The main challenges of aerospace industry are increased flight range, fuel, and operating costs. There is an urgent need for more efficient design methods and rational use of composite materials in order to reduce the weight of the aircraft and increase strength and reliability. The use of optimization methods, modern software, and supercomputer technologies plays a key role in shortening the product development cycle. It allows many design options to be analyzed and compared in the early design stages. This paper presents an approach to using optimization methods in conjunction with virtual tests. The Virtual Proving Ground (VPG) includes Virtual Testbeds (VTB) such as “Aerodynamics,” “Statics,” and “Dynamics.” VPG provides end-to-end transfer of results and boundary conditions between blocks and systems of automated post-processing of the results. Thus, the results of the aerodynamic tests are transferred as input data for the static strength tests. The results of static and dynamic tests allow to perform multicriterion optimization considering different loading conditions. Automated post-processing allows to track the miscellaneous parameters at every testing stage. The aim of this work is to develop an approach to optimization of a composite structures using VPG. The presented approach was developed and tested on the example of the unmanned aerial vehicle.

The article "Design optimization of aircraft structures using virtual proving ground", written by Yuriy Gorskii, Petr Gavrilov, Georgiy Nikitin, Tatiana Pautova and Aleksandr Tamm, was originally published electronically on the publisher's internet portal on 19 June 2021 without open access.

Due to the constant machine complexity increasing as well as the requirements imposed on them, the issue of ensuring their reliability is becoming more and more urgent. The main part of any machine is supporting metal structure, which state determines the state of the machine as a whole. This determines the need to diagnose structures in order to prevent failures. At present, the methods of vibration diagnostics are being widely developed, as applied to objects of various industries. Scientists’ research is aimed at studying various types of defects, vibration parameters, methods for detecting defects and assessing the residual life. The article considers the main current trends in the development of vibration diagnostics methods. The sensitivity of the dynamic structure characteristics to the presence of a defect in the form of a crack has been investigated. A finite element analysis of a steel I-beam was performed for various cases of its fixation and crack location. The dependence of the natural frequencies and amplitude-frequency characteristics of the beam on the crack size has been analyzed. It is found that the presence of a defect has the greatest effect on the frequency response of the beam.