Fuzzy approximator for determining the value of the current density in the electron beam of foreline plasma source

Authors: Sarin K. S., Medovnik A. V., Hodashinskiy I. A.

Annotation: This paper presents a fuzzy system for approximation the value of the current density in the electron beam of foreline plasma source. Because of insufficient knowledge about the behavior of the arc cathode spot in the operating pressure range of foreline plasma electron sources, it is difficult to construct accurate analytical models describing this behavior. Thus, we propose to construct such a model based on experimental data. As the mathematical model, we use a fuzzy system of Takagi-Sugeno type. For structure identification of this system, we propose the method of piecewise linear initialization. For parameter identification of the system, we use the recursive least-square method and the cuckoo search optimization algorithm. Validity of the model is evaluated in terms of the mean square error, which is shown not to exceed the tolerable level .

Keywords: fuzzy system, identification, cuckoo search algorithm, recursive least squares method, electron beam, current density