scholarly journals MODAL CONTROL OF FEEDING PROCESSES IN THE MEDIUM OF STATE SPACE AND WAVELET TRANSFORMS

2019 ◽  
pp. 46-58
Author(s):  
Anna Alekseevna Simikova ◽  
Boris Andreevich Fedosenkov ◽  
Denis Borisovich Fedosenkov
Keyword(s):  
Control System ◽  
State Space ◽  
Real Time ◽  
Flow Rate ◽  
The State ◽  
Transient Processes ◽  
Modal Control ◽  
Frequency Distributions ◽  
Time Frequency ◽  
Computer Aided

The article presents the essential aspects of designing and operational functioning of computer-aided modal control systems, using the example of a control system for feeding processes in а mixture-producing set. The object of study is the structure of feeding devices unit and transient processes during feeding. The subjects of research are the issues of designing and creating a computer-aided modal control system ( CMCS ) which operates in the mode of tunable parametrically non-stationary in frequency transient processes ( TP ). In this case, the scalar signals of the feeding devices ( FD ) material flows are formed in terms of the state space method (in the format of the internal models “input-state-output”), and monitoring of such processes is carried out in the time-frequency wavelet medium. The latter makes it possible to analyze the processes occurring in the CMCS at a semantically transparent and information-saturated level. The parameters (pulse signal off-duty ratios) of the Fourier model for the signals of a discrete-type feeder are presented, on which the nature of the dosing process depends. A model of the feeders unit is formed in terms of the state space. The 1 D -flow rate signals and their representations in the form of time-frequency distributions ( W -maps) are considered. A new concept was developed for flow rate modal control of the feeding devices unit in the frame of the mixture-producing set by introducing the definition of parametric non-stationary state of the feeding devices internal environment that takes into account the real-time variation of the multidimensional state feedback coefficient during transients in the system and for the purpose of experimental estimation of transients parameters ( here: time constants), they are determined by flow signal distributions on W -maps. The wavelet medium used in the system deals with Cohen’s class time-frequency distributions (Wigner-Ville and Choi-Williams transformations). The combination of TP -models in terms of the state space and their representation in the Wigner distribution format allows one to evaluate, set and reassign the parameters of the internal structure of the object controlled (a separate feeder or feeding devices unit) in real time in order to achieve the effect of stabilizing the ingredients flow rate in a rated mode at pre-mixing stage. The transient modes are presented in the form of processes restoring the rated modes (the so-called reverse TP) . A procedure has been developed and described for the implementation of a modal control algorithm for the feeding process, including the technology of forced localization and relocalization of the object poles under non-stationary processes in the “Executive mechanism- FD ” system, using the example of a continuous-type feeder in a transient mode on load decrease (with a downward reverse transitional process). For this mode, the calculation of the non-stationary matrix of the modal controller is presented.

scholarly journals Dynamic modal control of unmanned vehicle movement in open pit mining

2021 ◽  
Vol 44 (3) ◽  
pp. 271-284
Author(s):  
I. V. Chicherin ◽  
B. A. Fedosenkov
Keyword(s):  
Wavelet Transforms ◽  
Open Pit ◽  
Open Pit Mining ◽  
Modal Control ◽  
Frequency Distributions ◽  
Unmanned Vehicle ◽  
Time Frequency ◽  
Cohen's Class ◽  
Computer Aided ◽  
Modal Controller

The purpose of this study is to present a number of aspects in the modern concept of computer-aided dynamic modal control of unmanned quarry vehicles in open pit mining. In particular, the software and hardware module that is a part of the “Smart Quarry” global structure deals with the conditions of matching a form of specific current trajectories (their deviation to the left or right of the nominal axial trajectory) to information “trajectory” chirp signals. The study employs the methods of wavelet transforms to convert one-dimensional signals that generate unmanned vehicle current trajectories into the time-frequency distributions of Cohen’s class. The formation of unmanned vehicle current trajectories under their deviation to the left / right from the nominal axial trajectory on straight and curved routes is considered schematically. It is noted that the tracking of unmanned current trajectories on quarry routes is carried out taking into account the nature of trajectory signals. The difference between the introduced dynamic modal control of the unmanned vehicle and the static one is formulated. Some fragments displaying 1D-signals in a wavelet medium are introduced into the autonomous and external control subsystems. The computer-aided control system uses such elements of the wavelet transforms technique as Gabor wavelet functions, the wavelet matching pursuit algorithm, and Cohen’s class time-frequency distributions. The research results in formulating the criteria for forming the unmanned vehicle current trajectories by the control system in the form of its reactions to sporadic disturbances caused by the occurrence of static or dynamic obstacles on a route. The algorithm of dynamic modal control of current trajectories has been developed. The concept of forward and reverse transient processes of signals of unmanned vehicle trajectory deviation has been introduced. The estimation procedure of modal controller parameters has been described. The algorithm has been developed for modal controller matrix recalculation, which has the form of the chain of sequentially implemented matrix procedures. It should be noted in conclusion that a computer-aided system for modal control of current trajectory deviation has been developed on the basis of the performed research. It enables to implement the functions of controlling the dynamics of technological and safe movement of unmanned vehicles along the quarry routes in a conflict environment of open pit mining.

scholarly journals Adaptive Model Predictive Vibration Control of a Cantilever Beam with Real-Time Parameter Estimation

2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Gergely Takács ◽  
Tomáš Polóni ◽  
Boris Rohal’-Ilkiv
Keyword(s):  
Control System ◽  
Vibration Control ◽  
State Space ◽  
Real Time ◽  
Cantilever Beam ◽  
State Space Model ◽  
Model Parameters ◽  
Extended Kalman Filtering ◽  
Space Model ◽  
Continuous State

This paper presents an adaptive-predictive vibration control system using extended Kalman filtering for the joint estimation of system states and model parameters. A fixed-free cantilever beam equipped with piezoceramic actuators serves as a test platform to validate the proposed control strategy. Deflection readings taken at the end of the beam have been used to reconstruct the position and velocity information for a second-order state-space model. In addition to the states, the dynamic system has been augmented by the unknown model parameters: stiffness, damping constant, and a voltage/force conversion constant, characterizing the actuating effect of the piezoceramic transducers. The states and parameters of this augmented system have been estimated in real time, using the hybrid extended Kalman filter. The estimated model parameters have been applied to define the continuous state-space model of the vibrating system, which in turn is discretized for the predictive controller. The model predictive control algorithm generates state predictions and dual-mode quadratic cost prediction matrices based on the updated discrete state-space models. The resulting cost function is then minimized using quadratic programming to find the sequence of optimal but constrained control inputs. The proposed active vibration control system is implemented and evaluated experimentally to investigate the viability of the control method.

scholarly journals The wavelet transforms technique in the computer-aided system for controlling the quarry unmanned vehicles

2021 ◽  
Vol 315 ◽  
pp. 03022
Author(s):  
Ivan Chicherin ◽  
Boris Fedosenkov ◽  
Dmitriy Dubinkin ◽  
Wang Zhenbo
Keyword(s):  
Wavelet Transforms ◽  
Matching Pursuit ◽  
Effective Means ◽  
Unmanned Vehicles ◽  
Open Pit ◽  
Open Pit Mining ◽  
Frequency Distributions ◽  
One Dimensional ◽  
Time Frequency ◽  
Computer Aided

Introduction. Purpose of the work. Within the framework of the computer-aided system, a technology has been formed for the method of controlling the current trajectories (CTs) of unmanned vehicles (UMVs) when they move along routes in a quarry in open pit mining. The purpose of the presented studies is to analyze the application of a wavelet transforms technique to the problem of routing unmanned vehicles when they move along routes within open pit roads. Methodology. The results of modeling certain one-dimensional signals corresponding to the UMV current trajectories when they deviate to the left / right from a nominal axial trajectory (NAT), as well as their time-frequency representations in a wavelet medium are presented. An algorithm of the procedure for displaying scalar UMV CT control signals in a complex medium of time-frequency wavelet transforms has been developed and described. Such a transformation allows for a functionally transparent and information-capacious monitoring of the UMV movement and efficiently manage the processes of trajectory routing dump trucks in an open pit. Research results, analysis. The processes of modifying the UMV movement current trajectories under the control of the computer-aided system are generated using wavelet transforms methods. They are based on algorithms for projecting the trajectory signals with a time-dependent frequency (chirp signals) onto a set of wavelet functions as part of a wavelet thesaurus (wavelet dictionary), executing certain wavelet matching pursuit procedures, and displaying the CT scalar signals in a specific multidimensional medium of Cohen’s class time-frequency distributions. The simulation results in the form of the current trajectory (CT-) signals waveforms and their three-dimensional time-frequency representations as Wigner maps showing the UMV movement in a start-stop mode, as well as the signals of formed continuous deviation trajectories when they leave to the left and to the right from the NAT, are presented. An algorithm for the formation of 3D-representations of UMV current trajectory one-dimensional signals is presented. Conclusion. The conclusion is made that the mathematical technique of wavelet transforms is the most expedient and effective means for computer-aided monitoring and controlling the dynamics of UMV movement along routes within open pit roads.

Quadrocopter Control by Network Operator Method Based on Multi-Point Stabilization

2020 ◽  
Vol 21 (7) ◽  
pp. 428-438
Author(s):  
A. I. Diveev ◽  
E. Yu. Shmalko ◽  
O. Hussein
Keyword(s):  
Optimal Control ◽  
Control System ◽  
State Space ◽  
Operator Method ◽  
The State ◽  
Angular Motion ◽  
Stabilization System ◽  
Network Operator ◽  
System Synthesis ◽  
Phase Constraints

The paper presents a solution to the problem of optimal control of a quadrocopter under phase constraints by the numerical method of a network operator based on multi-point stabilization. According to this approach, the task of control system synthesis is initially solved. As a result, the quadrocopter is stabilized with respect to a certain point in the state space. At the second stage, a sequence of stabilization points is searched in the state space such that switching the stabilization points at fixed times ensures the movement of the quadrocopter from the initial state to the terminal state with an optimal value of the quality criterion taking into account phase constraints. To solve the problem of stabilization system synthesis, the network operator method is used. The method is numerical and, unlike the well-known analytical methods, allows to synthesize a control system automatically without a specific analysis of the right parts of the model. The method allows to find the structure and parameters of a mathematical expression in the encoded form using the genetic algorithm. The network operator code is an integer upper-triangular matrix. At the stage of solving the synthesis problem, the mathematical model of quadrocopter motion is decomposed into angular and spatial motions in order to separate control components for angular and spatial motions, respectively. The synthesized stabilization system consists of two subsystems connected in series for spatial and angular motion. As controls for spatial motion, moments around the axes and the total thrust of all quadcopter propellers were used. And the inputs for the angular motion stabilization system are the desired angles of inclination of the quadrocopter. The stabilization problem is considered as a general synthesis task for a control system. Using the network operator method, one control function is searched that provides stabilization of the object at a given point in the considered state space from the set of initial conditions. At the stage of the search for equilibrium points, the evolutionary particle swarm algorithm is used. A numerical example of solving the problem of optimal control of a quadrocopter with four phase constraints is given.

Vision-Based Real-Time Microflow-Rate Control System for Cell Analysis

2016 ◽  
Vol 28 (6) ◽  
pp. 854-861 ◽  
Author(s):  
Tadayoshi Aoyama ◽  
◽  
Amalka De Zoysa ◽  
Qingyi Gu ◽  
Takeshi Takaki ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Control System ◽  
Real Time ◽  
Flow Rate ◽  
Rate Control ◽  
Microfluidic Devices ◽  
Cell Analysis ◽  
Time Flow ◽  
On Chip ◽  
Flow Rate Control

[abstFig src='/00280006/09.jpg' width='300' text='Snapshots of particle sorting experiment using our system' ] On-chip cell analysis is an important issue for microtechnology research, and microfluidic devices are frequently used in on-chip cell analysis systems. One approach to controlling the fluid flow in microfluidic devices for cell analysis is to use a suitable pumps. However, it is difficult to control the actual flow-rate in a microfluidic device because of the difficulty in placing flow-rate sensors in the device. In this study, we developed a real-time flow-rate control system that uses syringe pumps and high-speed vision to measure the actual fluid flow in microfluidic devices. The developed flow-rate control system was verified through experiments on microparticle velocity control and microparticle sorting.

scholarly journals Scrubbing During Learning In Real-time Heuristic Search

2016 ◽  
Vol 57 ◽  
pp. 307-343 ◽  
Author(s):  
Nathan R. Sturtevant ◽  
Vadim Bulitko
Keyword(s):  
State Space ◽  
Real Time ◽  
Lower Bounds ◽  
Heuristic Search ◽  
Search Algorithm ◽  
The State ◽  
Worst Case ◽  
Heuristic Search Algorithm ◽  
Practical Performance ◽  
Theoretical Results

Real-time agent-centered heuristic search is a well-studied problem where an agent that can only reason locally about the world must travel to a goal location using bounded computation and memory at each step. Many algorithms have been proposed for this problem and theoretical results have also been derived for the worst-case performance with simple examples demonstrating worst-case performance in practice. Lower bounds, however, have not been widely studied. In this paper we study best-case performance more generally and derive theoretical lower bounds for reaching the goal using LRTA*, a canonical example of a real-time agent-centered heuristic search algorithm. The results show that, given some reasonable restrictions on the state space and the heuristic function, the number of steps an LRTA*-like algorithm requires to reach the goal will grow asymptotically faster than the state space, resulting in ``scrubbing'' where the agent repeatedly visits the same state. We then show that while the asymptotic analysis does not hold for more complex real-time search algorithms, experimental results suggest that it is still descriptive of practical performance.

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