There is studied the mathematical foundations of the synthesis methodology in the engineering interpretation of a number of popular feedback control systems and the reasons for the impracticability of the results due to the appearance in the synthesis equations of pure differentiation operators and sources of various types of roughness violation. The global reason for the increasingly accelerated divergence of control theory from practice is associated with the impact on creative thinking such as mutation, incompatibility, randomness, fuzziness, asymmetry which underlies the evolution of synergetic systems. Both the "methodological crisis" and a number of seemingly insignificant engineering inconsistencies lead to a decrease in the planned efficiency of the developed control systems. There is a tendency to solve this practical problem through its excessive mathematization. As a result, there is nonsense — "the more mathematics, the worse", which leads to a "mathematical labyrinth", to exit from which the mathematical apparatus becomes more and more complicated until the creation of a new theory. It is shown that the use of even "correct" mathematical relations, which are the basis of the synthesis method, often leads to a violation of feasibility and rudeness. It is cited that the neglect of important poorly formalized technical indicators and the conditions of rudeness (robustness) when setting the problem does not allow us to obtain a constructive solution and is one of the main reasons for the discrepancy between theoretical results and practice. A number of popular directions of the classical theory of feedback control are considered: an inverse approach-compensation method, which forms the basis for constructing astatic, invariant, robust and other compensation systems; synthesis methods for systems with a finite settling time; assessment and control methods based on the concept of " inverse dynamics problems"; high gain limit systems. Violation of various types of feasibility and rudeness is demonstrated by specific examples tested on Matlab / Simulink. Computer research has made it possible to draw a number of positive conclusions that have important applied value.

This paper addresses the problem of station-keeping of a surface vessel by means of the consecutive compensator approach. The horizontal motion of the vessel is described by a dynamic model. The model is set up in vessel parallel coordinates, with three degrees of freedom: longitudinal, transverse and rotational motion. It is assumed that the vessel is fully actuated, i.e. there is a sufficient number and type of actuators and a thrust allocation system to ensure full manoeuvrability. Thus, the control can be designed with the assumption of three independent inputs and three output signals. The longitudinal motion can be considered separately, but a cross-coupling exists between the transverse and rotational kinetics. There is uncertainty both in parameters and signals, due to the vessel mass, inertia, and damping, as well as the unmeasured derivatives. The proposed control ensures station-keeping when the vessel is subjected to external disturbances. The consecutive compensator, which is based on high-gain feedback, provides robustness. Stability analysis is presented considering the cross-terms as limited disturbances. This allows proof of exponential stability. Experimental results are included from the Marine Cybernetics Laboratory (MC lab) at the Centre for Autonomous Marine Operations and Systems (A MOS) at the Norwegian University of Science and Technology (Norges teknisk-naturvitenskapelige universitet, NTNU ). Two scenarios are investigated: the scaled vessel is subjected to external disturbance, and the vessel executes the " four corner test". The experiments illustrate the applicability of the method.

Recycling of organic wastes is an extremely important and challenging environmental task. One of the promising trends in this field is the creation of multi-mode (combustion, pyrolysis and gasification) plants for processing organic wastes with production of such useful products as thermal energy and energy carriers (biocoal, bio-oil, pyrolysis resins, synthesis gas, etc.) and fertilizers. When creating such plants, the main problems include instability of the properties of a source material, its high water and ash content. This drives the developers to use non-standard equipment and atypical control algorithms, the creating of which requires a lot of experimental work to be done. At the same time, conducting field experiments is an expensive, difficult and long process that highlights the need for extensive use of mathematical and computer modeling. In this paper, mathematical models of elements of the gas-air path of the organic waste processing plant are obtained. The characteristics of the gas-air path of the plant as of an object of regulation for pressure in the lower and vacuum in the upper part of the combustion chamber are determined. The gas-air flow consists of the flue and the air ducts and serves to remove flue gases from the combustion chamber and supply air needed to maintain fuel combustion. When developing new automation systems, modeling allows assessing the applied solutions accurately, simplifying and reducing the cost of their development, solving the problems of system stability, optimizing transient processes, etc. The nonlinearity of the obtained mathematical models on the "the pressure at the inlet to the n-th section air-gas flow path — the pressure at the outlet of the n-th section of the air-gas flow path" channels, the nonstationarity of objects of control and dependence of their dynamic characteristics on operating mode of the plant are determined. Due to developed models, the two-way relationship of the gas and air paths has been revealed. When modeling, the gas-air flow of the plant is divided into several sections for which the mathematical models are obtained. They are required to synthesize controllers of flue gases vacuum in the upper part and the air pressure in the lower part of the combustion chamber.

The problem of robust synchronization of the electrical power network with unknown parameters is considered in the present paper. The load angles of each generator with superimposed additive high frequency noises are available for measurement. An algorithm has been synthesized to reduce the influence of noises on measurement signals and to ensure synchronization of the network in normal mode and in emergency situations associated with a sudden change in the conuctivity of power lines. To synthesize the control algorithm, the new approach is used which makes it possible to independently control the quality of noise filtering and the quality of the stabilization error of the output variable. The conditions guaranteeing the stability of the system are obtained. The simulation results have shown that the designed control system of a network of electric generators, when only noisy indications of load angles are available for measurement, provides better transient quality indicators compared to schemes of R. Ortega (France) and D. Hill (Australia), where the entire state vector is available to measurements and the parameters of the generator model are partially known. Modeling also showed that the proposed algorithm ensures the stability of a closed-loop system if there are unmodeled dynamics in network model. We also note that under conditions of random measurement noises, the control goal cannot be guaranteed due to the unlimited nature of the noises, however, the simulation results illustrate the satisfactory quality of transients with nonzero random signals in noises.

The article considers the life path of the founder of the research Institute of robotics and technical Cybernetics (RTC) Eugene Yurevich in the context of the development of Soviet and partially Russian mechatronics and robotics. It shows his personal contribution to the formation of the scientific, practical and production base of robotics in the Soviet Union and Russia.

Variants of the rotation frequency stabilization of a promising vertically axial wind-driven power plant consisting of a doubly connected stator and a rotor with blades are considered. The stator as a whole is part of the construction, axisymmetric with the rotor, and the rotor is slightly buried in the upper part of the stator — the bell. This plant can be included as an element in a complex power plant for additional and emergency power supply of both stationary and mobile objects, for example, surface robotic systems. The paper proposes to use an aerodynamic method of the rotor angular speed stabilization by controlling the positions of two variable design elements of the plant with respect to its stator. As such elements, a lower guide structure (one of the stator elements) and an aerodynamic brake flap can be used. The rearrangement of both elements positions relative to the stator changes the effective cross section for the interaction of the wind flow entering the installation with the rotor. The method of controller synthesis by the angular speed of the rotor rotation is considered in detail. A feature of this controller is the presence of two control channels with one state variable. First, it is necessary to determine the dynamic ranges of torque control on the rotor shaft for each of the variable geometry elements. This allows to correctly select the switching condition between the two control channels depending on the degree of deviation of the desired flow rate from the current speed. Based on the second-order control error equation, the desired control law of the angular rotor speed is obtained. Using the example of the problem solving of angular speed stabilization with given quality criteria, we simulated a synthesized control system for various initial data. It is shown that the constructed controller is capable of effectively countering the influence of wind disturbances in a wide range of deviations of the current speed from the frequency desired for a given target value.