Metrological analysis of a device rof nondestructive control of flight vehicle fuel tank current conductive coatings

The article discusses and theoretically justifies a method and a device for non-destructive testing of conductive coatings of aircraft fuel tanks. The authors present a patented solution and display the essence of the measuring procedure that consists in scanning the surface by an electrode forming a capacitor with the test material. A mathematical model describes the process of detecting a closed defect with different sizes of the scanning electrode. The article contains metrological analysis of the developed device, considering the basic and additional errors that affect the results of the measurement procedure. By basic errors, in this paper, we mean the error in determining the coordinate of the defect and the systematic additive (methodological) error; by additional errors we understand thermal and dynamic ones. Among all types of errors that arise in the process of flaw detection, the most significant ones are identified. Also, methods for compensating various types of errors by constructive or algorithmic methods are proposed. Numerical analysis of the errors considered in the article is carried out. The analysis proves the possibility of defect localization with an error ≤ 6.5 mm. A summary table of the main types of errors is compiled.