Inductive sensor

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

Semiconductor pressure sensor based on FET structure

Abstract: As a next step in capacitive pressure sensor development, a new sensor structure based on field effect transistor has been proposed. The sensor build up on active FET structure, has a big advantage in reference to the semiconductor capacitive sensors. Its voltage output signal (or current signal) can be simply measured in contrary to relatively difficult measurements of capacitance. An other sensor advantage is because of one side wafer processing during sensors fabrication. The sensor construction as well as details of sensor fabrication technology are described. The results of computer simulation of the sensor are discussed. High sensor pressure sensitivity and relatively low sensor dependence on temperature are very important measurement features of the PS-FET sensors. >

Temperature-compensated object sensing device and method therefor

Abstract: A device and method is provided for sensing an object or vehicle in proximity to a sensing zone, wherein the device is exposed to an environment temperature. The object sensing device comprises a sensor, such as an inductive loop having a characteristic, such as the inductance of the inductive loop, responsive to the proximity of the object is to the sensor; a signal generator, such as an oscillator, coupled to the sensor for producing a first periodical signal cycling at a first frequency dependent on the sensor characteristic and the environment temperature. A de-coupling mechanism for de-coupling or isolating the sensor from the signal generator so that the signal generator produces a second periodical signal cycling at a second frequency dependent on the environment temperature, but not substantially dependent on the characteristic of the sensor; and a device for producing a temperature-compensated response indicative of whether the object is in the sensing zone from the first and second periodical signals or their respective frequencies. Using the temperature-compensated object or vehicle sensing device, a gate operating system and a vehicle driver stimulus device is also provided herein.

Partial discharge measurement in transmission-class cable terminations

Abstract: This paper describes on-line and off-line partial discharge (PD) measuring techniques applicable to transmission cable terminations. The on-line technique can be utilized for both extruded and pipe-type cable terminations. In pipe-type cable terminations, the on-line technique is only applicable to newly installed terminations, as it requires an internal inductive sensor. In the case of extruded cable terminations, on-line testing is made possible by using an external inductive coupler around the ground connection at the base of termination. Off-line PD measurements utilize high-frequency capacitive couplers. The coupler is attached to the overhead line within 4-feet from the termination under test. The off-line testing is applicable to new and existing cable terminations.

Large-sized precision bearing radial play multifunctional automatic measurement method and measuring apparatus

Abstract: A multifunctional automatic measurement method for radial clearance of large-scaled precision bearing adopts static measurement, dynamic measurement and three-point measurement and is capable of automatically loading and automatically measuring. The three measurement manners can be implemented on one measuring apparatus at the same time. The measuring apparatus mainly comprises an electrical system (1), a measurement pedestal (2), a sensor support (3), a sensor adjusting nut (4), an inductive sensor (5), an upper cylinder support (6), an upper loading cylinder (7), a measurement shaft centre (9), a measurement main shaft (10), a lower loading cylinder (11), a lower cylinder support (12), a measurement support (13), a synchronous motor (14), a Hall element (15), a belt wheel and cog belt (16), a precise pressure regulating valve (17), and a precise pressure gauge (18). The measuring apparatus can provide reliable detection and analysis data for high-precise measurement of radial clearance of large-scaled precision bearings (8).

Non-Destructive Testing of the Longest Span Soil-Steel Bridge in Europe—Field Measurements and FEM Calculations

Abstract: The article describes interdisciplinary and comprehensive non-destructive diagnostic tests of final bridge inspection and acceptance proposed for a soil-steel bridge made of corrugated sheets, being the European span length record holder (25.74 m). As an effect of an original concept a detailed and precise information about the structure short-term response was collected. Periodic diagnostics of bridge deformations was done one year after it was built. Load test design was based on numerical simulations performed by means of finite element method (FEM). In situ measurements were done with the aid of: inductive sensors, optical total station, and terrestrial laser scanner. The results produced by terrestrial laser scanning were used to build a precise image of structure deformation in 3D space during the tests. The accuracy of laser mapping was significantly increased using the information coming from total station and inductive sensors. These have higher accuracy and therefore can be used as reference. Thus, new quality in measurements is introduced. Good correspondence between in situ values and FEM estimations was achieved. Therefore, such a combination of testing methods can be used in non-destructive diagnostics of structures and is an interesting alternative for the standard approach, in which the measurements are done in limited number of points.