Channel consistency calibration of planar eddy-current sensor arrays

Speaker:
Liu, Lihui; National University of Defense Technology; China

Authors:
Chen, C.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China
Liu, L.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China
Pan, M.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China
Ren, Y.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China
Tian, W.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China
Wang, W.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China
Yu, Y.; College of Mechatronics Engineering and Automation, National University of Defense Technology; China

ID: ECNDT-0449-2018
Session: Eddy Current-Techniques 2
Room: H2
Date: 2018-06-14
Time: 14:30 - 14:50

Planar eddy-current sensor arrays have several advantages such as good coherence, fast response speed and high sensitivity, which can be used for defect inspection of crucial parts in mechanical equipments, and a key point to improve the detection performance is to ensure the channelconsistency of the planar eddy-current sensor arrays. The principle and characteristics of planar eddy-current sensor arrays are introduced in this paper, andthe channel consistency calibration algorithm is investigated based on least squares principle. An experimental system was established based on a field programmable gate array (FPGA) and ARM processor, which was utilized to inspect the defects in aluminum alloy. Based on this system, the channel data before and after calibration are analyzed, and the detection effect of three artificial defects is compared when the sensor channel calibration is implemented or not. The experimental results show that the sensor has excellent channel consistency and repeatability after calibration. The detection results of the three defects with size of 5 mm (length) x 0.1 mm(width) x 1 mm (depth), 7 mm (length) x 0.1 mm (width) x 1 mm (depth), 9 mm (length) x 0.1 mm (width) x 1 mm (depth) respectively show that the calibration algorithm has greatly improved the performance of the system.