Tm-afm nonlinear motion control with robustness analysis to parametric errors in the control signal determination

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Control of Limit Cycle Oscillation in a Three Degrees of Freedom Airfoil Section Using Fuzzy Takagi-Sugeno Modeling

This work presents a strategy to control nonlinear responses of aeroelastic systems with control surface freeplay. The proposed methodology is developed for the three degrees of freedom typical section airfoil considering aerodynamic forces from Theodorsen's theory. The mathematical model is written in the state space representation using rational function approximation to write the aerodynamic forces in time domain. The control system is designed using the fuzzy Takagi-Sugeno modeling to compute a feedback control gain. It useds Lyapunov's stability function and linear matrix inequalities (LMIs) to solve a convex optimization problem. Time simulations with different initial conditions are performed using a modified Runge-Kutta algorithm to compare the system with and without control forces. It is shown that this approach can compute linear control gain able to stabilize aeroelastic systems with discontinuous nonlinearities.

Demonstration of non-collocated vibration control of a flexible manipulator using electrical dynamic absorbers

This paper describes an experimental study into the vibration control of a servo system comprising a servo motor and a flexible manipulator. Two modes of the system are controlled by using the servo motor and an accelerometer attached to the tip of the flexible manipulator. The control system is thus non-collocated. It consists of two electrical dynamic absorbers, each of which consists of a modal filter and, in case of an out-of-phase mode, a phase inverter. The experimental results show that each absorber acts as a mechanical dynamic vibration absorber attached to each mode and significantly reduces the settling time for the system response to a step input.

Projeto e desenvolvimento de robô cartesiano de baixo custo para manipulação de produtos em linhas de média cadência

Pós-graduação em Engenharia Elétrica - FEB

Nonlinear control in an electromechanical transducer with chaotic behaviour

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atualização do conceito de qualidade na construção civil

The quality control is of great importance for the development of any organization, mainly for providing an assurance of delivering high quality services and goods for the consumers. Quality can be defined by the word „change‟, for the company which intends to implement a quality control system must be open to changes. This can be noticed from the JURAN concept (1992 In SILVEIRA ET AL., 2002): “Quality is to fit for usage”, i.e., depending on the goal, the situation and the consumer, quality is seen in different ways, since each one has different wishes and opinions. Taking in to account the availability of means such as norms, theories and tools, that contribute for an efficient quality management system, this discrepancy of opinions and the lack of objectivity of this concept can be solved, since through the analyzes of these means one can set quality standards, i.e., market references which fulfill both consumers and builders demands. Thus, the quality concept ceases to be something so abstract, non-measurable, to become a more objective concept. Finally, the goal of this work is to analyze the quality concept through bibliographic studies and possible consumers‟ enquires, aiming at the building industry, and show how the quality, often taken as something abstract, can be a measurable and objective concept, that benefits both the consumer as well as the enterprise of this branch

Projeto de mapeamento do lead time de uma empresa multinacional do ramo sucroalcooleira: estudo de caso

Facing the competitive current market, increases the growing managerial commitment to minimize the frequent occurrence of service failures that characterized the past. Given the fact that the supply of a product in the correct location and on time, undamaged and correctly billed market requirement becomes framed the present work. Based on a case study, supported in parallel bibliographical references in the literature in a company of sugar and alcohol sector, the survey aims to measure and evaluate the real-time delivery from suppliers in order to ensure the best level of service to the company in question by suppliers, by reducing idle time of delivery, since the control system does not supply the pre-established and / or observed above, thus obtaining a better management and supply of replacement material. To assist the work, developed a project in the company in question in order to analyze and identify applications of concepts of lead time along the supply chain through an exploratory study in order to provide a beneficial outcome to the company through monitoring and performance of its suppliers, which will enable an aid to future decision-making

Concepção e Implementação de um Sistema de Controle de Arborização Urbana através da Integração de Softwares Livres e de Código Aberto

Suitable computacional tools allow to build applications that can link information to its physical location, and represent them into visual and interactive schemes, e ectively reaching the power of visual comunication. This leads the user to synthesize information in a simple and e cient way. These applications are linked to the de nition of Geographic Information System (GIS). GIS are comprised by many concepts and tools, which have the main purpose of collecting, storing, viewing and processing spatial data, obtaining the information needed for decision making. Within this context, this paper presents the Conception and Implementation of a Control System for Urban Forestry through Integration of Free and Open Source Software. This conception arose from the need of an Environmental Project developed by the Agriculture's House of the city of Regente Feij o, which has as main objectives cataloging and management of urban a orestation of the municipality. Due to this diversity of concepts, the challenge in building this system is the integration of platforms that are involved in all stages: collecting and storage of data, including maps and other spatial information, operations on the stored information, obtaining results and graphical visualization of the same. After implementation, it was possible to provide for the system users an improvement in the capacity of perception in the information analysis and facilitate the process of decision making

Multi-task control strategy for grid-tied inverters based on conservative power theory

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

SDRE control strategy applied to a nonlinear robotic including drive motor

A robotic control design considering all the inherent nonlinearities of the robot-engine configuration is developed. The interactions between the robot and joint motor drive mechanism are considered. The proposed control combines two strategies, one feedforward control in order to maintain the system in the desired coordinate, and feedback control system to take the system into a desired coordinate. The feedback control is obtained using State-Dependent Riccati Equation (SDRE). For link positioning two cases are considered. Case I: For control positioning, it is only used motor voltage; Case II: For control positioning, it is used both motor voltage and torque between the links. Simulation results, including parametric uncertainties in control shows the feasibility of the proposed control for the considered system.

Nonlinear angle control of a sectioned airfoil by using shape memory alloys

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Planejamento para a implantação da ISO 9001 em uma empresa do setor industrial

The fierce competitiveness of the current market and the sophistication of customer requirements made the commitment to quality a need within organizations. The search for quality has been carried out by the adoption of quality management systems, a formal organization that should be present throughout the organization, from the initial identification of market needs to the satisfaction of customer requirements. The methodology most commonly used for this purpose is based on the requirements of ISO 9001, latest version of 2008. Considering this scenario, was developed a case study in a small company of the industrial sector with the development of a plan for the implementation of ISO 9001. The proposed methodology involved the construction of a theoretical framework on the subject and the development of a case study with a qualitative approach. Initially, was applied a questionnaire to the representative of the organization about the company's operating procedures, activity logs held, current documentation, planning and resource management for the construction of an assessment about the adequacy of the company needs to ISO 9001. Were obtained as results the characterization of production processes and organizational structure of the company and examples of policy and objectives of quality, performance indicators, document control, system for visualization of non-compliances, among others. Finally, the benefits of adopting a quality management system based on ISO 9001 requirements for the company and its environmental issues such as increased process efficiency, less waste and greater profitability, were pointed out, and the conditions for effective certification in the future

Leveraging wireless devices for networked control systems in industrial applications

Networked control systems (NCSs) are distributed control system in which sensors, actuators and controllers are physically separated and connected through communication networks. NCS represent the evolution of networked control architectures providing greater modularity and control decentralization, ease maintenance and diagnosis and lower cost of implementation. A recent trend in this research topic is the development of NCS using wireless networks(WNCS)which enable interoperability between existing wiredand wireless systems. This paper presents the feasibility analysis of using serial to wireless converter as a wireless sensor link in NCS. In order to support this investigation, relevant performance metrics for wireless control applications such as jitter, time delay and messages lost are highlighted and calculated to evaluate the wireless converter capabilities. In addition the control performance of an implemented motor control system using the converter is analyzed. Experimental results led to the conclusion that serial ZigBee device isrecommended against the Bluetooth as it provided better metrics for control applications. However, bothdevices can be used to implement WNCS providing transmission rates and closed control loop times which are acceptable for NCS applications.Moreoverthe use of thewireless device delay in the PID controller discretization can improve the control performance of the system.

Nonlinear state estimation and control applied to a manipulator robotic including drive motor

A robotic control design considering all the inherent nonlinearities of the robot engine configuration is developed. The interactions between the robot and joint motor drive mechanism are considered. The proposed control combines two strategies, one feedforward control in order to maintain the system in the desired coordinate, and feedback control system to take the system into a desired coordinate. The feedback control is obtained using State Dependent Riccati Equation (SDRE). For link positioning two cases are considered. Case 1: For control positioning, it is only used motor voltage; Case 2: For control positioning, it is used both motor voltage and torque between the links. Simulation results, including parametric uncertainties in control shows the feasibility of the proposed control for the considered system.

A New Control Architecture for Robust Controllers in Rear Electric Traction Passenger HEVs

It is well known that control systems are the core of electronic differential systems (EDSs) in electric vehicles (EVs)/hybrid HEVs (HEVs). However, conventional closed-loop control architectures do not completely match the needed ability to reject noises/disturbances, especially regarding the input acceleration signal incoming from the driver's commands, which makes the EDS (in this case) ineffective. Due to this, in this paper, a novel EDS control architecture is proposed to offer a new approach for the traction system that can be used with a great variety of controllers (e. g., classic, artificial intelligence (AI)-based, and modern/robust theory). In addition to this, a modified proportional-integral derivative (PID) controller, an AI-based neuro-fuzzy controller, and a robust optimal H-infinity controller were designed and evaluated to observe and evaluate the versatility of the novel architecture. Kinematic and dynamic models of the vehicle are briefly introduced. Then, simulated and experimental results were presented and discussed. A Hybrid Electric Vehicle in Low Scale (HELVIS)-Sim simulation environment was employed to the preliminary analysis of the proposed EDS architecture. Later, the EDS itself was embedded in a dSpace 1103 high-performance interface board so that real-time control of the rear wheels of the HELVIS platform was successfully achieved.