In control theory and various areas of applied mathematics, it is important to approximate sets of complex geometry by unions of simple unified bodies. One of the most common methods here is covering sets with balls. In the classical statement, all the balls are equal; nevertheless, a more general statement is also of interest when the balls can be different. In this paper, we study the problem of constructing a covering of a compact set M in three-dimensional Euclidean space by a set of a given number of balls whose radii are equal to the product of a common parameter r and an individual positive coefficient. The optimality criterion is the minimum of r. We propose heuristic algorithms for constructing such coverings based on splitting the set M into zones of influence of points and finding their Chebyshev centers. Statements about the properties of these algorithms are proved, and the algorithms are implemented. The problems of covering a cube with different sets of balls of two types are solved numerically. Possible directions of further research are outlined and discussed.
Keywords: optimization, ball covering, heuristic algorithm, Chebyshev center, computational experiment
Received January 11, 2021
Revised February 20, 2021
Accepted February 25, 2021
Funding Agency: P.D.Lebedev’s research is supported by the Russian Science Foundation (project no. 19-11-00105).
Alexander Leonidovich Kazakov. Dr. Phys.-Math. Sci., Matrosov Institute for System Dynamics and Control Theory, Siberian Branch of the Russian Academy of Sciences, Irkutsk, 664033 Russia; Institute of Engineering Science of the Ural Branch of the Russian Academy of Sciences, Ekaterinburg 620049 Russia, e-mail: kazakov@icc.ru
Pavel Dmitrievich Lebedev, Cand. Phys.-Math. Sci., Krasovskii Institute of Mathematics and Mechanics of the Ural Branch of the Russian Academy of Sciences, Yekaterinburg, 620108 Russia, e-mail: pleb@yandex.ru
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Cite this article as: P.D. Lebedev, A.L. Kazakov. Iterative algorithms for constructing the thinnest coverings of polyhedra by sets of different balls, Trudy Instituta Matematiki i Mekhaniki UrO RAN, 2021, vol. 27, no. 1, pp. 116–129.