Fuzzy Predictive Controller for Mobile Robot Path Tracking

IFAC Intelligent Components and Instruments for Control Applications, Annecy, France 1997This paper presents a way of implementing a Model Based Predictive Controller (MBPC) for mobile robot path-tracking. The method uses a non-linear model of mobile robot dynamics and thus allows an accurate prediction of the future trajectories. Constraints on the maximum attainable angular velocity is also considered by the algorithm. A fuzzy approach is used to implement the MBPC. The fuzzy controller has been trained using a lookup-table scheme, where the database of fuzzy-rules has been obtained automatically from a set of input-output training patterns, computed with the predictive controller. Experimental results obtained when applying the fuzzy controller to a TRC labmate mobile platform are given in the paper.Ministerio de Ciencia y Tecnología TAP95-0307Ministerio de Ciencia y Tecnología TAP96-884C

Inertial Stabilization Controller for a 2 DOF Platform

6TH IFAC SYMPOSIUM ON COST ORIENTED AUTOMATION - LCA 2001 () (.2001.BERLIN, ALEMANIA)This paper presents the controller design for the stabilization of a platform of two degrees of freedom. The purpose of this application it is to control the velocities, which are measured in a inertial frame, rejecting the disturbances associated with moving components. A gain-scheduling controller based strategy is proposed, by way of which the desired specifications are accomplished.Ministerio de Ciencia y Tecnología TAP-98-0541Unión Europea 1FD97-078

Modelling and PID Control of a Rotary Dryer

This paper describes the modelling and the PID control of a drying process. The plant uses a co-current rotary dryer to evaporate moisture of a waste product generated by olive-oil mills, called alpeorujo or two phase cake. The paper shows the development of a model based upon first principles combined with experimental results. A control strategy has been tested under simulation based on PID controllers for the main loops in this process

Mejora de la robustez de controladores LQG/LTR. Aplicación a un sistema multivariable

En el presente artículo se realiza un estudio de métodos de diseño LTR, demostrándose su utilidad con la aplicación de un sistema multivariable. El planteamiento se realiza en el espacio de estados para el cálculo e implementación de los algoritmos de control, y un tratamiento en el dominio de la frecuencia para el análisis de robustez. Se describen diferentes técnicas de diseño que emplean una filosofía de síntesis similar, conocida como LTR. Para evaluar los controladores se proponen unos indicadores de robustez. Se realizan diferentes diseños para un sistema multivariable, comparando los resultados obtenidos entre el regulador LQC/LTR convencional y un controlador LTR con estructura no basada en observador. Por último, se propone un controlador para mejorar la robustez y aplicabilidad del controlador LQR/LTR convencional.This paper makes a study of LTR (Loop Transfer Recovery) desing methods. the applicability of the methods to a multivariable system is demonstrated. State space methodos are used to implement the control algorithms and frecuency domain techniques are used to analyse its robutstness. Robustness indicators are proposed to evaluate the performance of the controllers. Different designs of a multivariable system are made, and the results obtained by a conventional LQG/LTR controller and a LTR controller without observer are compared. Finally a method is proposed to enhance the robustness and applicability of conventional LQG/LTR controllers

Longitudinal control for a laboratoty helicopter via constructive approximate backstepping

16th IFAC World Congress, Praga 2005This article presents a controller design based on Lyapunov functions, which can be applied to a class of underactuated systems that cannot be feedback linearized in a specific set point. Particularly, this design will be applied in order to control the longitudinal dynamics of a laboratory helicopter. The longitudinal system is an electro-mechanical, non-linear and underactuated system. The proposed methodology consists of modifying the model of the system using an overparametrization in such a way that the backstepping theory can be applied to the approximate system. The methodology has been tested by simulated and experimental results and it has been proved for the closed-loop system that the origin is LES

Design Optimization of the Aeronautical Sheet Hydroforming Process Using the Taguchi Method

The aluminium alloy sheet forming processes forging in rubber pad and diaphragm presses (also known as hydroforming processes) are simple and economical processes adapted to aeronautical production. Typical defects of these processes are elastic recovery, necking, and wrinkling, and they present di culties in control mainly due to property variations of the sheet material that take place during the process. In order to make these processes robust and unresponsive to material variations, a multiobjective optimization methodology based on the Taguchi method is proposed in the present study. The design of experiments and process simulation are combined in the methodology, using the nonlinear finite element method. The properties of sheet material are considered noise factors of the hydroforming process, the objective being to find a combination of the control factors that causes minimal defects to noise factors. The methodology was applied to an AA2024-T3 aluminium alloy sheet of 1 mm thickness stamping process in a diaphragm press. The results allowed us to establish the optimal pressure values, friction coeficient between sheet and block, and friction coeficient between sheet and rubber to reduce the elastic recovery variations and the minimal thickness before noise facts

Pose-estimation and control in a 3D visual servoing system

14th World Congress of IFAC, Beijing, China 1999The present work studies the case of a 3D visual servoing system composed by a robot manipulator, a CCD camera rigidly mounted on the end-effector of the robot, and other computer-based hardware. The aim of the system is to keep a desired relative position and orientation between the object and the camera, compensating for the autonomous object motion. Two existing algorithms for object's pose estimation have been implemented. Several controllers are designed and its performance evaluated along the paper

Modelling and Simulation of a Solar Power Plant with a Distributed Collectors System

IF AC Power Systems Modelling and Control Applicatio ns, Brussels, Belgium 1988This paper presents a model and computer simulation results of the distributed collectors field of a solar power plant. This plant is located in Tabernas (Almeria - Spain). The dynamic behaviour of the distributed collectors field is simulated by 100 lumped parameter submodels. Temperatures of the oil and the tube walls are modelled separately. The model also takes into account sun position, field geometry, mirrors reflectivity, solar radiation, and the inlet field oil temperature.Junta de Andalucía 07/CLM/MD

PID - Gain Scheduling Controller for a Robot Manipulator

This paper presents the implementation of an adaptive PD - Gain Scheduling controller for a six-degree-of-freedom robot manipulator. Uncoupled PD controllers are proposed for each joint where each single manipulator joint is controlled independently of the others. The gain scheduling technique enables the controller to adapt on-line the PD parameters depending on the operation conditions (essentially the robot arm position). The nonlinear dynamic model of the robot arm is then linearized discarding non-linear terms which are considered as model uncertainties, and a continuous adaptation law for the PD controller parameters is proposed. The overall control strategy can be regarded as composed by a non-linear transformation (adaptation law), followed by a linear PD regulator. This simple technique offers promising results with respect to the traditional worst-case PD design.Ministerio de Ciencia y Tecnología TAP98-054

La violación masculina en el fanfiction de temática homoerótica realizado por mujeres

El presente trabajo se centra en las producciones discursivas de tematica homoerotica creadas por fans a partir de personajes extraidos de obras literarias, audiovisuaies o de narrativa grafica comerciaies. Dichas obras, creadas y consumidas por un public0 femenino en el ciberespacio, utiiizan personajes heterosexuales en sus contextos ficcionales originaies y construyen a partir de ellos escenas o relatos basados en encuentros homosexuales. Un grupo de este tipo de productos destaca por presentar un alto componente de violencia sexual, por lo que a traves del analisis de determinadas producciones se ofrece una aproximacion a uno de 10s subgeneros del ampiio espectro argumental del slash fiction y el yaoi: el ilamado non-consensual sex (sexo no consentido). En concreto, el articulo estudia uno de 10s tropos argumentales mas comunes como es la violacion de un personaje mascuiino realizada por otro personaje, tambien masculino. Dicha situacion imaginada por mujeres autoras y consumida por mujeres lectoras pone de manifiesto el modo en que estas obras reproducen 10s roles tradicionaies de sumision femenina. Pero, ai misrno tiempo, tambien subvierten ias nociones de pornografia, poder y placer al redefinir el concept0 de masculinidad y utiiizar el cuerpo del hombre como objeto de dominio sexual