Abstract:
In one embodiment, a sensor assembly has a sensor housing forming a fluid chamber (28) having a surface (21) defining a normal axis. A magnetostrictive (MS) core (18, 38) that defines a central longitudinal axis is subjected to stress induced by pressurized fluid in the chamber. An excitation coil (22, 40) is coupled to the core (18, 38) to induce a magnetic flux therein. The central longitudinal axis of the core (18, 38) is coaxial with the axis normal to the fluid chamber surface (21).
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:
In one embodiment, a sensor assembly has a sensor housing (17, 38) forming a fluid chamber and a magnetostrictive wire (18, 23, 30) that undergoes stress induced by fluid in the chamber. The wire (18, 23, 30) defines opposed ends, each being associated with a respective terminal. Respective hermetic seals (20) penetrate the housing (17, 38) and are coupled to the respective terminals.
Abstract:
In one embodiment, a sensor assembly has a sensor housing (17, 38) forming a fluid chamber and a magnetostrictive wire (18, 23, 30) that undergoes stress induced by fluid in the chamber. The wire (18, 23, 30) defines opposed ends, each being associated with a respective terminal. Respective hermetic seals (20) penetrate the housing (17, 38) and are coupled to the respective terminals.
Abstract:
In one embodiment, a sensor assembly has a sensor housing forming a fluid chamber (28) having a surface (21) defining a normal axis. A magnetostrictive (MS) core (18, 38) that defines a central longitudinal axis is subjected to stress induced by pressurized fluid in the chamber. An excitation coil (22, 40) is coupled to the core (18, 38) to induce a magnetic flux therein. The central longitudinal axis of the core (18, 38) is coaxial with the axis normal to the fluid chamber surface (21).
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:
Respiration and heart rate are monitored using a fluid-filled bladder (12), where the bladder pressure is measured (16) and processed to identify minute pressure variations corresponding to the respiration and heart rate of a subject that is directly or indirectly exerting a load on the bladder (12). The respiration rate is identified by band-pass filtering the measured pressure to isolate or extract a pressure component in range of 0.15-0.5Hz (36), and the heart rate is identified by band-pass filtering the measured pressure to isolate or extract a pressure component in the range of 2-7 Hz (24). The extracted pressure components are preferably converted to a digital format and tabulated for comparison with specified thresholds to identify abnormalities and/or anomalies (30).