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This article discusses the main problems of the work of a forensic expert in the conditions of digitalization. In the modern world, due to the development of technology, it is necessary to exclude all negative challenges from outside, which complicate the effective work of a forensic expert. Coronavirus infection and other cataclysms have caused many companies to switch online, which is why new risks and threats to the economic security of enterprises have appeared. The purpose of the work is to consider innovative technologies during the forensic economic examination, as well as the analysis of existing innovative solutions that improve the efficiency of the forensic expert, minimize the likelihood of making mistakes by a general analysis of the data of the company in which the examination is conducted. For highly professional forensic economic expertise, it is necessary to minimize existing and possible risks and threats to the company's security associated with digitalization. The conclusion of this study is the need for regular professional development and retraining of specialists along with the development of new technologies.

The indentation of a rigid cylinder with a flat base into a viscoelastic layer situated without friction on a rigid base is considered. The interaction process consists of two stages: indentation of a cylinder at a constant speed to a certain depth and its further holding in this depth. The mechanical behavior of a viscoelastic layer is described by equations of linear viscoelasticity with relaxation functions of two types: exponential and power. The solution of the problem is based on the application of the Volterra principle and the use of an elastic solution constructed by the asymptotic “methods of large and small λ” that were developed by I. I. Vorovich and his students. On the basis of the solution obtained, the nature of the time variation in contact stresses and loads during the indentation of the cylinder has been studied for both relatively small and relatively large layer thicknesses. A comparison of the time variation of the studied quantities for two different relaxation functions and with the results of calculations based on a simplified one-dimensional model used to describe the behavior of a viscoelastic layer during indentation is performed.

Using different imaging techniques (primarily, magnetic resonance imaging or MRI) as guidance in robotic-assisted brain surgery becomes more and more wide-spread. One of important issues in this area is using these imaging technologies in online mode. For that, robotic devices that are compatible with MRI systems are required. In particular, conventional electric drives are not suitable; some alternatives should be used, such as piezoelectric drives (PED). In this paper, a robotic system is described intended to deliver a needle (cannula) to a given point by means of a PED. Dependence of the driving force generated by PED upon the needle speed is studied. In order to describe the contact interaction between the cannula and the soft tissue, a mathematical model of their interaction is developed based on modified Kelvin-Voigt approach. A phantom of porcine brain is manufactured. Experiments are carried out where the cannula was indented into the phantom. Based on the obtained experimental data, parameters of the mathematical model are identified. Numerical simulation of the insertion of the cannula into the soft tissue is performed, and the effect of parameters of the feedback control loop upon the cannula dynamics is analysed.

The plane-parallel indentation of the tool with projections into the homogeneous and inhomogeneous biological tissue is modelled. The linear elastic and two-layer half-spaces are used for tissue modelling. The time-dependence of a force applied to the instrument and dependence of the force on the indentation depth are obtained. The shape of projections and distance between them affect these dependences. The influence of speed on the load applied to the stamp is studied. It is shown that increasing the speed of penetration leads to increasing the value of the total applied force. The shape of projections affects the nature of this dependence too.