This computational and experimental work is dedicated to the development of promising designs of vehicle drive shafts made of polymer composite materials. This paper analyzes the existing models of drive shafts of "Formula Student" class vehicles and substantiates the use of a carbon-fiber drive shaft with titanium tips. A manufacturing technology for such a product is also presented. Evaluation of structure performance under the action of ultimate loads was carried out by the finite element method. Prototypes of composite drive shafts were produced for further laboratory and field tests. The author proposed a new design of composite drive shafts and a method for calculating the strength of the proposed design; the results were verified by bench laboratory and field tests. From the results of this work, conclusions about the performance of the developed structures and their applicability to racing cars were drawn.

In this work, a comparative analysis of existing methods for determining the compliance of mechanical joints such as ‘composite-composite’ and ‘composite-metal’ is performed. Polymer composite materials are widely used in modern aircraft industry. As a result, it is necessary to take into account the characteristics of joints of composite aggregates with composite and metallic ones. Considering the compliance of connections in the global finite element models of structural units of aircraft allows increasing the accuracy of calculations. The use of empirical formulae can significantly reduce time and labour costs in calculating the compliance of bolted connections for use in global finite element models. In this paper we review and analyse the existing empirical dependencies. Calculation of rigidity and compliance of single-shear ‘composite-composite’ and ‘composite-metal’ joints by finite element method for small, medium and large membrane thicknesses is carried out, and the results are compared with the calculations using empirical formulae. As a result of the analysis for medium and small thicknesses it is proposed to determine the value of bolted joint flexibility by the empirical formula Boeing 1, and for large thicknesses of connecting membranes it is proposed to use empirical formula Huth.

This paper presents a comprehensive program for modelling airframe structures made of composite materials using the finite element method. The purpose of this study is to apply the comprehensive approach to the creation of models in accordance with the main directions of numerical modelling. The “computational and experimental research pyramid” and its relationship with the complex modelling program are presented. Methods for calculating aggregates and structures using micromechanics, static, dynamic and resource strength methods are described, as well as the influence of the manufacturing cycle on the final performance of a product made of a composite material. This integrated approach allows one to optimize all the stages in the design process of the aircraft. Using this approach, one can replace part of the certification tests with modelling according to the “computational and experimental research pyramid”, which will reduce the cost of certification tests.

In all real materials, energy is dissipated during deformation. You can think of it as a kind of internal friction. The load curve for the full period does not fit into a straight line. Usually, to describe the damping in the material, a model is used in terms of the hysteresis loss coefficient, since the energy losses per period depend weakly on frequency and amplitude. At the same time, the mathematical description in the loss factor model is based on complex values, that is, it implies only the case of harmonic vibration. Therefore, this damping model can only be used for frequency-domain studies. Rayleigh damping is a simple approach to forming the damping matrix as a linear combination of the mass matrix and the stiffness matrix. This damping model is unrelated to any physical loss mechanisms. In this paper, we consider a model of a mathematical pendulum for the experimental and computational determination of the damping properties of a polymer composite material. For the experimental part, a stand was designed and created that simulates the excitation of a plate made of a polymer material. The computational repetition of the experiment was performed by the finite element method and using the analytical Runge-Kutta method of the 4th and 5th order.

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