Luiz Antonio Rasia

• PhD. Microelectronics
• Resarch Cordinator NUPD/DCEEng at Regional University of the Northwest of the State of Rio Grande do Sul (UNIJUÍ)

Manufacturing environmentally friendly electronic components is a major challenge for traditional microelectronics companies. Some factors make the industry polluting and pose a high risk of accidents since they employ the use of chemical or radioactive products during complex manufacturing processes and discard at end of useful life. Electronic wa...

Este trabalho apresenta uma concepção de encapsulamento para sensores baseados no efeito piezoresistivo que foram fabricados com a utilização de materiais simples e baratos, como Alumínio e Aço Inox através de processos de fabricação não automatizado. Esta concepção se trata de uma conexão e tampa que fixa a membrana circular através de parafusos....

This article shows the design of a mechanical engineering project using problem-based learning concepts. The work shows the complexity of the teaching-learning process of a complex problem such as developing, simulating, and testing a prototype of a piezoresistive pressure sensor. This type of problem is typical in theoretical-practical classes inv...

This work presents the development and characterization of a process for manufacturing test specimens using thermoplastic polyurethane (TPU) on paper substrates, which serve as elastomeric substrates for the manufacturing of piezoresistive sensor devices using the Graphite on Paper (GoP) technique. The study of piezoresistive sensor elements is bas...

Esta obra constituiu-se a partir de um processo colaborativo entre professores, estudantes e pesquisadores que se destacaram e qualificaram as discussões neste espaço formativo. Resulta, também, de movimentos interinstitucionais e de ações de incentivo à pesquisa que congregam pesquisadores das mais diversas áreas do conhecimento e de diferentes In...

In this article, a brief review is made on the development of sensor devices based on the cantilevered beam principle made of thin-film paper obtained from pencil graphite, deposited by mechanical exfoliation. The main equations are described, the electromechanical parameters are surveyed, the computational simulation is performed, the sensors unde...

Mechatronics is an interdisciplinary field of engineering sciences characterized by the integration and interconnection between mechanical engineering, electrical engineering, and computer science. Mechatronic products are mostly structurally complex, but they are an optimal solution for many fields of industry such as medicine, agriculture, agribu...

The technologies based on paper and flexible material allow developing devices for diagnostic tests of the type Point-of-Care - PoC. These technologies enable the development of sensor devices and actuators for tests and diagnostics in humans and animals, since the materials used are thin, light, flexible and inexpensive, when compared with traditi...

The internal points method (IPM-Carvalho), with regression analysis, can generate an efficient hybrid model for estimating oat grain productivity. We tested a combination of the internal points method and regression to estimate straw productivity. We also applied this methodology to forecast a harvest index in the elaboration of a hybrid model to e...

Understanding the magnitude of contribution and relationships of industrial quality components to yield by nitrogen stimulation can drive strategies with benefits to the food industry. The objective of this study is to measure and interpret the contribution and relationship dynamics of the components of oat industrial quality with grain and industr...

Solutions for harmonic problems in electrical distribution networks have been frequently discussed in the recent literature. This article evaluates the use of Arduino microcontroller system connected with the power grid to reduce harmonic distortions and power factor correction. For this, it was developed a system capable of distinguishing the harm...

RESUMEN / ABSTRACT El uso de sensores de presión comerciales genéricos para producir transmisores de presión permite disminuir los costos y desarrollar instrumentación para amplias aplicaciones, sin necesidad de fabricar el sensor. Los modelos eléctricos para sensores comerciales son una herramienta importante para el diseño de los circuitos de aco...

As the industry advances toward the Advanced Manufacturing process emerges the need for more autonomous machines in order to get more agile and efficient production. Consequently, it creates the need for the development of cheap, easily manufactured and environmentally friendly sensors. Graphite on Paper (GOP) method for producing sensors is a stro...

This paper presents the development of a smartphone application to be a human-machine interface for a solid fertilizer dosing system with electric drive for seeder-fertilizer with dosage variable rate. Many facilities are available in applications in the commerce, communications, industry and services sectors, such as Uber, whatsApp and Airbnb. How...

This paper addresses the development of an innovative design of an automatic equipment to aid in physical rehabilitation. Physical rehabilitation aims to help people with disabilities or about to get disabilities to interact with their social environment. During rehabilitation, the physiotherapist judges the training in the patient’s experience. Fo...

Resumen La mecatrónica es un campo interdisciplinario de ciencias de la ingeniería caracterizado por la integración e interconexión entre la ingeniería mecánica, la ingeniería eléctrica y la informática. Los productos mecatrónicos son en su mayoría estructuralmente complejos, pero son una solución óptima para muchos campos de la Industria como la m...

The use of generic commercial pressure sensors to produce pressure transmitters allows to reduce costs and develop instrumentation for several applications, without the need of manufacturing the sensor. Electrical models for commercial sensors are an important tool for the design of the signal conditioning circuits that these sensors need. In the t...

This work shows the design and structural analysis of a tensile testing machine for paper used as a substrate for the manufacture of piezoresistive sensors similar to strain gauges. This article also discusses the manufacturing process and the performance analysis of a low cost machine to characterize electromechanical structures made of graphite o...

The use of generic commercial pressure sensors to produce pressure transmitters allows to reduce costs and develop instrumentation for several applications, without the need of manufacturing the sensor. Electrical models for commercial sensors are an important tool for the design of the signal conditioning circuits that these sensors need. In the t...

This paper discusses the process of manufacturing and performance analysis of piezoresistive graphite sensors in paper substrate and encapsulated with epoxy resin. Graphite in thin paper films have been investigated for a wide range of applications due to their excellent electrical and mechanical properties. The processing of graphite sensor elemen...

This article introduces or designs and practices a Gantry pneumatic robotic manipulator for greenhouse automation. The prototype was built on the reduced model for sowing and harvesting vegetables using the familiar concept of agriculture. Low-cost robotic handlers can contribute to improved working conditions in family farming and enable strategie...

This paper presents a methodology for analytical calculation and computational simulation using the finite element method for piezoresistive graphite sensor element on flexible polymer substrate, A4 paper. The computer simulation aims to find the region of greatest mechanical tension and deflection of the circular diaphragm set in the circumference...

Nowadays, many people suffer from physical disabilities caused by illness or accidents. The problems in the lower limb are one of the main that interrupt the activities of daily life of these people. To assist them in the activities of daily living, many support devices for upper and lower limb movement have been developed. In this paper is propose...

This work shows the design and assembly of a machine for tensile testing of polymers, especially industrialized paper type A4 used for deposition of fine graphite films obtained from pencils. The mechanical stresses, deformations and the modulus of elasticity of the fabricated specimen are analyzed. These mechanical parameters are important for the...

This paper presents a methodology for analytical computation and computational simulation using the finite element method - FEM for a piezoresistive sensor element in flexible polymer substrate A4 paper type. The computational simulation aims to find the region of greatest mechanical stress of the clamped square diaphragm set in the four sides, whe...

This paper presents the mathematical modeling of a nonlinear system for a sloping terrain simulation bench with pneumatic actuation, as well the prototype development of the adopted dynamic system. The use of pneumatics is advantageous in agricultural machinery for its easy maintenance, its relatively low cost and good power-to-size ratio, and also...

This paper covers research on the integration of Arduino and MATLAB/Simulink applied to mechatronics systems. The goal of reading useful data on the computer by using a micro-controller board attached to different sensors is reached with block diagram programming techniques. Successful tests were conducted when reading an analog port connected to a...

This paper presents a step-by-step methodology for design and manufacturing of parts aided by the CAD/CAM system using a CNC Router available at the Innovation Center for Automatic Machines and Servo Systems (NIMASS) on the Panambi campus of UNIJUÍ University. The best practices for using CAD/CAM software, from the design of the project to the deve...

This paper presents a methodological proposal for the process of teaching and learning of kinematic modeling of robotic manipulators through the construction and use of models of robotic structures. The kinematic modeling of robots deals with the mathematical relationship between the variables of the robotic joints and the position and the orientat...

Diamond-like carbon (DLC) thin films have been investigated for a wide range of applications due to their excellent electrical and mechanical properties. In the last decade, several researches and development activities have been conducted on the use of these thin films as piezoresistors in MEMS pressure sensors. This paper provides an overview on...

This work addresses the design and the construction of an instrumentalized workbench with hydraulic motor. The primary purpose of estimating the consumed power for farm machines, as for example the power consumption on the drive shaft of a variable rate fertilizer targeted for applications in precision agriculture. The estimate of the consumed powe...

The present work addresses the development of a pneumatically driven manufacturing cell for low cost automation applications. This cell can be used in innovative applications as a low cost alternative to increase production and quality in industry. The state of the art shows that technological advances in computing have made possible a drop in equi...

Apresenta-se a identificacao experimental da nao linearidade do atrito em uma transmissao mecânica do tipo fuso de esferas no prototipo de uma junta do robo Gantry acionado por motorredutores de corrente alternada e inversores de frequencia e a posterior inclusao do mapa estatico na validacao de seu modelo dinâmico.

Neste trabalho sao mostrados os coeficientes piezoresistivos longitudinal, transversal e de cisalhamento para filmes finos de silicio policristalino tipo N e tipo P obtidos por simulacao matematica. Estes coeficientes foram avaliados considerando o plano (100) e usando solucoes analiticas estabelecidas para diafragmas circulares. Com base nos coefi...

A presenta-se a modelagem matematica das principais caracteristicas nao lineares de atrito na haste telescopica do modulo de posicionamento de um equipamento pneumatico para poda de arvores em aplicacoes de afastamento de vegetacao proxima a linhas de energia eletrica. Os resultados ilustram as caracteristicas do modelo matematico do atrito dinâmic...

A necessidade de buscar materiais alternativos para confeccionar sensores é cada dias mais evidente, neste contexto, este trabalho apresenta um estudo acerca da utilização do grafite como elemento sensor piezoresistivo, depositado em substrato polimérico flexível (papel) e encapsulado com adesivo epóxy. Os dados experimentais foram validados atravé...

Because of their outstanding characteristics, diamond-like carbon (DLC) thin films have been recognized as interesting materials for a variety of applications. For this reason, the effects of the incorporation of different elements on their fundamental properties have been the focus of many studies. In this work, nitrogen-incorporated DLC films wer...

This article presents the longitudinal piezoresistive coefficients for thin film amorphous semiconductor type a-C:H. Experimental data and mathematical models have been used in computer simulations. The results show that a reduction of the longitudinal piezoresistive coefficient occurs due to the increased concentration of impurities in the films a...

O presente trabalho trata da modelagem matematica da cinematica direta de um braco robotico com dois graus de liberdades acionado por atuadores pneumaticos. O braco robotico possui diversas aplicacoes na industria e em equipamentos agro-florestais e pode ser utilizado em atividades perigosas e insalubres como na pintura de pecas industriais. O obje...

Artigo Completo Este trabalho apresenta o desenvolvimento da modelagem matemática do comportamento dinâmico de um robô Gantry com três graus de liberdade acionado por atuadores pneumáticos, prevendo-se futuramente uma proposta de controle de posição. Este tipo de robô é muito empregado em diversas áreas da indústria, sendo bastante utilizado na man...

This article presents the longitudinal piezoresistive coefficients for thin film amorphous semiconductor type a-C:H. Experimental data and mathematical models have been used in computer simulations. The results show that a reduction of the longitudinal piezoresistive coefficient occurs due to the increased concentration of impurities in the films a...

Este trabalho apresenta o desenvolvimento de uma bancada experimental para testes de um dosador de adubo à taxa variável para aplicação na agricultura de precisão. O objetivo é projetar e construir uma bancada para a avaliação experimental do comportamento de um dosador de adubo acionado eletricamente. Os testes realizados na bancada experimental p...

This paper presents the results of research and study of the mechanical structure types of robots that are present in industrial applications. Robotic manipulators have good functionality for applications in manufacturing companies because of their characteristics such as agility, accuracy and good repeatability of movements, ensuring reliability a...

Resumo – O presente trabalho trata da validação experimental de um modelo matemático para um atuador pneumático simétrico e sem haste. Os atuadores pneumáticos possuem diversas não linearidades devido à compressibilidade do ar e ao comportamento das vazões mássicas nos orifícios da servoválvula. A modelagem matemática contribuiu para o projeto e o...

The aim of this paper is to analyze the balance of one of the classics of population dynamics models, the model of Lotka-Volterra and see how it behaves on simulations from hypothetical data. Mathematical modeling provides tools possible to transcribe, formulate, solve and analyze facts in mathematical models. Still are explored some concepts relat...

Resumo: Este artigo apresenta um novo modelo matemático de um sistema mecânico do tipo pêndulo simples com validação experimental do mesmo. O objetivo é descrever a seqüência de passos utilizados na formulação matemática do modelo, comparando dados experimentais com modelos da literatura e a partir destes, desenvolver um modelo pertinente com a rea...

This work presents the mathematical model of a special pneumatic cylinder considering the main nonlinear characteristics system and trajectory position control. The pneumatic actuator prototype and design were developed at the in NIMeP/UNIJUÍ with financial support by CELPE in ANEEL P&D Program. Computer simulations were performed using the softwar...

In recent years, the energy sector has suffered great changes both due of environmental issues due the market changes and new policies for the sector. The Energy planning is a strategic point for the sustainable development of a country. This has motivated research on clean sources of energy like solar systems and wind power plants because they are...

Silicon carbide (SiC), in bulk or film form, has been shown as a promising material to replace the silicon as sensing element in devices for harsh environments. This has motivated several studies on growth and characterization of SiC thin films on different substrates such as silicon, silicon dioxide (SiO2), aluminum nitride (AlN) and silicon nitri...

The purpose of this chapter is to present an overview on the modeling of MEMS piezoresistive sensors: accelerometers and pressure sensors. Analytical and FEA modeling of these sensors are presented. The design and modeling of MEMS sensors using FEA (Finite Element Analysis) and analytical solutions has been subject of several studies. In general, a...

The advantages of use of thin film based sensors have been frequently discussed in the literature. This has stimulated many investigations on the piezoresistive properties of metal, semiconductor and ceramic thin films in order to use them as sensing material in strain gauge or pressure sensor applications. In the present work, we report the piezor...

This paper presents the mathematical modeling of the main features nonlinear pneumatic actuator and its application in simulation of the dynamic behavior in engineering applications . The mathematical modeling of dynamic systems is important in the design of intelligent machines , since it is used for simulation purposes , controller design and the...

Amorphous silicon carbide (a-SiC) thin films have been grown on aluminum nitride (AlN) intermediate layers on (100) Si substrates by RF magnetron sputtering technique. Profilometry, four-point probe method, Rutherford backscattering spectroscopy (RBS) and Fourier transform infrared (FTIR) were employed to characterize the as-deposited SiC thin film...

This work presents an electronic board microcontroller to automatically adjust the angle of inclination of sieve of a machine harvester grains. The system uses an inclinometer sensor device such as varying the angle between -20 to +20 degrees and provides an analog output 4-20 mA. The signal is conditioned through a converter circuit current to a v...

The use of thin films as sensing elements for microsensor applications has been shown very attractive due to their low-cost fabrication, potential for integration with standard CMOS technologies and possibility of deposition on different substrate types. In particular, piezoresistive sensors based on thin films have been commonly developed because...

In order to evaluate the potential of amorphous silicon carbide (a-SiC) films for piezoresistive sensors applications, a pressure sensor has been developed based on this material. The deposition conditions and properties of a-SiC films deposited on thermally oxidized (100) Si substrates by two techniques enhanced by plasma, PECVD (plasma enhanced c...