Yu. N. Khizhnyakov, Associate professor of Automatics and telemechanics department, luda@at.pstu.ru, A. A. Yuazhakov, Professor of Automatics and telemechanics department, uz@at.pstu.ru, Perm State Technical University

Robust Control of Non-Deterministic Object Using Multilevel Feedback

Robust control of non-deterministic object (NO) is an urgent task, and there are different approaches to its solution. The paper considers an introduction of fuzzy feedback in the control loop of NO. The value of the feedback coefficient may range from logic zero (the gap feedback) to logic one. Process of increasing the oscillation in the control loop (NO) is controlled by the frequency of oscillation index. The numerical value of the frequency of oscillation index sets parameters of a "forbidden" circle, which includes the "dangerous" point with coordinates —1, j0. Changes in frequency response of NO will be countered by changing the parameters of a "forbidden" circle. In the control loop of the NO we introduce an adaptive nonlinear approximator (regulator). The controller is implemented on the basis of an adaptive neural fuzzificator and unit activation functions block. Activation function (sigmoidal unbalanced function) strengthen "weak" and weakening "strong" signals at the input. Adaptation of neural fuzzificator performed using neuron feedback with sequential learning. Control algorithm feedback coefficient is made on the basis of multilevel relay element (MRE). MRE controlled by duty cycle, proportional to the difference between the signals of the current and minimum values of the frequency of oscillation index. In the control loop of MO desired dynamics is provided by the adaptive fuzzy control, and stability — by fuzzy feedback. The main conclusions are the following: adaptive fuzzy controller to control the MO using neural technology is developed; control algorithm of fuzzy feedback control loop of NO is developed.
Keywords: robust stability, non-deterministic object adaptive fuzzy control, adaptive fuzzy feedback oscillation frequency component, the neuron adaptive, multilevel relay element

P. 8—15

To the contents

I. V. Nekrasov, Software solution consultant, ivannekr@mail.ru "GE Rus" Ltd. (General Electric Intelligent Platforms), Moscow

Testing a Control Algorithm for Dynamic System at Various Quantization Periods of the Discrete Approximation of the Plant

The paper discuses real-time numeric algorithmic solutions of the optimal control problem for the dynamic system. The author investigates how the effectiveness of the optimal control algorithm changes when the quantization period of the discrete approximation of the plant is set to different ratios. It is clear from the experiments that when the computational capabilities of the handling micro-chip are unlimited the optimal control problem is most effectively solved with the following algorithm parameters: minimal quantization period of the plant and maximal scope (prognosis horizon) of the discrete algorithm. This case is converted and than solved in the micro-chip as the optimization problem of maximal dimensionality. On the other hand the limitation of computing power of the microchip restricts the dimensionality of the optimization problem being solved in real-time mode — in that case the best control quality can be achieved as a result of searching the compromise point of the named algorithm parameters.
Keywords: discrete systems, optimal control, linear programming, quantization frequency, quantization period, Shennon-Kotelnikov theorem, algorithm scope, prognosis horizon, model predictive control (MPC), control process timeframe

P. 16—23

To the contents

V. I. Busurin, Professor, vibusurin@mega.ru, Liu Zhe, Postgraduate, P. S. Akhlamov, Engineer, pakhlamov@hotmail.com, N. A. Berdjugin, Engineer, ber.nikolaj2012@yandex.ru, Moscow Aviation Institute (National Research University)

Research of Gap Mechatronic Stabilization System of Scanning Profilometer of Optical Non-contact Approximation Transducer

The article describes the structure of the mechatronic system stabilization gap and mathematical model of non-contact optical approximation transducer based on optical tunneling effect.
Today so-called scanning atomic force microscopes (AFM) are widely used. The main disadvantage of AFM is very small working gap (about 10 nm to several picometers), that could cause damage to the object of measurement, breakage of the scanning head (needle), but also to inaccuracies in the model. Foreign and domestic scientists and researchers have proposed different approaches to solve this problem. In this paper we considered the option of constructing a model with a scanning profilometer with a larger gap.
Reflectivity of the transducer depending upon various design factors such as initial gap, radius of the sphere, size of the sphere is calculated and described. It is shown, that the dependence increase the radius of the sphere and the refractive index of the material of it, in case of reducing the size of a segment of the sphere and numerical apertures, leads to reduction of integral output power. Estimation of intermolecular interaction forces occurred with inverter operation approximation showed that their influence effect can be neglected. The proposed approximation transducer can be effectively used for other measurement of mechanical values, driven to nanoparanoia, such as accelerations, speeds, forces etc.
Keywords: transducer, profilometer, mechatronic system, optical tunneling, conversion function

P. 43—47

A. I. Abramov, Chief of department, x1015@mail.ru, T. A. Mazitov, Master student, rymit1991@yandex.ru, Kalashnikov Izhevsk State Technical University

Comparative Analysis of the Effectiveness of the Methods to Search the Joint Parts in Automatic Welding

This paper considers mathematical methods for finding welding point for two type of joint: pipe — plate and plate — plate. Four algorithms are offered: the correlation method — the fastest way, allows to allocate edges of details, but it is sensitive to rotations of the parts; the use of neural networks — with the right training, allows you to select the joint parts, comparable in speed to the correlation method; approximation by straight lines — fast method, allowing to find a joint of details in the presence of emissions and other insignificant distortions; approximation by straight lines and circles — the slowest algorithm, but it is insensitive to large and small distortions and emissions. The algorithms have their advantages and disadvantages, it is said that for each task, you must use the optimal method.
Keywords: MIG/MAG welding, the vision system, triangulation, the method of least squares, approximation, networks, RANSAC

P. 47—52

E. S. Lobusov, Associate professor, evgeny.lobusov@yandex.ru, A. V. Fomichev, Associate Professor, Head of Department, a.v.fomichev@bmstu.ru, Bauman Moscow State Technical University

Forming of Strapdown Inertial Navigation System Algorithms and Main Control Modes for Small-Sized Spacecraft

It is considered the forming of Strapdown Inertial Navigation System (SINS) which is the base of spacecraft control system. The main problem is accuracy one so it is necessary to use and implement integrated navigation systems. During outer space flight onboard devices measurements and external navigation aids can be introduced.
It is shown how to organize software algorithms for orientation system relying on so called kinematic principle. Different control modes may be easily realized within the scope of suggested structure. Here the kinematic loop mainly kinematic equations is the subject of investigation. So a specific attention is given to integration methods examination for kinematic equations of angular motion and ways of improving it.
The results (methods, models, software and algorithmic support) can be used when developing strapdown systems orientation and navigation of a new generation of small-sized spacecraft, as well as the development of new and modifying of existing software of small-sized spacecraft SINS.
Keywords: onboard sensors, strapdown inertial navigation system, a small-sized spacecraft, navigation and orientation control system, integration methods, correction processing scheme, the Kalman filter

P. 54—60

O. I. Kuznetsov, Postgraduate, V. M. Soldatkin, Professor, Head of department of "Devices and information-measuring system", haibylova.piis@kstu-kai.ru, Kazan national research technical university named after A. N. Tupolev (KNRTU-KAI)

The Forming Signal of Information Support of Channels of System to Prevent Critical Modes of the Helicopter Taking into Account the Criteria of Safety

Operational restrictions imposed on the parameters of the flight of the helicopter on the modes "pickup", "vortex ring", when unmanaged autorotation of helicopter, on the modes of hovering and take-off and landing modes are considered. Requirements to channel of the information-management system to prevent critical modes of the helicopter are validate.
The reasons origin of critical modes of flight of helicopter, a method of assess their level of risk with the use of private (individual parameters of flight) and integral (mode of flight in general) functions of the danger are describes.
Connection of informative functions of danger with the dynamics of helicopter's action is shown. Formulas for determining the speed of change in time and the vector of gradient of the integral function of the danger of flight helicopter on the phase coordinates of the state vector of the helicopter, the parameters of the vector of control and vector of perturbations are shown.
Methods of forming alerts, building of control algorithms and decision-making on the criteria security with the use of vector of gradient integral function the danger of mode flight helicopter are disclosed. The methodology for describing the vector of gradient of integral function of danger of the mode flight helicopter in dimensionless parametric form convenient for practical implementation in the channels of the information-management system to prevent critical modes of the helicopter are shown.
It is shown that the investigation of the behavior of the full derivative on time of the integral function of danger of mode flight helicopter, enable to make informed decisions on constructing of algorithms wheel and automatic control, providing the quickest exit from arising emergency situations. The effectiveness of the used approach are illustrated by the example mode "vortex ring".
Method of constructing algorithm proactive alarm using the informative functions of danger of mode of flight of the helicopter is disclosed, correlations for the formation of static and dynamic feed forwards.
Using lines of level parity risk is disclosed version of the construction of the indicator of safety channel information support crew in emergency situations.
Keywords: helicopter, critical modes, prevention, system, information-management, information support, channels of warning, control, decision-making, indicating, formation, methods.

P. 60—66

V. Ya. Raspopov, Head of department "Control Equipment", tgupu@yandex.ru FSBEE HPE "Tula State University"

Gyrodyn as Learning Subject of "Control Systems of Movement and Navigation" Discipline of Higher Professional Education. Part 2. Dynamics

The dynamics of the spacecraft control with the biaxialgyrodyn on the base of the three-degree-of-freedom gyroscopes and the dynamics of the uniaxial gyrodyn on the base of the two-degree-of-freedom gyroscope is shown in the article. The dynamics of the gyrodyns and the process of the spacecraft controlling is described on the base of the theory of the three-degree-offreedom astatic gyroscope. The equations of the motion are made on the base of the kinetostatics method. The analysis of the gyro-dyndinamicsis carried out on the base of the solution of differential equations, describing the gyrodyn dynamics. It is shown, that if one uses the gyrodyns on the base of the two three-degree-offreedom gyroscopes, the system "spacecraft-gyrodyn" has the guided turn of the spacecraft which eliminates its angle of list andangle of pitch deviation. To carry out the spacecraft course angle control one needs for another biaxial gyrodyn. There is shown that the guided turn of the spacecraft is accompanied with the high-frequency oscillations of the system "spacecraft — gyrodyn'' relatively the coordinates offset. The dynamics of the uniaxial gyrodyn based on the two-degree-of-freedom gyroscopeis investigated subject to the elasticity of the bearing assemblies, backlash in the reducer of the gyroscope bracket drive, the dynamics of the drive electric motor. The analytical dependence for the calculation of the velocity of the gyrodyn turn through the given angle relatively the axis of its bracket was received.
The analysis of the dependence of the velocity of the bracket rotation on the gyrodyn parameters was carried out. It is shown, that the transient of the bracket rotation velocity is accompanied with the high-frequency damped oscillations with the minor amplitude. The article material could be used while the creation of the training courses in the academic subject "The systems of the movement control and navigation".
Keywords: gyrodyn, gyroscope, suspension, rigidity, vibration, precession, nutation, moment, spacecraft, stabilization

P. 67—72