PROBABILITY ESTIMATION DEGREE OF DANGER VESSELS RAPPROCHEMENT
Authors:   National university ", Burmaka I. A. ,   Odessa maritime academy",   / Национальный университет ",   Одесская морская академия", Yanchetskyy A.V. 
Published: December 2020

In the article is specified, that a decision-making process contains the following stages: control of environment, including relative position and parameters of relative motion, the exposure of situation of rapprochement of vessels, in the case of rapprochement of vessels it is necessary to produce estimation of degree of his danger, at dangerous rapprochement is needed to define the type of co-operation, depending on the degree of danger of situation of rapprochement the choice of strategy of divergence is produced. On the first stage of process of decision-making surrounding mobile objects come to light by ARPA or AIS, for which is measured parameters of motion and relative position. It is shown that on the second stage of process of decision-making, using the measured parameters, it is necessary to expect the value of speed of change of distance between vessels, taking into account that at its negative value ships are drawn together. On the third stage of process of decision-making at rapprochement of vessels estimation of degree of his danger is produced, what development of situation of rapprochement to the moment of time of their shortest rapprochement is forecast for. On the fourth stage of decision-making it is necessary to define the type of cooperation of the drawn together vessels, taking into account principle their process control of divergence. It is especially substantial for principle of locally-independent management by the process of divergence, when coordination of co-operation of vessels at dangerous rapprochement is needed. The fifth stage of decision-making is characterized by the choice of strategy of divergence, thus at the locally-independent process control of divergence the choice of strategy of divergence is produced depending on the degree of danger of situation of rapprochement, by the standard maneuver of divergence or for excessive rapprochement of vessels it is necessary to use the maneuver of urgent divergence. In work as the index of efficiency of the analytical collision avoidance systems vessels probability of safe completion of process of divergence, which is work of probabilities of successful end of stages of process of decision-making on the choice of strategy of divergence, is offered. It is shown that first three stages of decision-making on the choice of strategy of divergence are characterized by general probability of absence of danger of collision on condition that distance of the shortest rapprochement is equal to the set minimum-possible distance of rapprochement. For determination of the mentioned probability the error of distance of the shortest rapprochement is considered and expression is got for the closeness of its distributing. To that end collected dependence of error of distance of the shortest rapprochement from the errors of measuring of distance and bearing. By the got expression for the closeness of distributing of error of distance of the shortest rapprochement probability is certain of that at equality of distance of the shortest rapprochement with limit-possible distance of rapprochement there will not be the collision.