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A modified potential field approach is proposed for motion coordination in formations of multi-robot systems. The approach is briefly compared to related work. For the problem of moving in formation, a solution based on a directed potential field is presented. Different forces belonging to other robots and obstacles are combined and used to move each robot to its desired position inside the formation. While moving in formation, the group is able to avoid obstacles and move toward a specified target. Results of experiments are presented to illustrate the differences and improvements of this approach in comparison with the classical method.

A new approach to relative position estimation in multi-robot systems, based on information of laser scanner systems, is presented. An Extended Kalman Filter (EKF) is used to obtain continuously updated position estimation. All robots of a group use these data in order to generate one common coordinate system. Experimental results are presented, including formation movement as an example application.

This paper deals with proportional-integral observer (PI-observer) design and robust control for switched systems under arbitrary switching sequences. The proposed approach detects the existence of a switched quadratic Lyapunov function to check the asymptotic stability of switched systems. Two equivalent conditions that can guarantee the PI-observers to track the state signal are developed. Based on these conditions, we synthesize the PI-observer-based state-feedback controller stabilizing the closed-loop system. Moreover, a state-feedback controller based on a PI-observer is developed to stabilize the switched systems with uncertainties. Numerical evaluation illustrates feasibility and advantage of the PI-observer for switched systems

This paper mainly deals with the L₂-ain control of switched systems based on an output dynamical compensator. A special output dynamical compensator for switched systems is developed and a compensator-based state-feedback controller for switched systems is synthesized to guarantee the L₂-gain of closed-loop systems. Based on these assumptions, the robust control of switched systems with the L₂-gain is realized. Numerical evaluation illustrates the feasibility and advantage of this output dynamical compensator for switched systems.

The problem of image reconstruction is considered for the case when the recording system point-spread function and the recorded image are known with random errors. An efficient computational image reconstruction algorithm that uses a 2D Discrete Fourier Transform and a Fast Fourier Transform algorithm is designed. An algorithm for reliable estimation of the optimal regularization parameter is proposed to choose the regularization parameter determining the reconstruction problem solution accuracy. The reconstruction algorithm can be adapted to identify a point-spread function of dynamic image recording systems.

Algorithms for time-finite signal restoration are developed in view of feasibility of the pulse characteristic of processing devices. Functions with a lower level of side lobes than in the known functions for single-channel and two-channel restoration systems with using signal samples and time-finite signal derivatives are synthesized. Optimum functions are calculated and quasi-optimum time-finite synthesizing functions of the interpolation algorithm are proposed, which allow consideration of time constraints of initial signal realization and feasibility of the processing devices. It is found that the proposed algorithms will reduce the root-mean-square error of interpolation by 45

A method is proposed to construct nonlinear nonparametric pattern recognition algorithms for efficient solution of classification problems in the conditions of small samples. Their properties are analyzed using results of computational experiments.

A system of likelihood equations for optimal estimation of optical pulse parameters in view of shot noise is obtained. Algorithms for estimates of the amplitude and duration of a Gaussian pulse, and also its position on the time axis are found. The Cramer-Rao bounds for non-joint and joint estimates are determined.

The main results of comprehensive analysis of possible ways for solving the problem of forecasting the annual inflow of the River Ob at the site of the Novosibirsk Hydroelectric Station are considered. The research is based on ideas and methods of variant modeling. A set of probabilistic models is constructed for inflow forecasting with different accuracy and term (the period between the date of forecast and the beginning of the forecast period). Ways for future research are outlined.

Projective mapping of physical space on the spheroid domain, that is, a hyperbolic Hilbert space model, is considered. Straight lines, diameters, perpendiculars, distances, and angles on the Hilbert plane are determined. An image of visual space inside the spheroid is shown as well as its conformal mapping on the Poincare model. A formula for apparent size of the Moon elevated over the horizon is presented.