The article presents a methodology for the synthesis of digital control systems for nonlinear objects with limiters under conditions of incomplete information. Closed-loop tracking systems with negative feedback are considered. Artificial neural networks are proposed to build a controller, which is included in series with the control object. This approach is effective when known classical methods do not allow to synthesize control. This is the case, for example, if the mathematical model is essentially nonlinear and is not fully defined. The developed methods allow us to expand the class of technical systems, for which the direct (without using various kinds of simplifications) synthesis of control laws that are close to optimal is possible. In addition, neural network controllers possess the properties of robustness, adaptivity, and are initially digital, i.e. those qualities, which are very much in demand in practice. In article main attention is given to such problems, as a choice of neural network structure for neural simulator and neural controller, construction of training sample, ensuring convergence of the process of weights correction. For training neural networks the method of back propagation of error is used as a basic one. The effectiveness of the proposed technique is demonstrated by the example of the synthesis of a neuroregulator for a specific technical object and its comparison with classical control systems. It should be noted that today neural network technologies are widespread enough in various spheres of activity. The successes demonstrated in sound processing, image processing, automatic translation, in navigation systems, in big data processing are impressive. However, their application in automatic control systems is not so widespread. The authors of this article believe that the potential of artificial neural networks can be used in this direction. It should be understood that the use of neural networks is effective only under certain conditions and properties of the control object.

The analysis of ways to improve the electroplated coating uniformity, among which the most promising for a multiassortment production is the current control, is presented in the article. The electroplating is considered as a control object and its mathematical model is described (with distributed coordinates based on the laws of Faraday and Ohm, Laplace’s partial differential equation) to current control. The search for optimal control is impossible in real time and requires lengthy preliminary calculations due to the complexity of the electroplating mathematical model. The use of associative memory in an intelligent system will make it possible to find a control that corresponds to the electroplating current state and the specified quality criterion (coating uniformity) in real time. An operation algorithm of the knowledge formation unit, which implies the use of an intelligent control system under predictable uncertainty with matrix-type associative memory, is proposed. The associative memory rows are filled based on the uniformity criterion approximation by the function and the choice of its values for given quality losses. An operation algorithm of the controller, which uses the control from the associative memory row with the closest weighted metric to the normalized values of the input variables, is considered. An operation algorithm of the quality assessment unit, which involves determining the influence of input variables on the output variable by calculating their weighting coefficients of significance, to determine the values of which the maximum values, range and maximum local changes are used for the probability of non-negativity of the output variable deviation from its given value, is proposed. A computational experiment was carried out to analyze the effectiveness of the proposed operation algorithms for the units of an intelligent electroplating control system based on associative memory in terms of the control search duration and loss in coating uniformity.

The article deals with the issues of determining the position of unmanned vehicles (UV) in tunnels in the absence of signals from global navigation satellite systems (GNSS) and unfavorable operating conditions, such as low light, high humidity, radioactivity and others. The authors proposes a method for navigating unmanned vehicles based on the phenomenon of electromagnetic induction. On board the unmanned vehicle there is a high-frequency generator, a radio transmitting unit, a radio receiving unit, an information management system, and under the bearing or supporting surface of the unmanned vehicle propulsion unit there is a single-wire radio transmission line coordinated with the environment by means of an active load. The high-frequency generator transmits high-frequency current to the radio transmitting unit, which excites a single-wire radio transmission line, the single-wire radio transmission line emits a high-frequency radio signal supplied to the radio receiving unit for further conversion by the information management system into electrical control signals of an unmanned vehicle. Magnetic loops or electrical vibrators can be used as radiating antenna from the radio transmitting unit, and magnetic loops or ferrite probe excited by the high-frequency magnetic field of the radio transmission line can be used as receiving antenna. The article deals with the influence of the environment on the processes of radiation and reception of radio signals. Computer testing of the developed method was carried out with using three-dimensional electromagnetic modeling. Electrically small loop antennas located orthogonally were used to transmit and receive the radio signal. It was shown that the phase analysis of the transmission gain in both cases can provide ample information about the direction and deviation rate from the path which is set using the radio transmission line. The results of the study can be useful for the development of navigation systems for unmanned vehicles in conditions of limited availability of signals from GNSS.

At present, the requirements for the accuracy of aircraft on-board measurement systems are constantly increasing, while sensors contain various errors in signal measurement, primarily random. Noisy signals from onboard measurements can be smoothed or filtered out in a variety of ways. One of the most popular approaches is Kalman filtering, the effectiveness of which has been proven by many studies. This paper presents a comparative analysis of the extended Kalman filter (EKF) and unscented Kalman filter (UKF), used to estimate the pitch angle of an aircraft using bench modeling data. During the simulation, the normal measurement noises are also generated. According to the results obtained in this paper, it can be noted that UKF performs better when a priori knowledge about the process noise is certain. However, the efficiency of UKF in estimating the signal deteriorates when a priori knowledge about the process becomes uncertain while the performance of EKF remains stable. This is due to the fact that UKF uses more sophisticated assumptions and therefore is more sensitive to these assumptions violation. The obtained results also show that various variants of Kalman filtering remain relevant in comparison with the smoothing methods that have spread in recent years, based on the ideas of optimal control and evolutionary algorithms for numerical optimization.

Methods of the actual values of the angles of attack and slip determination in the technology of air data systems estimation using satellite navigation systems during aircraft flight tests of are stated. Also methods of parametric identification of mathematical models of on-board aerodynamic angles measurements errors are presented. The technology has been developed and implemented in the practice of flight tests at Flight Research Institute. The technology shows high efficiency of solving tasks of air data on-board systems, vertical separation systems, flight performance and takeoff and landing characteristics estimation in flight tests. The technology covers a wide range of issues of aerometric measurements, many of which have already been published. Here, attention is paid to measurements of aerodynamic angles. The features of determining the angles of attack and slip using data from air data systems, satellite and inertial navigation systems are shown. Equations for determining the angles of attack and slip during testing, factors of measurement errors, the structure of the mathematical model of the aerodynamic errors of the angle of attack on-board measurements are presented in a stationary approximation. Algorithms for solving problems in steady and unsteady modes of flight, takeoff and landing are considered. The completeness of the solution for the wind speed vector is noted. Estimates of methodological errors in determining aerodynamic angles using the technology are made. Compliance with modern requirements is showing. The effectiveness of the technology is confirmed by the materials of flight tests of a short-range aircraft. Typical examples of test materials presentation, features of measurements depending on the type of test mode, aerodynamic influence factors are shown.

The paper devotes to the development of the approach for synthesis of reorientation trajectory of a small satellite. We consider the nanosatellite angular motion described by the kinematic quaternion equations. The aerodynamic and gravitational disturbance torques are taken into account in the angular motion model. Reorientation of a small satellite occurs from some initial position. In addition, the final angular velocity components do not exceed 0.1 °/s. The control program is given as the even Fourier series. The even Fourier series were chosen due to they can describe a complex dependency accurately. The coefficients of the even Fourier series are defined by the differential evolution algorithm. Previously, this approach has shown its efficiency for the cases of normal operation of the actuators. The paper presents the approach of synthesis of reorientation trajectory in case of failure of the actuator. The problem of reorientation reduces to optimization problem of searching of 34 coefficients of the even Fourier series that provided the achievement of the desired boundary conditions. The numerical results are given that approved the possibility of solution of the reorientation problem of small satellite in case of failure of the actuator. To compare the control programs, research was made between the cases of normal operation of the actuator and failure of the actuator. The value of the control torque differs by the order of magnitude in case of failure of the actuator. Despite this, its value is achievable for the magnetic coils.