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• STABILITY OF WALKING MACHINES AND ROBOTS IN UNDERWATER CONDITIONS

  V.V. Chernyshev, I.P. Vershinina, V.V. Arykantsev

  2020-07-10

  Abstract ▼

  When carrying out underwater technical works, walking machines and robots moving along the bottom significantly surpass traditional vehicles in terms of traction and cross-country ability. The exploitation conditions of underwater walking robotic systems - a rough terrain of the seabed, slopes, weakly bearing soil, etc., determine the urgency of the problem of their stability. The paperdiscusses the results of theoretical and experimental studies aimed at ensuring the dynamic stabil-ity of walking machines and robots in underwater conditions. The novelty of the study is provided by the specific features of their operating conditions. The studies are based on the test results of the 6-legged underwater walking device MAK-1. The instability of the walking device may be caused by the gait features. Also, the loss of stability of the walking device can occur when meet-ing with an unrecognized obstacle and when overcoming slopes. Mathematical modeling of the dynamics of statically unstable gait is carried out. The main stages of the phase of movement of the device in an unstable position are analyzed. It is shown that underwater conditions, dynami-cally stable walking of a 6-legged walking device with cyclic movers is also possible in the case of independent legs drives of the right and left side. The methods of autonomous response to a meet-ing with an unrecognized obstacle are considered. Various typical situations that arise when mov-ing along an unorganized surface are analyzed. The methods of self-adaptation and self-management of legs based on fuzzy algorithms, that exclude the occurrence of emergency situa-tions, including rollover, are proposed. The features of overcoming slopes by walking vehicles in underwater conditions are considered. In traditional vehicles movement, rollover or slide downhill is possible. It is shown that on weak soils downhill slide of walking machine is unlikely. This is due to significant deformations of the soil under the supporting elements (feet) of walking machines. A method of increasing the resistance to tipping over when moving a walking device along a slope due to the separate tuning of the conditional clearance of the walking mechanisms is considered. Particular attention is paid to the stability of drilling walking platforms moving along the bottom. Their specificity is the high location of the center of mass. Possible stages of walking platforms rollover are considered. The stabilizing effect of an increased location of the center of floatation is shown. The results of the work can be demanded in the development of walking machines and robots designed for underwater technical works, for new industrial technologies for the develop-ment of the seabed resources, to ensure the antiterrorist and technological safety of underwater infrastructure objects and other works.

• FORMALIZATION OF A SET OF INFORMATIVE SIGNS THE DYNAMICS OF MANIPULATION BY CONTROL DEVICES TO SOLVING THE PROBLEM OF DIAGNOSING THE PRODUCTIVITY OF BTS OPERATORS

  A.V. Skrinnikova, N. E. Sergeev

  2021-01-19

  Abstract ▼

  Informative signs of the dynamics of manipulation by control devices such as a mouse and
  keyboard play an important role in the development of software complexes for the identification of
  biotechnical systems (BTS) operators by their individual dynamics, in solving problems of diagnostics
  of various psycho emotional states and operator productivity. It finds application in the
  spheres of technical and law enforcement security, medical and energy spheres, etc. The purpose
  of this work is to formalize a set of informative signs of the dynamics of manipulation by control
  devices to solving the problem of diagnosing the productivity of BTS operators. To achieve this
  goal, an overview of the most frequently used features is presented, the Bayesian approach is considered
  in the statistical formulation of the recognition problem, a set of informative sings of the
  dynamics of keyboard handwriting and the dynamics of mouse manipulations is formalized basedon the results of a number of works. Operator productivity forecast based on fuzzy rules based on
  selected criteria gave an accuracy of more than 90%. The advantage of using the dynamics of
  manipulation of the control devices of the BTS operators is the absence of special equipment that
  requires additional costs.

• CONSTRUCTION OF AN OPTIMAL CONTROL TRAJECTORY IN AN INTELLIGENT SYSTEM IN THE ABSENCE OF OBSERVABLE VARIABLES

  А.N. Tselykh , V. S. Vasilev , L.А. Tselykh , Е.S. Podoplelova

  224-233

  2025-07-24

  Abstract ▼

  Constructing optimal control in the complete absence of data on the system dynamics is a pressing problem. In this paper, we propose a solution to a finite-horizon linear quadratic problem (LCP) for a time-invariant system with a graph dynamics matrix. Unlike the control problem, stability and complete controllability of the system are not assumed. The construction of the control trajectory is controlled by the direction of increase in the change in the state of variables over a small number of steps, which is determined by the conditional principal eigenvector of the adjacency matrix of the graph model. The solution of classical optimal control is carried out in an autonomous mode and requires complete knowledge of the system dynamics. In the absence of complete knowledge of the system dynamics, solving optimal control problems for systems with uncertainty, including discrete linear systems, has attracted considerable interest in recent years. The main approach when complete information about the system is unavailable is the design of optimal control, in which the system parameters are initially determined, and then an algebraic equation in the dual space is solved. An important difference from the standard discrete control problem is that the control model was modified to estimate changes in the state of variables under controls transmitted through the dynamics matrix. The proposed algorithm using a graph matrix implements recurrent calculations of dynamic and adjoint equations, as well as the Powell method for solving a system of linear algebraic equations (SLAE). The authors introduced a new interpretation of the mathematical construction of the system dynamics matrix in a standard discrete control problem on a finite time interval, which can be used to design any controlled dynamic system with unobservable parameters.

• MULTYCHANEL ADAPTIVE PHASE LOCK LOOP SYSTEM FOR GNSS RECEIVER

  А. А. Cherkasova, А. Y. Shatilov

  2025-04-27

  Abstract ▼

  Satellite navigation equipment often operates under conditions of a priori uncertainty of the parameters
  of the mutual dynamics between the transmitter and the consumer and the signal-to-noise ratio of the
  received signals of satellite radio navigation systems. Classical Bayesian algorithms for Phase lock loop
  system require a priori knowledge about the parameters of the phase process dynamics and the signal-tonoise
  ratio (SNR) of the received signals. As a result, the operation of such algorithms under conditions
  other than that a priori specified is not optimal to the criterion of minimum error variance. Moreover, a
  sudden change in the signal-to-noise ratio or dynamics can lead to a tracking failure in such a system.
  The purpose of this work is to develop an optimal phase tracking system that is adaptive to the dynamics
  of the phase process and the signal-to-noise ratio in order to maintain phase tracking in the widest possible
  range of operating conditions while tracking global navigation satellite system signal. An adaptive
  multichannel phase lock loop system has been synthesized as a result of formulation and solution of signal
  processing problem in terms of the statistical synthesis theory. Adaptivity to the changing power of the
  received signal is achieved by including the signal-to-noise ratio [dBHz] in the vector of estimated filter
  parameters. Adaptability to the intensity of the phase change dynamics is achieved through the use of a
  multi-channel filtration system. Statistical modeling of an adaptive multichannel phase lock loop tracking
  system with a complex algorithm for tracking the code delay of the signal of satellite radio navigation
  systems has been carried out. The values of the sensitivity of phase tracking under various dynamic conditions
  are determined. The adaptive multichannel phase lock loop system is able to withstand an signal-tonoise
  ratio jump from 50 to 10 dBHz and back without loss of phase tracking in low dynamics conditions
  (only the drift of the reference quartz oscillator). The AMPLL system is able to withstand abrupt transitions
  of dynamics between low and high (the sinusoidal acceleration 10g and sinusoidal jerk 10 g/s) without
  loss of phase tracking under the 24 dBHz signal-to-noise ratio. Thus, in real conditions, when the dynamics
  of the GNSS receiver and the SNRs of the received signals change in an unpredictable way, the
  AMPLL system keep tracking in a much wider range of conditions than the non-adaptive PLL

• MODEL-BASED BIOMORPHIC UNDERWADER ROBOTS SYSTEM CONTROL DESIGN

  Е. Y. Smirnova, D.К. Serov, D. К. Pelmenev, N.P. Korenko, А.Y. Nikulina

  2025-04-27

  Abstract ▼

  Currently, the field of underwater robotics is actively developing to solve applied and research
  problems. One of the promising areas of underwater robots’ application is the implementation of
  bioinspired type of swimming. The use of autonomous bioinspired underwater vehicles (BUV) will potentially
  expand the scope of application of low-noise and safe for local fauna underwater robots for monitoring
  and exploring the terrain. The aim of the work is to develop and test a methodology for model-based
  design of a motion control system for biomorphic underwater robots. In this work a typical BUV design
  with oscillatory type of swimming is considered. Problematic issues of modeling the BUV dynamics, as
  well as the synthesis of their control systems are described. For BUVs with oscillatory types of swimming,
  typical technological operations are identified. Typical technological operations are chosen based on the
  design features of the BUVs and the composition of their propulsion and steering complex. A control system
  design methodology based on the combined use of numerical modeling technologies and classical
  automatic control theory is proposed. Based on the proposed methodology, numerical hydrodynamic
  BUV’s models with oscillatory types of swimming are developed. Identification computational experiments
  are conducted. The transient processes which characterize BUV’s dynamics during the performance of
  each typical operation are defined. Based on the simulation results, cybernetic simplified models of BUV’s
  based on the typical blocks of the automatic control theory are developed. Based on the cybernetic models,
  based on the numerical optimization a synthesis of BUV’s control system in accordance with the proposed
  methodology is performed. The developed algorithms are tested based on numerical hydrodynamic simulation
  results. Possible prospects for the use of the BUV’s are formulated.