Object detection method and device based on constant electromagnetic source motor variable frequency induction field

Abstract

The invention discloses an object detection method and device based on a constant electromagnetic source motor variable frequency induction field. The object detection device comprises a front end detection device body and a background processor. According to the front end detection device body, permanent magnets are combined with a coil conducted with direct currents to generate a constant electromagnetic source. The constant electromagnetic source is placed in a magnetic shielding case. A plurality of holes are formed in one end of the magnetic shielding case, through the control over the relative movement of the holes of the magnetic shielding case and the constant electromagnetic source, the magnetic field intensity and the electric field exposed out of the magnetic shielding case from the holes change alternatively, therefore an alternating induction field is formed on the surface of a detected object, and finally, a wave source of ultrasonic waves is generated. A plurality of magnetic induction elements are fixed onto the permanent magnets to form a magnetic receiving array used for inducting magnetic fields created by reflected waves of the ultrasonic waves and sending to the background processor to be analyzed and processed. By means of the object detection method and device based on the constant electromagnetic source motor variable frequency induction field, the detection precision can be improved, broadband and large-power detection signals are flexibly generated, the detected object is not limited to metal, and the object detection method and device are suitable for wider detection scenes.

Description

technical field [0001] The invention relates to the field of electromagnetic ultrasonic detection, in particular to an object detection method and device based on a constant electromagnetic source motorized variable frequency induction field. Background technique [0002] Ultrasonic testing is one of the most commonly used non-destructive testing methods in industry. This method emits ultrasonic waves to interact with the measured object, and obtains a certain acoustic parameter distribution function of the detection target by studying reflected, transmitted and scattered waves, so as to evaluate the material, thickness, location and size of internal defects of the detection target. [0003] The traditional ultrasonic testing adopts the piezoelectric type, that is, the voltage is applied to the piezoelectric ceramic or quartz wafer probe. The ultrasonic pulse sent by the probe enters the measured object through the acoustic coupling medium, and is reflected after encounterin...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art, such as low energy conversion efficiency and low signal-to-noise ratio of received signals, and provide an object detection device based on a constant electromagnetic source motorized variable frequency induction field

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