A study of dependence resonance frequencies of differential capacitive sensor on time

Abstract

The article notes that airport perimeter security is considered one of the preventive measures in aviation security and the need to stimulate innovative devices led to the need to improve the sensors uses in perimeter security-warning systems. It emphasizes that the most widely used sensor in perimeter security-warning systems is the capacitive sensor and the importance of adapting to environmental changes is shown. Therefore, the article emphasizes that the purpose is to explore the environmental dependence of the frequency changes of two auto-generators built on digital logic elements applied as differential capacitive sensors. For this purpose, it is described the results from investigations of frequency variations of two auto-generators built on digital logic elements used as differential capacitive sensors in perimeter security-warning systems, as well as their synchronous operation in relation to each other’s dependence on time. The mathematical expectation and dispersion of the variation values of the resonance frequencies of auto-generators which were connected to sensitive elements of different lengths were calculated in experiments, and it was found that the frequencies of the auto-generators changed more synchronously with each other. As a result, it is determined experimentally that, taking into account the time drift of the resonant frequency of auto-generators with sensitive elements of two meters length in laboratory conditions, the discreteness of the measured parameters allows us to determine the weight of the approaching object, and in all cases, the resonant frequencies of both auto-generators change approximately equally in both directions with a small difference depending on time.