Inductive sensor

About: Inductive sensor is a research topic. Over the lifetime, 2282 publications have been published within this topic receiving 21984 citations.

Non-Contact Radiofrequency Inductive Sensor for the Dielectric Characterization of Burn Depth in Organic Tissues

Abstract: A flat circular transmission line-based 300 MHz resonator was implemented for the non-contact assessment of burn depths in biological tissues. Used as a transmit-and-receive sensor, it was placed at a 2 mm distance from organic material test samples (pork fillet samples) which were previously burned on their surface in various heating conditions involving different temperatures, durations, and procedures. Data extracted from the sensor by means of a distant monitoring coil were found to clearly correlate with the depth of burn observed in the tissue samples (up to 40% sensor output changes for a 7 mm burn depth) and with the heating conditions (around 5% sensor output changes observed in samples burned with identical heating procedures but at two different temperatures—75 °C and 150 °C—and around 40% sensor output changes observed between samples heated at the same temperature but with different heating procedures). These results open the way for the development of easy-to-implement assessment and monitoring techniques for burns, e.g., integrated in wearable medical dressing-like monitoring devices.

Inductive coin validation system and payphone using such system

Abstract: A coin validation arrangement, usable for example in pay telephones, uses one or more inductive sensors having a small effective magnetic field so that the inductive sensor responds only to the material of a strip across the coin. Preferably a plurality of inductive sensors are used, mounted at different heights above the floor of a coin guide, at different positions along the coin path. At each position along the coin path there may be either one or a plurality of inductive sensors. Preferably the inductive sensors are surface mount inductors on a printed circuit board which forms part of one wall of the coin guide. Such arrangements are particularly useful for recognizing coins having an outer ring made of a different material from the central disc, and for distinguishing such coins from uniform composition coins.

Lithographic projection apparatus with system for positioning a reflector

Abstract: In a lithographic projection apparatus the positions and/or orientations of reflective optical elements is dynamically controlled. The position of a reflective optical element such as a mirror (10) in an illumination or projection system is first measured using an absolute position sensor (41,42) mounted on a reference frame (RF) and thereafter measured by a relative position sensor (43,44) also mounted on said reference frame. The position of the element is controlled in accordance with the measured position, e.g. to maintain it stationary in spite of vibrations that might otherwise disturb it. The absolute sensor may be a capacitive or inductive sensor and the relative sensor may be an interferometer.

Wireless powering of sensors embedded in concrete

Abstract: Two kinds of electrical models for concrete have been used to calculate the transmission loss, propagation loss and total loss of normal incidence and oblique incidence of wave. The value of these losses depends on the electrical properties of the concrete, frequency of wave and the incidence angle. When the wave is normal incident and the frequency is between 20–80 MHz, the sensor will receive significantly larger power than the other cases we examined. Also, an optimum frequency range (corresponding to minimum transmission losses) has been identified for the cases we have examined. Detailed comparison between powering techniques that use RF signals versus low frequency inductive coupling will be presented at the conference. Also, the effects of rebars will be considered.