Automatic Control with Experiments

Everybody has been a part of a control system at some time. Some examples of this are when driving a car, balancing a broomstick on a hand, walking or standing up without falling, taking a glass to drink water, and so on. These control systems, however,arenotautomaticcontrolsystems,asapersonisrequiredtoperformarole in it. To explain this idea, in this section some more technical examples of control systems are described in which a person performs a rol

Implementation of a Controller to Eliminate the Limit Cycle in the Inverted Pendulum on a Cart

A frequency response-based linear controller is implemented to regulate the inverted pendulum on a cart at the inverted position. The objective is to improve the performance of the control system by eliminating the limit cycle generated by the dead-zone, induced by static friction, at the actuator of the mechanism. This control strategy has been recently introduced and applied by the authors to eliminate the limit cycle in the Furuta pendulum and the pendubot systems. Hence, the main aim of the present paper is to study the applicability of the control strategy to eliminate the limit cycle in the inverted pendulum on a cart. The successful results that are obtained in experiments corroborate that the approach introduced by the authors to eliminate the limit cycle in the Furuta pendulum and pendubot is also valid for the inverted pendulum on a cart

Modelado, simulación y construcción de un robot móvil de ruedas tipo diferencial

Into the study of the mobile robotics and its different configurations, it�s possible to find different applications, such as those for entertainment, medicine, militia, rescue systems or other planets exploration. With the looking for new technological trends, the study of the mobile robotics became really important in the academic area and it�s studied by students, teachers and investigators by the intention of getting more knowledge of this branch; even though not all these studies finish satisfactorily in the implementation of a physical prototype where it�s possible to test the different control laws so that the mobile realizes autonomous movements. In this article the modeling, simulation and construction of a differential wheels mobile robot, that will serve as a prototype to try different test of the automatic control theory, being possible in this way to take into the practice the theoretical concepts related to the mobile robotics of wheels, thus as the development of investigation in this area.Dentro el estudio de la robótica móvil y sus diferentes configuraciones es posible encontrar diversas aplicaciones que van desde el entretenimiento, medicina, milicia, sistemas de rescate, hasta la exploración en otros planetas. Con la búsqueda de nuevas tendencias tecnológicas, el estudio de la robótica móvil juega un papel muy importante en el área académica y es abordada por estudiantes, profesores e investigadores con el propósito de obtener un mayor conocimiento de esta rama; sin embargo no todos estos estudios concluyen satisfactoriamente en la implementación de un prototipo físico donde se pueda realizar las pruebas de distintas leyes de control para que el móvil realice movimientos autónomos. En el presente artículo se realiza el modelado, simulación y construcción de un robot móvil de ruedas tipo diferencial, que servirá como prototipo para realizar diferentes pruebas de la teoría de control automático, pudiendo de esta forma llevar a la práctica los conceptos teóricos relacionados con la robótica móvil, así como el desarrollo de investigación en esta área

Tracking Control for Mobile Robots Considering the Dynamics of All Their Subsystems: Experimental Implementation

The trajectory tracking task in a wheeled mobile robot (WMR) is solved by proposing a three-level hierarchical controller that considers the mathematical model of the mechanical structure (differential drive WMR), actuators (DC motors), and power stage (DC/DC Buck power converters). The highest hierarchical level is a kinematic control for the mechanical structure; the medium level includes two controllers based on differential flatness for the actuators; and the lowest hierarchical level consists of two average controllers also based on differential flatness for the power stage. In order to experimentally validate the feasibility of the proposed control scheme, the hierarchical controller is implemented via a Σ–Δ-modulator in a differential drive WMR prototype that we have built. Such an implementation is achieved by using MATLAB-Simulink and the real-time interface ControlDesk together with a DS1104 board. The experimental results show the effectiveness and robustness of the proposed control scheme

Optimal Tuning of the Speed Control for Brushless DC Motor Based on Chaotic Online Differential Evolution

The efficiency in the controller performance of a BLDC motor in an uncertain environment highly depends on the adaptability of the controller gains. In this paper, the chaotic adaptive tuning strategy for controller gains (CATSCG) is proposed for the speed regulation of BLDC motors. The CATSCG includes two sequential dynamic optimization stages based on identification and predictive processes, and also the use of a novel chaotic online differential evolution (CODE) for providing controller gains at each predefined time interval. Statistical comparative results with other tuning approaches evidence that the use of the chaotic initialization based on the Lozi map included in CODE for the CATSCG can efficiently handle the disturbances in the closed-loop system of the dynamic environment

DC/DC Boost Converter–Inverter as Driver for a DC Motor: Modeling and Experimental Verification

In this paper, the modeling and the experimental verification of the “bidirectional DC/DC boost converter–DC motor” system are presented. By using circuit theory along with the model of a DC motor, the mathematical model of the system is derived. This model was experimentally tested under time-varying duty cycles obtained via the system differential flatness property. The experimental verification was carried out using Matlab-Simulink and a DS1104 board in a built prototype of the system

Robust Flatness-Based Tracking Control for a “Full-Bridge Buck Inverter–DC Motor” System

By developing a robust control strategy based on the differential flatness concept, this paper presents a solution for the bidirectional trajectory tracking task in the “full-bridge Buck inverter–DC motor” system. The robustness of the proposed control is achieved by taking advantage of the differential flatness property related to the mathematical model of the system. The performance of the control, designed via the flatness concept, is verified in two ways. The first is by implementing experimentally the flatness control and proposing different shapes for the desired angular velocity profiles. For this aim, a built prototype of the “full-bridge Buck inverter–DC motor” system, along with Matlab–Simulink and a DS1104 board from dSPACE are used. The second is via simulation results, i.e., by programming the system in closed-loop with the proposed control algorithm through Matlab–Simulink. The experimental and the simulation results are similar, thus demonstrating the effectiveness of the designed robust control even when abrupt electrical variations are considered in the system

Robust Flatness-Based Tracking Control for a “Full-Bridge Buck Inverter–DC Motor” System

By developing a robust control strategy based on the differential flatness concept, this paper presents a solution for the bidirectional trajectory tracking task in the “full-bridge Buck inverter–DC motor” system. The robustness of the proposed control is achieved by taking advantage of the differential flatness property related to the mathematical model of the system. The performance of the control, designed via the flatness concept, is verified in two ways. The first is by implementing experimentally the flatness control and proposing different shapes for the desired angular velocity profiles. For this aim, a built prototype of the “full-bridge Buck inverter–DC motor” system, along with Matlab–Simulink and a DS1104 board from dSPACE are used. The second is via simulation results, i.e., by programming the system in closed-loop with the proposed control algorithm through Matlab–Simulink. The experimental and the simulation results are similar, thus demonstrating the effectiveness of the designed robust control even when abrupt electrical variations are considered in the system

Modelado y control de un robot móvil tipo newt en la tarea de seguimiento de trayectoria

En este trabajo se presenta una derivación del modelo cinemático de un robot móvil de ruedas tipo Newt, mediante la teoría Lagrangiana de la mecánica clásica. Considerando el modelo cinemático del móvil obtenido, se propone un control sencillo basado en linealización de entrada-salida que permite llevar a las variables de estado (x, y, ?) a que sigan una trayectoria nominal (x*, y*, ?*), bajo la condición de que el móvil se encuentra inicialmente sobre un punto de esta trayectoria, que sin pérdida de generalidad se elige como (0, 0, 0). De esta forma se lleva a cabo la tarea de control de seguimiento de trayectoria del móvil. El desempeño de la estrategia de control propuesta para el robot móvil tipo Newt se verifica mediante simulaciones computacionales.In this paper we obtain the kinematic model of a Newt mobile robot by using a Lagrangian approach. We take into account this kinematic model to design a simple controller for trajectory tracking of both robot position and robot orientation. Input-output linearization is the main tools that we use to design this controller. We verify performance of the closed loop system by means of numerical simulations