RADIOELECTRONIC AND COMPUTER SYSTEMS

Over the past years, unmanned aerial vehicles have been used to solve the problems of pre-and post-accident monitoring of nuclear power plants and other potentially dangerous objects. The use of a fleet (fleet grouping) of the unmanned aerial vehicle (UAV) for monitoring missions is due to the special conditions of the aggressive environment, which causes the failures of certain UAVs, and therefore needs to ensure a high level of reliability of such a fleet (the group of fleets). The most effective way to solve this problem is to use k-out-of-n redundancy. The subject of the study is a UAV fleet group with k-out-of-n redundancy. In order to take into account the reliability of the control station for various variants of the organization of UAV fleet groups, it is advisable to formulate the following tasks: to analyze the different structures of UAV fleet groups taking into account the scheme of activation of redundant UAVs; to develop and investigate models of reliability of UAV fleet groups with a centralized, decentralized and partially decentralized schemes of activation of redundant UAVs with the possibility of control station redundancy; to formulate recommendations for choosing a scheme for activation of redundant UAVs. Research results: the structure of the UAV fleet group with two-level k-out-of-n redundancy (at fleet levels and their groups using the reserve fleet) and different variants of organization of control stations were proposed. The centralized, decentralized and partially decentralized structures of activation of the redundant UAVs for a fleet group with reserve (reserve fleets) are investigated, namely: the reliability block diagrams of these systems are constructed; analytical expressions for calculating the probability of failure-free operation of the UAV fleet group based on each of these schemes are obtained; the following dependencies are obtained and investigated: probability of failure-free operation of a  UAV fleet group with different probabilities of UAV failure-free operation from the number of the main fleets in case of use of reserve fleet with three UAVs; the probability of UAV fleet group failure-free operation with different schemes of activation of redundant UAVs from the number of main fleets in the case of using a reserve fleet with three UAVs. The development and research of reliability models have made it possible to formulate tasks regarding the choice of schemes for activation of redundant UAVs and the corresponding recommendations for the organization of groups. Further research is appropriate to focus on developing software to support decision-making on choosing the options for structures and taking into account possible schemes to get areas of responsibility by UAVs.

unmanned aerial vehicle; group of fleets; reserve fleet; reliability; k-out-of-n redundancy; control station; schemes for activation of redundant UAVs

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