 where breath from the person 16 is expected. A first light detector 28 and a second light detector 32 are configured to detect light intensity of light having certain wavelengths at a first time T1 and a second time T2. Signals from the light detectors 28, 32 at the first time T1 and the second time T2 are used to determine an estimate of the blood alcohol concentration of the person 16 by determining a ratio of a first light detector signal change ΔVE to a second light detector signal change ΔVE.
Abstract:
Driver distraction in a motor vehicle is assessed by capacitively detecting the driver's head pose relative to the forward direction of vehicle motion. A symmetrical array of sensor electrodes (A-H) is disposed in the cockpit ceiling (22) above the driver's head (24), and pairs of electrodes (A/E, B/F, C/G, D/H) disposed along varying axes of rotation (30-36) with respect to the forward direction are successively activated for capacitance measurement. The capacitance measurements are combined to form a signal whose strength depends on the degree of alignment between the driver's head (24) (i.e., the head pose) and the respective axes of rotation (30-36), and the driver's head pose is calculated to assess driver distraction.
Abstract:
Driver distraction in a motor vehicle is assessed by capacitively detecting the driver's head pose relative to the forward direction of vehicle motion. A symmetrical array of sensor electrodes (A-H) is disposed in the cockpit ceiling (22) above the driver's head (24), and pairs of electrodes (A/E, B/F, C/G, D/H) disposed along varying axes of rotation (30-36) with respect to the forward direction are successively activated for capacitance measurement. The capacitance measurements are combined to form a signal whose strength depends on the degree of alignment between the driver's head (24) (i.e., the head pose) and the respective axes of rotation (30-36), and the driver's head pose is calculated to assess driver distraction.
Abstract:
A chemical vapor sensor (100) is provided that passively measures a suspect chemical species of interest with high sensitivity and chemical specificity, for use with safety systems. A vapor concentrator amplifies a suspect chemical vapor concentration to a detectible level, for use with an infrared detector (126). Compensation is provided for environmental variations that may influence the passive measurement of the chemical vapor sensor (100). Environmental variations may include extrinsic vapors in the surrounding air, on air currents that divert the sample vapor as it drifts from the suspect vapor source to a sampling intake (110). In an example, ethanol vapor is measured and carbon dioxide tracer measurements are used to calculate an ethanol vapor measurement that is adjusted for environmental variations. In a preferred embodiment a time artifact filter sets the output of the carbon dioxide sensor to match the time dependence of the ethanol sensor, to calculate blood alcohol concentration.
Abstract:
An apparatus and method for determining an approximation to a measure of the volatility of fuel on-board a vehicle having an internal combustion engine. The method includes the steps of measuring at least one characteristic of the fuel (14) corresponding to a temperature of the fuel, a volume of the fuel, and a concentration of oxygenates within the fuel; determining an approximation of the a measure of the volatility of the sample volume of fuel (18, 20, 22, 24, 26, 28, 30) using a linear function based on the at least one measured characteristic of the fuel corresponding to temperature, volume, and concentration of oxygenates of the fuel. Preferably, at least one temperature measurement is associated with a predetermined volume of the sample as the sample is evaluated. The method can include determining whether a fuel contains ethanol (18), and if not, whether the fuel is a winter blend of fuel (26) or a summer blend of fuel (30). The method to determine whether ethanol is present can include the steps of bringing the fuel into contact with a sensing element (18A); measuring a characteristic of the fuel corresponding to concentration of oxygenates (18B), such as the change in capacitance or resistance of the sensing element; and calculating the dielectric constant or the conductivity of the sample respectively (18C). The method to determine the type of non-ethanol containing fuel can be based on two temperature measurements taken at two predetermined volumes during the evaporation process (16, 18, 22, 24, 26, 28).
Abstract:
A chemical vapor sensor (100) is provided that measures a chemical species of interest with high sensitivity and chemical specificity. In an aspect, an ethanol vapor sensor is provided, sized for being inconspicuous and on-board a vehicle, having a passive measurement mode and an active breathalyzer mode, for detecting a motor vehicle driver that exceeds a legal limit of blood alcohol concentration (BAC), for use with vehicle safety systems. For the passive mode, a vapor concentrator is utilized to amplify a sampled vapor concentration to a detectible level for use with an infrared (IR) detector (126). In an aspect, ethanol vapor in a vehicle cabin is passively measured and if a predetermined ethanol level is measured then a countermeasure is invoked to improve safety. In an aspect, an active breathalyzer is used as a countermeasure. The active breathalyzer can be imposed for a number of vehicle trips or for a predetermined time period.
Abstract:
A chemical vapor sensor (100) is provided that passively measures a chemical species of interest with high sensitivity and chemical specificity. In an aspect, ethanol vapor in a vehicle cabin is measured, and sufficient sensitivity is provided to passively detect a motor vehicle driver that exceeds a legal limit of blood alcohol concentration (BAC), for use with vehicle safety systems. The sensor (100) can be situated in an inconspicuous vehicle cabin location and operate independently without requiring active involvement by a driver. A vapor concentrator is utilized to amplify a sampled vapor concentration to a detectible level for use with an infrared (IR) detector. In an aspect, in comparison to conventional chemical sensors, the sensitivity of detection of ethanol vapor is increased by a factor of about 1,000. Further, a single channel of infrared detection is utilized avoiding spurious infrared absorption and making the chemical vapor sensor (100) less costly to implement.
Abstract:
A transparent overlay input device (300/400) includes a transparent non-conductive substrate (306/406), a plurality of transparent conductive electrode pairs (308A, 308B/408A, 408B) and a transparent non-conductive cover (310/410A). The plurality of transparent conductive electrode pairs (308A, 308B/408A, 408B) are formed on the substrate (306/406) and each form a proximity sensitive region and include a first electrode that receives an input signal and a second electrode that provides an output signal. The first and second electrodes are capacitively coupled and the capacitance of the electrode pair changes when a conductive member, e.g., a user's finger, is located near the electrode pair (308A, 308B/408A, 408B). The transparent non-conductive cover (310/410A) is formed on the substrate (306/406) over the electrode pairs (308A, 308B/408A, 408B).
Abstract:
An ethanol sensing unit (10) and a method of using, wherein the unit (10) is particularly suitable for use in a confined environment (16) such as the passenger compartment (16) of a passenger vehicle (18). The sensing unit (10) comprises a device (12,20) for collecting ethanol vapors while the device (12,20) is at a first temperature, a device (12,24) for heating the collecting device (12,20) to a second temperature higher than the first temperature so as to release ethanol vapors from the collecting device (12,20), and a device (26,28) for sensing the ethanol vapors released from the collecting device (12,20) when heated by the heating device (24). The sensing unit (10) is also adapted to delay the operation of the heating device (24) until a period of time sufficient for the collecting device (12,20) to adsorb ethanol vapors from air contained in the confined environment (16).