ADAPTIVE CONTROL BASED ON THE APPLICATION OF A SIMPLIFIED UNIFORM STRUCTURES AND LEARNING PROCEDURES

The present state of creating a new branch of Soft Computing (SC) for particular problem classes, possibly wider than the control of mechanical systems, is reported in this article. Like "traditional" SC il evades the development of analytical system models, and uses uniform structures, but these structures originate from various Lie groups. The advantages are a drastic reduction in size and an increase in lucidity. The generally "stochastic or semistochastic" "learning" or parameter tuning seems to be replaceable by simple explicit algebraic procedures of limited steps, too. The idea originated from mechanical systems\u27 control while considering their general internal symmetry group, and later it was further developed by using specific general features of it on a much wider scale. Convergence considerations are given for MIMO and SISO systems, too. Simulation examples are presented for the control of the inverted pendulum with the use of the Generalized Lorentzian Matrices. It is concluded that the me/hod is promising and probably imposes acceptable convergence requirements in many cases

Application of Luenberger's observer in RFPT-based adaptive control - 2014; A case study

The traditional way of thinking in controller design prefers the use of the “state space representation” introduced by R. Kalman in the early sixties of the past century. This system description is in close relationship with linear or at least partly linear system in which the linear part can be used in forming a quadratic Lyapunov function in the stability proof. In the standard model of such systems it is assumed that the state of the system is not directly observable, only certain linear functions of the state variable are directly measurable. Since such approaches introduce certain feedback gains for the state variable, observers are needed that calculate the estimation of the state variable on the basis of directly measurable quantities. The Luenberger observers solve this task via introducing a differential equation for the estimated state. In order to avoid the mathematical difficulties of Lya- punov’s “direct method” the “ Robust Fixed Point Transforma- tions (RFPT) ” were introduced in a novel adaptive technique that instead of the state space representation directly utilized the available approximate model of the system to estimate its “response function”. In this approach it was assumed that the system’s response is directly observable and an iterative sequence was generated by the use of “ Banach’s Fixed Point Theorem ” that converged to an appropriate deformation of the rough initial model to obtain precise trajectory tracking. In the present paper it is shown that the Luenberger observers and the RFPT-based mathod can be combined in a more con- ventional approach of the adaptive controllers that are designed on the basis of finding appropriate feedback gains. Illustrative simulation examples are presented to substantiate this statement

Two Cooperating Manipulators with Fractional Controllers

This paper analyzes the dynamic performance of two cooperative robot manipulators. It is studied the implementation of fractional-order algorithms in the position/force control of two cooperating robotic manipulators holding an object. The simulations reveal that fractional algorithms lead to performances superior to classical integer-order controllers

Using voting technique in mobile robot behavior coordination for goal-directed navigation

In behavior-based mobile robot, the control strategy is distributed among a set of specialized behaviors. Each behavior with particular objective runs completely independently to send commands to control the mobile robot. However, behavior with different objectives may generate conflicting command. Therefore, behavior coordination is an important issue. An intelligent voting technique is implemented to solve this problem. Each behavior votes for a set of possible actions, with vote zero is the least desired action and vote one is the most desired action. The behaviors send votes as a possibility for each action set to achieve the objectives of the behaviors. An arbiter then performs command fusion and selects the most favored action that is pareto-optimal. This will solve the action selection problem and improve the probability to succeed. This technique has been implemented on UTM AIBOT mobile robot. The experimental results are presented and the reliability of the technique is shown

Tecnica narrativa na ficcao butanica pos modernista Uma analise narratologica de "Selected Novels" de J. Fowles e P. Ackroyd

Because of my long-term fascination with Form in experimental fictional writing, in the ensuing study I propose a detailed examination of Narrative Technique such as found in the fictional work of John Fowles (1926) and Peter Ackroyd (1949), two key figures of the post modernist British literary scene; the former seen as a representative of the older generation of the 1960s, the latter as one of the most promising novelists of the younger generation of the 1980s. For my present analysis a selection of four narratives has been effectuated. Thus, having taken into account the preponderant significance of Fowles's work within British Post modernism, my choice fell on three of his novels, The Collector, from the early sixties; The French Lieutenant's Woman, from the late sixties, early seventies; A Maggot, from the mid-eighties; and on one of Ackroyd's novels, Hawks moor, from the mid-eighties. Fowles's first published fictional piece, The Collector, was chosen because in spite of what may seem a more "realistic" form I consider that many of the narrative features observed in this early text already point to more innovative, intricate narrative devices that will be further exploited in his succeeding novels. Considering that the French Lieutenant's Woman is a remarkable narrative, that it has become the post modernist British novel "par excellence", and has by now reached the status of canonical text within post modernism, my second choice was easy to make. The third narrative selected, A Maggot, the author's latest novel, is in my opinion not only Fowles's most political but also, as I hope to show, his most experimental text to date. My fourth and final choice fell on Ackroyd's Hawks moor, a historiographic meta fiction that, like Fowles's two previous texts, offers the reader a powerful reconstruction of the past in permanent confrontation with the present. As I want to look at the above-referred narratives fundamentally from a formal perspective and proceed to a detailed examination of the narrative technique employed by Fowles and Ackroyd in order to better understand the nature of post modernist fictional writing, I have selected the discipline of..Available from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1249-074 Lisboa, Portugal / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga