More strict control quality requirements are raised to the synthesis of modern algorithmic control systems which can not be satisfied by using classical methods of systems synthesis. Also, the usage of them sometimes becomes impossible, e.g. in cases when a mathematical model of the control object is described by means of complex differential equations or in cases when the model itself is unknown. By applying the suggested synthesis methods of quasi-optimal and variable structure systems as well as algorithms, it is possible to avoid disadvantages common with classical synthesis methods.

In this final work was review the construction of Linear Induction Motors (LIM). Design performances of Linear Induction Motors (LIM) are count. In hand transporter drive LIM current unsymmetry. With MatLab was build up LIM current hinge on voltage. Structure: introduction, analytic part, research part, conclusions and suggestions, references.

<p> Control of miniature mobile robots in unconstrained environments is an ongoing challenge. Miniature robots often exhibit nonlinear dynamics and obstacle avoidance introduces significant complexity in the control problem. In order to allow for coordinated movements, the robots must know their location relative to the other robots; this is challenging for very small robots operating under severe power and size constraints. This drastically reduces on-board digital processing power and suggests the need for a robust, compact distance sensor and a mixed-signal control system using Extended Kalman Filtering and Randomized Receding Horizon Control to support decentralized coordination of autonomous mini-robots. Error analysis of the sensor suggests that system clock timing jitter is the dominant contributor for sensor measurement uncertainty. Techniques for system identification of model parameters and the design of a mixed-signal computer for mobile robot position estimation are presented. </p>

In the final dissertation a new perspective excitation systems of powerful synchronous generators, which are operating in the common energetic system, are considered, their classification and function diagram are presented. The differential equations system, transfer functions and structural diagram of excitation system, as the automatic regulation object, were obtained according to general presumtions. In the cases of deep crashs in the energetic system the mathematical description of electromechanical transient processes are very complicated and limited. In that cases the efficiency of the excitation current regulator one can be increased by using the combined algorithms of the simplex search. According to obtained expressions the synthesis diagram with adaptation and optimization blocks is created.

The theme of Master project of Electronics engineer is actual for human-computer interaction (HCI). Hand gestures provides an attractive alternative to cumbersome interface devices for human-computer interaction (HCI). In particular, visual interpretation of hand gestures can help in achieving the ease and naturalness desired for HCI. Working with computers has become an integral feature of our society. The keyboard and mouse are currently the main interfaces between man and computer. In other areas where 3D information is required, such as computer games, robotics and design, other mechanical devices such as roller-balls, joysticks and data-gloves are used. Humans communicate mainly by vision and sound, therefore, a man-machine interface would be more intuitive if it made greater use of vision and audio recognition. Another advantage is that the user not only can communicate from a distance, but need have no physical contact with the computer. However, unlike audio commands, a visual system would be preferable in noisy environments or in situations where sound would cause a disturbance. The visual system chosen was the recognition of hand gestures. There are many explorations of objects recognition in images and in video stream. Yearly improvements of computer technology lets researchers model and build more and more complex systems of recognition but it still remains a lot of unsolved problems and it is hard to decide witch system is the best. Our aim is to create a program... [to full text]

In the contemporary world of techniques, voice technologies, such as speech recognition, synthesis of speech signals, and their combined versions, acquire more and more significance. If we had a good synthesizer, we could use it widely. An example could be the reading of electronic books in voice, etc. Speech synthesizers of an older generation were quite primitive. A modern synthesis machine is not only able to read the text evenly, but to convey the emotionality as well. Speech synthesizer can raise a tone, dictate a question, and synthesize a voice of a desired timbre and speed. These features considerably enrich the speech synthesized. The aim of the research paper is to analyze the operation principles of the present speech signal synthesizers and to select the type of synthesis according to the quality indicators; prior to the compilation of Lithuanian sound set, to analyze the basics of phonetics. The features of phonemes and diphones are examined in the paper. The final result of the work is the sound set of Lithuanian language incorporating the phonemes and diphones. Synthesizer of Lithuanian language may be developed using this sound set. To implement this work, the program PRAAT was used. This software was selected due to its flexibility in the acoustic analysis of speech signals. The paper includes: 1. The analysis of general functional diagram of speech synthesis by text as well as the principles of concatenate synthesis. 2. Compilation and analysis of the... [to full text]

<p> As a subclass of hybrid systems that exhibiting both continuous and discrete dynamics, switched systems typically consists of a family of differential/difference equations and a rule that orchestrates the switching among them. Switched systems provide a useful mechanism to model complex dynamics that are subject to abrupt parameter variations and sudden changes of system configurations. Moreover, as an additional degree of freedom besides control laws, switching strategies can be utilized to improve system performance as seen in many engineering systems such as electronics, communication network, power systems, automobile and traffic control. Nevertheless, analysis and control design of switched systems are difficult and pose significant challenges for control researchers and engineers. This dissertation is dedicated to analysis and control design of switched linear systems using different switching strategies. </p><p> We first study the analysis and control problem of switched linear systems subject to actuator saturation under controlled switching. With a state-dependent switching strategy and linear differential inclusion (LDI) description of the saturated switched systems, both stabilization and output feedback control design problem are addressed. Initially, we proposed an approach based on polytopic differential inclusion (PDI) description of the saturated system. We then found two major drawbacks of this approach: 1) Computational cost grows drastically when the number of control inputs increases. 2) A conservative set mapping results in conservativeness in the synthesis conditions. Thus we proposed another approach based norm-bounded differential inclusion (NDI) characterization of the saturated system that performs better than the previous approach in these two aspects mentioned above. </p><p> We then investigate the inherent chattering behavior of the well-known state-dependent minimum switching strategy since chattering is undesirable in practice. To mitigate chattering, we developed a relaxed min-switching strategy based on the idea that switching is not forced whenever a different subsystem obtains the minimum of the Lyapunov function but held until the minimum of the Lyapunov function falls below the Lyapunov function of the active subsystem by certain margin. Based on this idea, a tunable parameter, which is related to how large the margin will be, is introduced into the switching rule. Consequently, stability analysis and control synthesis conditions are derived in terms of modified Lyapunov-Metzler inequalities. </p><p> The above mentioned relaxed min-switching strategy can effectively reduce the frequency of the switching. However, as a state-dependent switching strategy, it cannot guarantee how slow the switching can be in terms of the activation time of each subsystem. This motivates us to consider time-driven switching strategies. The so-called &rdquo;dwell-time&rdquo; and &rdquo;average dwell-time&rdquo; based switching strategies are the most popular time-driven switching strategies. Nevertheless, they are restricted to the class of switched systems with some or all stable subsystems. In view of this, a novel mixed state-dependent and time-driven switching strategy is developed for switched systems with all unstable subsystems. It guarantees the stability of the switched system with a sufficiently small dwell time by enforcing a decrement of the Lyapunov function at each switch. Moreover, it provides a more general framework of analyzing switched linear systems as it contains the min-switching and the relaxed min-switching as special cases when dwell-time is not concerned. When dwell-time is concerned, it eliminates the chattering behavior commonly observed in min-switching based designs.</p>

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1198. Adviser: Francesco Bullo. Includes bibliographical references (leaves 150-158) Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-11, Section: B, page: 7617. Adviser: Geir E. Dullerud. Includes bibliographical references (leaves 105-109) Available on microfilm from Pro Quest Information and Learning.

Thèse (M.Sc.A.)--Université de Sherbrooke (Canada), 2006. / Titre de l'écran-titre (visionné le 1 février 2007). In ProQuest dissertations and theses. Publié aussi en version papier.