The first frequency of cantilevered bars with geometric effect: a mathematical and experimental evaluation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sliding Mode Control for Active Suspension System with Data Acquisition Delay

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Robust Switched Control Design for Nonlinear Systems Using Fuzzy Models

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

Mobiliários adaptados para pessoas com paralisia cerebral: um levantamento das teses e dissertações produzidas no Brasil

The Assistive Technology makes the lives of people without disabilities more practical, but for people with disabilities it can make things possible. For these individuals can provide the conditions, making their limitations are not obstacles to their social and personal empowerment, and may contribute to their effective participation in tasks that were previously impossible, such as remaining seated correctly. A segment on which the necessary assistive technology works, is the adaptation of furniture such as chairs, tables, chairs-to-wheels for individuals with disabilities, as well as cerebral palsy. The study aimed to conduct a survey and brief description of theses and dissertations produced in Brazil on furniture adapted for students with cerebral palsy. We made searching in databases of libraries of major universities and federal state national banks, theses and dissertations. Nine studies were selected for description. It was concluded that there is a considerable array of professionals, both in engineering as the field of rehabilitation, to contribute in the adaptation, creation and even the manufacture of furniture for children with cerebral palsy and that the securities most studied are the chairs and their components.

Estudo do fenômeno de instabilidade de estruturas cilíndricas de paredes finas submetidas ao carregamento de pressão externa

Thin walled cylindrical shells are widely used in many areas of industry, including civil, mechanical, nuclear, marine, petroleum and aerospace engineering. The wide application of thin cylindrical shells and the importance of instability phenomenon are the motivation basis to this study, since these factors have a great importance in engineering projects. It is presented a detailed study about the instability of cylindrical shells based on theoretical calculation, which results are compared with finite elements method calculation. The loading and boundary conditions analyzed are based on the most common types verified in real engineering projects and refer respectively to lateral (external) pressure and cylinders with simply supported edges. The calculation based on the finite elements method was executed with ANSYS 13.0 software. The results obtained with this calculation are in good agreement with the analytical theory presented in the technical note NACA No 1341 (BATDORF, 1947) considering a wide range of applicability. On the other hand, the analytical method presented in the book Theory of Elastic Stability (TIMOSHENKO; GERE, 1936) has a very restrict applicability and has presented considerable deviations in a great sort of the analyzed cases

Estudo do comportamento em fadiga de uma chapa de aço microligado, grau API 5L X70

In engineering, for correct designing the structural components required for cyclical stresses, it is necessary to determine a limit of resistance to fatigue, which is the maximum amplitude of the applied tension under which the fatigue failure does not occurs after a certain number cycles. The marine environment is hostile, not only by the high pressure, corrosion, but also by low temperatures. Petrol Production units, composed of the risers (pipelines connecting the oil well to the ship), are dimensioned to remain installed for periods of 20 up to 30 years, and must therefore be prepared to support various efforts, such as tidal, wind currents and everything that is related. This paper focuses on a study on the fatigue behavior of microalloyed steel, API 5L Grade X70, used to transport oil and gas by pipelines. For analysis, we obtained the curves S-N (stress vs. number of cycles) using laboratory data collected from cylindrical longitudinal and transverse specimens used in axial fatigue test in accordance with ASTM E466. The tensile tests and microhardness were performed to characterize the mechanical properties of the samples, and it was found that the values meet the specifications of the standard API 5L. To characterize microstructurally the material, it was also made a metallographic analysis of the steel under study, and the origin of the fatigue crack was investigated with the support of a scanning electron microscope (SEM).

Influências do Projeto Baja SAE no ensino da engenharia e no desenvolvimento do aluno

This work aims to show the importance of Baja SAE Project in engineering education, as well as the development of the student, being an outstanding tool for the engineering student has an education that meets the objectives of the pedagogical university and also the guidelines Ministry of Education curriculum for engineering courses. The Baja SAE Project provides the engineering students the chance to apply in practice the knowledge acquired in the classroom, to enhance their preparation for the labor market. The student becomes involved with a real case of project development, from concept design, detailed design and construction. The Baja SAE Project redefines the position of the student as an active element in the learning process engineering, leaving behind the simple condition of receiving information. Values procedures that provide students the opportunity to learn in contexts of professional practice, while offering the opportunity to contextualize the execution of a project. From an analysis to develop personal skills, Baja SAE Project has its own characteristics and essential for professional practice, however, not specific to the engineering course. For example, capacity for teamwork, communication skills written and oral, ethical behavior, critical, overview, entrepreneurial spirit, leadership, etc

Modelo de flexibilidade de manufatura em processos de submontagem

Through observation of production process of a Vale do Paraiba’s automobile industry, one can encounter in need of improvement related to large uncertainties and variations in the production environment, a fact that inspired the search for solutions that can respond quickly to these changes. This way, the paper describes the development of a flexible manufacturing model, which aims to optimize the process in an automotive sub-assembly industry of the Paraíba Valley. The main objective is to propose a method to promote viable alternatives to easing the assembly of parallel sub performed the assembly of cars. For the construction of the model was necessary to explore concepts of flexible manufacturing and making the data presented in literature, which were vital to ensure the development of the method. The concepts discussed are usually presented at an undergraduate degree in Engineering. Data compiled by the model are able to serve as a strategic benchmark for decision making by managers. Featuring alternative response variables and uncertainties of the organizational environment, a fact that facilitates the management of human resources and productive

Análise da implantação do TPM em uma empresa do ramo farmacêutico

Through observation of the production process industries today, one can encounter the needs of the large uncertainties related improvements and changes in the production environment, a fact that inspired the search for solutions that can respond quickly to these changes. Thus, this paper describes the review of implementation of TPM (total productivity management), which aims to optimize two distinct processes in the Vale do Paraíba´s pharmaceutical industry one of through the pillar of specific improvement. The main objective is to propose an efficient alternative to proposing loss management processes by identifying and eliminating the same in a systematic process. To develop this analysis was necessary to explore concepts of TPM and tools that help in taking data, identification and clarification of the phenomena that cause failures in the process, which were essential to ensure the development of the analysis. The concepts covered are usually presented during an undergraduate degree in Engineering. Data compiled by the analysis are able to serve as a strategic benchmark for decision making by managers, providing alternative response variables and uncertainty of the organizational environment, a fact that facilitates the management of human resources and productive

Estudo, desenvolvimento e concepção de uma célula de carga

In engineering projects, it’s fundamental to determine the active loads in components in order to guarantee acceptable values of safety and reliability according to project specifications. On the other hand, force measurement methods might be very complex and impracticable in some cases and, so that, load cells with eletric resistance strain gages can be applied as a simple and accurate option to measure the required load. The main purpose of this paper is to present the development of a load cell that measures uniaxial forces using electric resistance strain gages without being influenced by the location of the loading in a cantilever beam. For that, it was taken as basis a secondary purpose which is to present a general study of basic and wide concepts about transducers, load cells and extensometers primarily. Information such as: loading and measurements types, characteristics of the presented devices as well as factors that influence its functioning, the most common kinds of Wheatstone bridge links, the main points of a load cell project, cements used to fix extensometers and, finally, the project itself with the tests of the built transducer are presented. By the end of this paper, all the results are shown and analyzed, concluding about the designed load cell and the work itself

Dificuldades de aprendizagem em cálculo e a relação com raciocínio lógico formal: uma análise no ensino superior

Pós-graduação em Educação - FFC

Study of some strategies for disposal of the gnss satellites

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Discrete-time sliding mode control for uncertain networked system subject to time delay

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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.