In this paper, the cable part of a lifting device operating on a marine vessel was studied. When the object is being towed, the “the vessel – the lifting device – the cargo system” makes non-stationary motion. In this case, the parameters of the cable part of the device: the distance between the points of the wire cable hanging, the length of the wire cable, its shape, and hydrodynamic resistance are variable. In the simulation of wire rope, it is proposed to replace it in the form of a rod system. During researches the mathematical model of small fluctuations of rod system on the basis of the Lagrange equation of II sort has been developed. Using the example of two-, three- and four-rod systems from age-old equations, dependences for their own frequencies are obtained and natural forms of small vibrations are constructed. However, as the number of rods in the system increases, the number of elements and degrees of freedom increases, leading to a significant complication. Therefore, at modeling similar types of load-lifting elements, it is recommended to limit the number of rods.

В работе рассматриваются особенности преподавания химии в медицинских вузах с циклической формой обучения в условиях низкого базового уровня знаний студентов. Обращено внимание на специфику циклового обучения, сделан акцент на необходимости формирования у

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Lowering and recovery operations, as well as towing underwater and surface objects are carried out with the help of a ship winch. As a result of the impact of any external disturbances, longitudinal oscillations appear in the towing rope, whose resonant maxima may fall into the vessel’s frequency range. The longer the cable, the greater the number of resonant frequencies in the operating range. Such operating conditions of the ship’s lifting equipment have a negative impact on the operation of the ship’s power plant as a whole. In order to increase the reliability of deck lifting equipment it is proposed to use an adaptive control system that would respond in a timely manner to changes in loading. Lifting equipment of a fishing vessel with non-stationarity of dynamic processes in operation is considered as an application of such a system. There is considered a principle of operation of the adaptive hydraulic drive of a trawl winch. The important scientific and technical problem of developing a complex mathematical model of the above control system has been solved. The directions of experimental research are determined. There is proposed a laboratory unit to evaluate the influence of the parameters of a mechanical system on the dynamics of a hydraulic drive of a load-lifting device adaptive to load variability. The unit operates due to changing the number and weight of the load discs installed on the driving and driven pulleys and simulating a change in the inertial coefficient, which is typical for a trawl winch. The second direction of experimental research is the verification of the adequacy of the obtained mathematical models. There are presented the results of the verification in the form of calculated and averaged experimental dynamometer cards, which are well correlated, with deviation up to 8%.

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