Paper Info
Title
A Displacement Sensing Method Based on Permanent Magnet and Magnetic Flux Measurement
Abstract
This paper proposes a displacement sensing method based on magnetic flux measurement. A bridge-structured magnetic circuit, formed by permanent magnets and two ferromagnetic cores, is designed and discussed. The analyses of the equivalent magnetic circuit and three-dimensional finite element simulations showed that the magnetic flux density changes linearly with the reciprocal of the sum of a constant and the displacement. A prototype sensor of the bridge structure is developed that consists of four permanent magnets as excitation, a Hall sensor as reception, and two ferromagnetic cores as the connection. Experiments have validated the feasibility of this method. The measured results show a good linearity between the sensor's output and the reciprocal of the sum of a constant and the displacement, with a correlation coefficient greater than 0.9995 across different measurement ranges. Additionally, the measured results significantly indicate that the proposed sensor is compatible with different ferromagnetic materials with a worst-case error of less than 5%. The proposed sensor has the advantages of low cost and good linearity; however, the test object is limited to ferromagnetic materials.
Year
DOI
Venue
2022
10.3390/s22124326
SENSORS
Keywords
DocType
Volume
displacement sensor, magnetic flux, permanent magnet
Journal
22
Issue
ISSN
Citations 
12
1424-8220
0
PageRank 
References 
Authors
0.34
0
7
Name
Order
Citations
PageRank
Jikai Zhang100.34
Yicheng Shi200.34
Yuewen Huang300.34
Cheng Liang400.34
Yantong Dong500.34
Yihua Kang643.66
Bo Feng701.69