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[en] DIGITAL CONTROL OF A PNEUMATIC POSITIONING SYSTEM FOR BIOMAGNET MEASUREMENTS / [pt] CONTROLE DIGITAL DE UM SISTEMA PNEUMÁTICO DE POSICIONAMENTO PARA MEDIDAS BIOMAGNÉTICASGUILHERME SESTO KUHNER 11 December 2006 (has links)
[pt] Este trabalho apresenta uma solução para o problema de
posicionamento automático preciso de um corpo em um plano
horizontal, atendendo à restrição de não gerar campo
magnético significativo junto ao objeto a ser posicionado.
A motivação do trabalho reside na necessidade, por parte
do Laboratório de Supercondutividade Aplicada e Magnetismo
(LSAM) do Departamento de Física, de um posicionador para
experimentação em magnetocardiografia.
Inicialmente são discutidas as tecnologias de
automação aplicáveis ao problema, justificando-se a opção
por um sistema pneumático de atuação. O sistema posicionar
montado é então descrito em profundidade, abordando-se os
aspectos relacionados à geometria do problema em questão,
materiais, montagens mecânicas e o sistema de controle
digital.
A seguir é apresentada uma abordagem matemática
para o problema de controle de posição em malha fechada,
visando à definição de uma lei de controle aplicável ao
caso em estudo. Alguns resultados analíticos são obtidos
para controle de sistema caracterizados por atrito
Coulombiano, ao mesmo tempo em que se desenvolve um modelo
para simulação numérica da dinâmica de movimento do
posicionador. Com base nestas duas ferramentas, é
apresentada uma discussão sobre a aplicabilidade dos
controladores da família PID ao caso específico
considerado. Por fim, resultados reais obtidos com a lei
de controle proposta são comparadores aos resultados
simulados, mostrando-se a validade e a utilidade do modelo
teórico. / [en] This thesis presents a solution or the problem of
automatic precise positioning of na object in the
horizontal plane, not generating any significative
magnetic field in the region close to the object to be
positioned. The study presented was developed as part of
an effort to fulfill a necessity for a positioning system
for magnetocardiography experimentation in the Magnetism
and Applied Supercondutivity Laboratory of the Departament
of Physics of this University.
A discussion over applicable automation option is
presents, along with a justification for a choice of a
pneumatic actuating system. The whole precise positioning
assembly is described in detail, including subjects such
as movement geometry, material, mechanical structures and
the digital control system.
A mathematical study of the closed of the closed
loop position control problem is then developed, aiming to
define a control algorithm applicable to the problem.
Algebraic analysis is used to describe the influence of
Coulomb friction over the equations of motion of a
proportional position control system, while a model for
simulations experiments of the assembly´s positioning
dynamics is developed. These tools are used as the basis
for a discussion over the applicability of the PID
controlers in the case in study. Moreover, the behavior of
the proposed algorithm is recorded and compared to the
results of the simulations, showing the correctness and
the utility of the theoretical analysis.
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Transfer Learning for Machine DiagnosticsAl Chalati, Abdul Aziz, Naveed, Syed Asad January 2020 (has links)
Fault detection and diagnostics are crucial tasks in condition-based maintenance. Industries nowadays are in need of fault identification in their machines as early as possible to save money and take precautionary measures in case of fault occurrence. Also, it is beneficial for the smooth interference in the manufacturing process in which it avoids sudden malfunctioning. Having sufficient training data for industrial machines is also a major challenge which is a prerequisite for deep neural networks to train an accurate prediction model. Transfer learning in such cases is beneficial as it can be helpful in adapting different operating conditions and characteristics which is the casein real-life applications. Our work is focused on a pneumatic system which utilizes compressed air to perform operations and is used in different types of machines in the industrial field. Our novel contribution is to build upon a Domain Adversarial Neural Network (DANN) with a unique approach by incorporating ensembling techniques for diagnostics of air leakage problem in the pneumatic system under transfer learning settings. Our approach of using ensemble methods for feature extraction shows up to 5 % improvement in the performance. We have also performed a comparative analysis of our work with conventional machine and deep learning methods which depicts the importance of transfer learning and we have also demonstrated the generalization ability of our model. Lastly, we also mentioned a problem specific contribution by suggesting a feature engineering approach, such that it could be implemented on almost every pneumatic system and could potentially impact the prediction result positively. We demonstrate that our designed model with domain adaptation ability will be quite useful and beneficial for the industry by saving their time and money and providing promising results for this air leakage problem in the pneumatic system.
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[pt] MODELAGEM DE UM SIMULADOR DE MOVIMENTOS PARA VEÍCULOS TERRESTRES EM ESCALA / [en] MODELING OF A SCALE GROUND VEHICLES MOTION SIMULATORROBERTH WALDO ANGULO LLERENA 10 April 2012 (has links)
[pt] No presente trabalho desenvolveu-se o projeto básico de um Simulador de Movimentos em Escala, que é um equipamento utilizado para reproduzir as excitações de base provocadas pelo pavimento sobre o qual um veículo em escala trafega.
Utilizando modelos consagrados na literatura, obteve-se a representação matemática do Simulador, que é tratado como 3 subsistemas acoplados entre si, mediante a aplicação de um procedimento baseado no Fluxo de Potência.
Para o tratamento dos modelos em escala é empregada a Teoria de Similaridade, através da qual são determinados números adimensionais que relacionam o sistema real com o seu equivalente reduzido ou ampliado. São apresentadas 3 metodologias, das quais duas tradicionais, e uma outra que é conhecida como Método por Inspeção. Aplicam-se estes procedimentos a modelos de veículos com 1, 2, 4 e 7 graus de liberdade. Emprega-se também a Análise Dimensional para achar um modelo em escala do Simulador e do sistema completo, isto é um conjunto Simulador – Veículo acoplado.
Para todos os casos são realizadas simulações para os modelos real e em escala, utilizando parâmetros típicos encontrados na literatura ou em manuais de operação de equipamentos semelhantes, com o objetivos de verificar o comportamento dos sistemas, determinar a influência da redução ou ampliação do tamanho, e validar os procedimentos empregados. / [en] In this work a Scale Ground Simulator was developed. This is na equipment used to reproduce the base motion in a vehicle, due the Road where it is running.
Using a procedure based on the Power flow, coupling the 3 main Simulator subsystems, a mathematical representation for the Simulator was obtained, from classical models mentioned in the bibliography.
The scale models treatment was perfomed using the Similarity Theory, that permits the determination of non dimensional numbers relating the real system with its equivalent reduced or amplified. It was presented 3 methodologies, two of them are traditional and other one which is known as Inspection Method. These procedures were applied to 1, 2, 4, and 7 degrees of freedom vehicle models. Dimensional Analysis is also used to find scale models for the Simulator and for the complete system, i.e. the coupled set Simulator – Vehicle.
Simulations were made for all situations, in real and scale models, using typical parameters found in literature or in equipment operation manuals, aiming to verify the systems performance, to determine the size reduction or amplification influence of and to validate the procedures presented.
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Designing of A Pneumatic Cushion for Supporting Standing and Sitting ProcessYu, Mingyue, Lu, Yixuan January 2018 (has links)
As is known to all, the aging problem becomes more and more serious in recent years. The issues “get into and out of a chair”, from one of the self-care tasks of aging people named Functional mobility in ADLs (Activity of daily livings), need to be solved carefully in efficient ways to help seniors and patients who have physical problems dealing with their daily life. In this previous investigation, the existing products in the market are normally quite heavy and importable. After combined with the advantages of the existing products and some improvements in portability and comfort which is related to human engineering. A Pneumatic Cushion for Supporting Standing and Sitting Process, based on airbag and pneumatic system which has been designed in this thesis, can be used by user who has physical-trouble for standing up and sitting down. Meanwhile, after being assembled with some specific extra components, it can be used as a mobility aid device. For the whole designing process, many relevant article, video sources and websites are referred for the previous researches, including Google Scholar, BTH Digital Library and YouTube. The product was designed and analysed in Inventor 2018 and the fluid dynamic simulation has been done in Abaqus. Studies involved lifting function are selected after the survey about assist appliance and aid appliance market.
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Commercial Vehicle Air Consumption: Simulation, Validation and Recommendation / Luftförbrukning i kommersiella fordon: Simulering, validering och rekommendationerKaranja, Bethuel, Broukhiyan, Parsa January 2017 (has links)
This report details the work done in a master thesis project. The project was conducted at the Brake Performance Department at Scania CV AB. The project involves the development of a numerical model (in Matlab) that calculates and predicts air consumption in a truck under different drive cycles. The report first details tests and experiments done so as to acquire the necessary information for the development of the model. The report then presents the model that was created and delves into tests that were conducted for its validation. A model is created that allows the user to select different component combinations on the trucks along with different loading scenarios and drive cycles. Finally the model is used to evaluate air consumption in trucks during particularly strenuous cycles. The model developed is found to be reliable and accurate to with 7% with regard to amount of air consumed. With its help, several recommendations on how air consumption in commercial vehicles can be improved are made. The best components’ combination is also found and presented. / I denna rapport beskrivs ett examensarbete som genomfördes på bromsavdelningen på Scania CV AB. Projektet innefattar utveckling av en numerisk modell (i Matlab) som beräknar och förutspår luftförbrukningen i en lastbil under olika körcykler. I rapporten beskrivs det tester och experiment som gjordes för att ta fram nödvändiga uppgifter för utvecklingen av modellen. Sedan presenteras modellen som skapades och alla valideringstester som genomfördes. Modellen är gjord så att användaren kan kombinera olika komponentkombinationer för lastbilar med olika lastningskonfigurationer och körcykler. Slutligen används modellen för att utvärdera luftförbrukningen i lastbilar under särskilt ansträngande körcykler. Den utvecklade modellen visade sig vara pålitlig och korrekt med en felmarginal på 7% med avseende på mängden luft som konsumeras. Med dess hjälp kunde flera rekommendationer ges om hur luftförbrukningen i kommersiella fordon kan förbättras. De bästa komponentkombinationerna hittades också och presenteras i denna rapport
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<b>EFFICACY IN LOW-COST KINETIC APPREHENSION COUNTER DRONE SYSTEM</b>Kar Ee Ho (19183450) 25 July 2024 (has links)
<p dir="ltr">This dissertation presents the design, development, and testing environment of a low-cost, self-built ground based Counter Unmanned Aerial or Aircraft Vehicle (CUAV) system aimed at providing effective aerial security solutions in resource-limited environments. The kinetic CUAV technique was selected and identified for the current study as it is the most feasible, low-cost and reusable mitigation path as last-resort defense. Utilizing commonly available materials, including parts from online retailers and hardware stores, and incorporating a self-made pneumatic system with a reusable 3D-printed projectile and interchangeable parts design. This study explores the feasibility of cost-effective drone defense and introduces a short-range accuracy metric to evaluate the system’s trajectory behavior. Through rigorous indoor testing in Purdue University Hangar 4, the research evaluates the system's performance in terms of projectile height, range, and accuracy under various environmental conditions. A 90 degrees field of view of pneumatic launcher was tested with a small error margin comparison table to highlight on areas for potential technical refinement. TPU filament was found to be the best material for this study, with 10% infill, printing temperature in 225°C (437°F), and 70 mm/s printing speed settings for the 3D-printed projectile (4.16a). These findings in Figures 4.10, 4.11, 4.12, 4.13 will significantly advance the research of low-cost drone defense technologies by providing empirical evidence on material and design choices that will impact the system performance. Findings indicate that the system’s performance is affected by the climate temperatures, which influences its consistency in different settings. This offers practical implications for enhancing security measures against unauthorized drones using similar technology. The study fills a significant gap in current drone defense technologies with kinetic apprehension by proving that effective solutions can be both affordable and accessible. This work not only contributes to the advancement of counter drone technology but also encourages ongoing design innovation in the field, paving the way for further research and development into scalable and adaptable drone defense systems.</p>
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