Pienikokoisen esiohjatun digitaaliventtiilin kehittäminen

This thesis describes the design, manufacturing and testing of a miniature hydraulic on/off valve. The valve has a solenoid actuated hydraulic pilot stage. The on/off valve is designed to be used as a part of a digital flow control unit (DFCU). In this thesis is first designed a miniature solenoid actuator by using analytical equations and finite element simulations. A prototype of the actuator is built and tested. The designed actuator is used for actuating the pilot stage of the designed hydraulic valve. The design process of the hydraulic valve and simulations of the valve are presented. A DFCU prototype consisting of fourdesigned on/off valves is built and tested. The main parts of the DFCU prototype are four separate layers mounted together to form the necessary features for the magnetic circuits and the flow channels of the four valves. The physical size of a single on/off valve in the prototype is about 4,5 cm3. The maximum operating pressure of the designed valve exceeds 25 MPa. The opening response time of the valve is 1,3 to 1,6 ms and the closing response time between 1,4 and 2,7 ms depending on the operating pressure. The maximum flow rate of the valve is about 9 l/min with a pressure difference of25 MPa. The designed valve meets most of the requirements placed for it. It proves that pilot operation can enable further miniaturization of hydraulic on/off valves used in digital hydraulic applications.Tämä diplomityö kuvaa pienikokoisen hydraulisen on/off venttiilin suunnittelun, rakentamisen ja testaamisen. Venttiilissä on solenoidikäyttöinen esiohjausventtiili ja se on suunniteltu käytettäväksi digitaalisen venttiilipaketin (Digital Flow Control Unit, DFCU) osana. Työssä esitellään ensin pienikokoisen solenoiditoimilaitteen suunnittelu käyttäen analyyttisia kaavoja sekä elementtimenetelmää. Toimilaitteesta rakennetaan prototyyppi ja se testataan. Suunniteltua solenoidia käytetään hydrauliventtiilin esiohjausventtiilin toimilaitteena. Hydrauliventtiilin suunnitteluprosessi ja venttiilin simuloinnit esitellään työssä. Työssä myös rakennetaan ja testataan neljä venttiiliä sisältävä venttiilipaketti. Venttiilipaketti koostuu neljästä levymäisestä osasta, jotka yhdessä muodostavat toimilaitteiden magneettipiirit sekä venttiilien virtauskanavien osat. Yksittäisen suunnitellun miniatyyriventtiilin tilavuus venttiilipaketissa on noin 4,5 cm3. Suunniteltu venttiili toimii vielä yli 25 MPa paine-erolla. Sen avautumisvasteaika on 1,3 - 1,6 ms ja sulkeutumisvasteaika 1,4 - 2,7 ms. Venttiilin maksimivirtaukseksi mitattiin noin 9 l/min 25 MPa paine-erolla. Suunniteltu venttiili täytti suurimman osan sille asetetuista suunnittelukriteereistä. Voidaan todeta, että esiohjaus mahdollistaa digitaaliventtiilien pienentämisen entisestään virtauskapasiteetin säilyessä hyvänä

磁性流体を用いたバックドライブ可能な油圧アクチュエータの開発

早大学位記番号:新7478早稲田大

Development of an automated bicycle parking spot for a smart parking system

Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáSmart parking systems are promising solutions for a set of traffic-related problems in major cities across the world. The goal of those systems is to guide users through paths in which they spend less time, resources, and release fewer greenhouse gases to find a parking spot. To this end, deployers develop Cyber-physical Systems that generally comprise embedded electronics materials, Internet of Things technologies, and Artificial Intelligence concepts. This work combines ESP8266 microcontrollers and Raspberry Pi microprocessors through MQTT communication protocol to implement its architecture, a few possible different options for the actuator are also presented, and a project for the power supply by lowcurrent photovoltaic panels is documented. Therefore, the goal is to work over some options and ideas for the physical implementation of the low-level electronics physical stage of a smart parking Cyber-physical System. The results include validated actuator options, a small photovoltaic generation sizing, and the deployment of a microcontroller routine capable of properly operate as a physical asset controller enabling scalability.Sistemas de estacionamento inteligentes são soluções promissoras para uma gama de problemas relacionados a tráfego de automóveis em grandes cidades do mundo. O objetivo destes sistemas é guiar seus usuários por caminhos pelos quais os mesmos gastam menos tempo, recursos e liberam menos gases contribuintes para o efeito estufa a fim de encontrar um local de estacionamento. Para este fim, desenvolvedores implementam Sistemas Ciber-físicos que geralmente incluem materiais de eletrônica embebida, tecnologias de Internet das Coisas e conceitos de Inteligência Artificial. Este trabalho combina os microcontroladores ESP8266 e microprocessadores Raspberry Pi pelo protocolo de comunicação MQTT a fim de implementar sua arquitetura definida, também apresenta algumas possíveis opções para a implementação de um atuador e o projeto para suprir o consumo de eletricidade por painéis fotovoltaicos de baixa corrente. Portanto, o objetivo é trabalhar em possíveis opções e ideias para a implementação física da etapa de eletrônica de baixo nível de um Sistema Ciber-físico para estacionamentos inteligentes. Os resultados incluem opções validadas de atuadores, um dimensionamento de geração fotovoltaica de baixa potência e o desenvolvimento de uma rotina para o que o microcontrolador aja como um controlador local e permita escalabilidade

Linear actuator for a submersible water pump for use in boreholes

Both the theory and the test results show that the E-core electromagnet linear actuator, which is based on the variable reluctance principle, can generate a normal force in excess of 400kNm(^-2) when there is a flux density of IT within the airgap. When the actuator is used as a driver in a submersible water pump for use in boreholes the results show that the pump is capable of pumping up to 90% of the expected value. Pressures in excess of 10 Bar have been achieved, whilst the pump was operating at frequencies up to 30Hz. The flow rate was less than 0.21s ', however improvements to the pumping system are given, and the desired 1ls ' flow rate is achievable at a delivery head of 100m.The use of linear actuators for use in submersible water pumps is a relatively new technology, and as the demand for safe clean water increases, it provides for sustainable development. The actuator utilises a D C. supply with solar panels as the source, giving the potential for global use, particularly in developing countries (the South).The design of the driver can be optimised for selected parameters. However, the development of such drivers does have limitations, the overall diameter of the pump is restricted to that of the bore-hole size, 4 or 6 inches; further the length of the pump is dictated by the straightness of the bore-hole. Consequently, design tools, for the design of E-core Variable Reluctance Linear Actuators, (VRLA), are given

Finite Element Modelling and Investigation of High Speed, Large Force and Long Lifetime Electromagnetic Actuators

The prime topic of research presented in this report is the development and use of computer-based modelling methodologies for design and performance modelling of an industrial component in the food sorting industry, exemplified in actuators used in bulk food sorting machines. Electromagnetic (EM) solenoid actuators are widely used in many applications such as the automobile, aerospace, printing and food industries where repetitive, often high-speed linear or rotating motions are required. In some of these applications they are used as high-speed 'switching' valves for switching pneumatic channels. The complex nature of electromagnetic, motional and thermal problems is discussed. The methodologies for FE modelling of such high-performance actuators are developed and discussed. These are used for modelling, design, performance evaluation and prediction of the above high-speed actuators. Modelling results showing some of the key design features of the actuators are presented in terms of force produced as a function of various design parameters. Optimization calculations for the dynamic behaviour are executed at the design process of electromagnetic actuators. Finite element method used for modelling the electromagnetic actuator model. The models are implemented in the design software Opera-2d/3d and were tested at different tasks. The capability is shown at a magnetic actuator. Magnetically controlled shape memory materials are a new way to produce motion and force. The material changes shape in a magnetic field. Usual applications of the material are actuators that produce linear motion. MSM actuator type is designed and initial investigation presented in this thesis. Finite element modelling methodologies have been developed for the design and investigation of electromagnetic and thermal behaviours of high-speed, large-force and long-lifetime solenoid actuators used as pneumatic ejector valves in optical sorting machines for bulk food sorting. Operating at frequencies between 150-300 Hz, these actuators are unique in terms of the large force they produced (8-19 N) with very long lifetime (2-5 billion cycles)

Electromagnetically-driven ultra-fast tool servos for diamond turning

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 343-351).This thesis presents the design, implementation, and control of a new class of fast tool servos (FTS). The primary thesis contributions include the design and experimental demonstration of: novel ultra-fast electromagnetic actuators, integration of these actuators in a new class of FTS, a novel real-time control computer with 1 million samples per second throughput, MIMO loop shaping techniques for parallel power amplifiers, and a novel configuration and controller tuning method for implementing adaptive feed-forward cancellation control. All of these elements have been successfully used for diamond turning of contoured surfaces. Fast tool servos (FTS) are high bandwidth positioning devices, which, in conjunction with an ultra-precision lathe and diamond tooling, can produce free form surfaces with nanometer-scale resolution, such as required in micro-optical devices and light-enhancing films. The increasing complexity of such surfaces requires more components in shorter spatial wavelengths, and thus drives simultaneously the need for high bandwidth, high acceleration and high accuracy of the FTS. Conventional FTS solutions are based on piezoelectric stacks, which are typically limited to a few micron stroke at 1 kHz operation if not operated in a resonant mode.(cont.) As a promising alternative, this thesis demonstrates electromagnetically driven solutions for fast tool servos. The key new technology in these alternative designs is a new class of ultra fast electromagnetic drivers with thousands of G's acceleration capability in continuous operation. By separating the flux-biasing surfaces from the normal-flux working surfaces, this new driver design has a number of advantages: (1) actuating force linear to both excitation current and displacement, (2) modularity and parallel operating ability, (3) full magnetic stress utilization of normal surfaces, and (4) low heat dissipation. We analyze the operation characteristics, and also provide soft magnetic material selection criteria and motor design guidelines. Based on this ultra fast driver, we designed a linear fast tool servo with the theoretical capability for 1200 G acceleration in continuous operation. To control such positioning devices at bandwidth of over 10 kHz, we developed a real-time computer architecture, utilizing three floating point digital signal processors (DSPs) in conjunction with a field-programmable gate array (FPGA) to significantly increase the processing rate.(cont.) The real-time computer prototype experimentally demonstrated 1 million samples per second real-time control execution with a total latency of 1.9 microseconds when implementing a representative control algorithm of significant complexity. This processing system has capabilities far beyond what is commercially available for such real-time high-accuracy control tasks. The power amplifier driving the FTS must supply 1 kVA (primarily reactive power) with over 100 kHz bandwidth. We present a solution of using 4 power operational amplifiers in parallel, each capable of supplying one fourth of the total power. To address the coupling issues among channels, a decoupling theory is developed to convert the associated MIMO plant into several SISO sub-plants, and thus ease the analog decentralized controller design of the power amplifier current feedback loops. In order to enhance the FTS repetitive position trajectory tracking and disturbance rejection, adaptive feed-forward cancellation is embedded into a conventional motion control loop in our system. We provide a consistent loop shaping framework and intuitive parameter tuning and trade-off guidelines for this controller structure.(cont.) Experimental results with the first prototype FTS using powder iron cores demonstrate 23 kHz closed-loop bandwidth, as low as 1.7 nm RMS error, 30 micron stroke, 500 G peak acceleration at 10 kHz open-loop operation, and 2.1 nm (0.04%) error in tracking a 3 kHz sinusoid of 16 micron p-v. (The full 1200 G capability is expected to be experimentally demonstrated by the second prototype FTS using Ni-Fe tape cores). Using this FTS, we have diamond-turned two-dimensional sinusoidal surfaces in copper and aluminum with 0.5 degree azimuthal spatial period, 160 micron radial spatial period, and 2 micron peak-to-valley amplitude, at 500 RPM spindle speed.by Xiaodong Lu.Ph.D

Sensitivity analysis and optimal design of conventional and magnnetorheological fluid brakes

Mechanical and electrical brakes have dominated the braking industry for many years and will most likely continue to do so for the foreseeable future due to their low cost and adequate operating performance, wide range of applications, vehicle engineering, civil engineering, and biomedical engineering. Simple mechanical drum brake and magnetorheological (MR) fluid brake have presented in the current work. The main objective of this work is to increase braking torque, and to develop a new optimal design of MR fluid brake with better design and design control of the MR fluid design. To do so, four important steps have been accomplished. In the first step, a mathematical modeling of the conventional frictional brake and MR fluid brake has been developed to study and specify all design parameters. In the second step, a nondimensional, closedform analysis and a Taylor series expansion have used to examine the effects of perturbing dimensionless design parameters on the overall brakes performance. In the third step, two optimal designs for MR fluid brakes have been developed by taking advantage of sensitivity analysis and the design of experiments method also known as the Taguchi method. In the fourth step, controlling a MR fluid brake is performed by using two parallel PI controls for controlling the magnetic current and MR fluid thickness simultaneously. It was concluded that sensitivity analysis is a good method for identifying the parameters that have the greatest impact on brake performance and can be used as one method for the designer to obtain an optimal design. Four nondimensional design parameters were successfully used to describe the conventional frictional brake and seven nondimensional design parameters for MR fluid brake. Only two parameters for the conventional brake and five parameters for the MR fluid brake affect the performance and the others can be neglected. Two new designs for the MR fluid brake are presented and shown to be very simple in design, low in cost by removing a lot of additional auxiliaries for the frictional brake, and easy for control. By simultaneously controlling the MR fluid thickness and the electric current, a large range of brake torque is achieved without increasing the radial envelop for the brake, and saturation conditions in one controller are compensated for by the other controller. High angular velocities of the brake are primarily controlled by increasing the MR fluid thickness, while low angular velocities are primarily controlled by increasing the electric current. Good transient responses for regulating a constant speed (high, moderate, and low), and good stability while seeking to track a sinusoidal input have been achieved. In summary, the proposed control system for the MR fluid brake has demonstrated good controllability for the MR fluid brake.Includes bibliographical reference

Model reference control for ultra-high precision positioning systems

Due to the increasing demands of high-density semiconductors, molecular biology, optoelectronics, and MEMS/NEMS in the past decades, control of ultra-high precision positioning using piezoelectricity has become an important area because of its high displacement resolution, wide bandwidth, low power consumption, and potential low cost. However, the relatively small displacement range limits its application. This work proposed a practical ultra-high precision piezoelectric positioning system with a complementary high displacement range actuation technology. Solenoids are low cost, high speed electromagnetic actuators which are commonly used in on-off mode only because of the inherent high nonlinear force-stroke characteristics and unipolar forces (push/pull) generated by the magnetic fields. In this work, an integrated positioning system based on a monolithic piezoelectric positioner and a set of push-pull dual solenoid actuators is designed for high speed and high precision positioning applications. The overall resolution can be sub-nanometer while the moving range is in millimeters, a three order of magnitude increase from using piezoelectric positioner alone. The dynamic models of the dual solenoid actuator and piezoelectric nanopositioner are derived. The main challenge of designing such positioning systems is to maintain the accuracy and stability in the presence of un-modeled dynamics, plant variations, and parasitic nonlinearities, specifically in this work, the friction and forcestroke nonlinearities of the dual solenoid actuator, and the friction, hysteresis and coupling effects of piezoelectric actuator, which are impossible to be modeled accurately and even time-varying. A model reference design approach is presented to attenuate linear as well as nonlinear uncertainties, with a fixed order controller augmenting a reference model that embeds the nominal dynamics of the plant. To improve transient characteristics, a Variable Model Reference Zero Vibration (VMRZV) control is also proposed to stabilize the system and attenuate the adverse effect of parasitic nonlinearities of micro-/nano- positioning actuators and command-induced vibrations. The speed of the ultra-high precision system with VMRZV control can also be quantitatively adjusted by systematically varying the reference model. This novel control method improves the robustness and performance significantly. Preliminary experimental data on dual solenoid system confirm the feasibility of the proposed method

Design, Modeling, Identification and Control of Mechatronic Systems

Les societats modernes plantegen nous reptes que demanden noves maneres de tractar els projectes d'enginyeria. Els enginyers han d'afrontar aquests reptes i desenvolupar solucions òptimes i eficients pels problemes clàssics i nous. Els diferents avenços produïts en la tecnologia hi poden ajudar, però una nova manera de tractar els problemes enginyerils és també necessària, no considerant únicament les diferent especialitats de l'enginyeria aïlladament. En aquest context, podem parlar de la creació d'una nova filosofia de fer enginyeria: la Mecatrònica. La Mecatrònica s'ha definit com l'aplicació de decisions complexes a l'operació de sistemes físics. La Mecatrònica ha estat també definida com la integració o sinergia de diferents disciplines de l'enginyeria. Aquestes disciplines inclouen l'enginyeria mecànica, l'enginyeria elèctrica, l'enginyeria electrònica, l'enginyeria de control, les comunicacions industrials i l'enginyeria de software. No obstant, la importància del concepte no està únicament en la definició sinó a la filosofia que hi ha al fons. És important de veure, que la Mecatrònica no és només la suma dels resultats de diferents disciplines, sinó la filosofia enginyeril per afrontar els problemes com un de sol, fent servir les eines que subministren les diferents disciplines. La present tesi es divideix en dos parts que tracten problemes de diferent natura. La primera part es titula Regles de disseny i modelat d'actuadors per l'optimització de sistemes mecatrònics i es centra en proporcionar un anàlisis detallat de diferents actuadors utilitzant un procediment general, orientat a millorar el disseny de l'actuador. S'introdueix una nova metodologia per analitzar actuadors lineals electromagnètics i hidràulics modelitzant la seves magnituds mecàniques (força, treball i desplaçament) com a funcions de la geometria i les propietats del material, estudiant l'escalabilitat (en el sentit de produir la mateixa distribució de tensions i deformacions per diferents mides). La motivació de realitzar aquest treball neix de la necessitat d'estructures i sistemes lleugers i de volum reduït, que han de ser integrats en el procediment de disseny el més aviat possible. Per tant, s'estudien les relacions geomètriques, les proporcions i les propietats dels materials que maximitzen les magnituds mecàniques de sortida dels actuadors per un volum i pes limitat, així com l'escabilitat per la seva posterior integració en estructures. Els resultats són validats mitjançant anàlisi dimensional de les expressions obtingudes i comparant els resultats numèrics amb dades d'actuadors industrials. Es considera el comportament estàtic de diferents classes d'actuadors, incloent actuadors hidràulics i electromagnètics lineals. La segona part es titula Identificació i Control d'Actuadors Piezoelèctrics. Els actuadors piezoelèctrics estan demostrant ser una solució fiable per moltes aplicacions, des del microposicionament (màquines eina, dispositius òptics o microscopis moderns) al control actiu d'estructures. La principal motivació de la segona part de la tesis és aprofundir en models per representar el comportament histerètic dels actuadors piezoelèctrics per posteriorment aplicar els models al desenvolupament de controladors pels sistemes histerètics. Es desenvolupa inicialment un estudi general dels actuadors piezoelèctrics per després tractar la seva modelització. Degut a l'elevat comportament no-lineal observat es necessita un model d'histèresis. El model de Bouc-Wen ha estat escollit i s'ha treballat en la identificació dels paràmetres del model i la seva validació. Un cop el sistema ha estat modelat, s'olinebreak ha dissenyat un nou controlador lineal i s'ha implementat en una plataforma experimental utilitzant un DSP (Processador digital de senyal). Encara que les dues parts estan clarament diferenciades, la unitat de la tesis pot ser trobada a les arrels de la Mecatrònica. La tesis tracta la resposta a una sola pregunta: Com podem millorar un sistema mecatrònic? No obstant, la resposta és doble: Dissenyant i modelant actuadors òptims considerant el sistema o estructura complet i controlant el sistema adequadament fent servir els models desenvolupats.Fast changing societies come up with new challenges that require new engineering approaches. Engineers have to face such challenges and provide novel and more efficient solutions to classical and new problems. This can be done by using different relevant advances produced in technology. Furthermore, a new way of addressing the engineering problems has to be applied, not considering only isolated engineering specialties. In this frame, we can talk about the creation of a new engineering philosophy: Mechatronics. Mechatronics has been defined as the application of complex decision making to the operation of physical systems. Mechatronics has been also defined as the integration or synergy of different engineering disciplines. Such disciplines may include Mechanical Engineering, Electrical Engineering, Electronics Engineering, Control Engineering, Industrial Communications and Software Engineering. Nevertheless, the importance of the concept does not lie only in the definition but in the philosophy behind it. It is very important to note that Mechatronics is not only the sum of the results of the different disciplines, but the engineering philosophy to face engineering problems as a whole, employing the tools provided by the different disciplines. The present thesis has been divided in two parts that deal with problems of different nature. The first part is titled Design Rules and Actuator Modeling for the Optimization of Mechatronic Systems and focuses on providing the detailed analysis of different actuators using a general procedure and oriented towards improving the actuator design. It introduces a new methodology to analyze linear electromagnetical and hydraulic actuators by modeling their maximum output mechanical quantities (force, work and stroke) as functions of the geometry and material properties and discusses the scalability (in the sense of producing the same stress and strain distribution for different sizes). The motivation to undertake such a work stems from the need for light and volume reduced structures and systems, which are to be integrated in the design procedure as early as possible. Hence, the geometric relationships, aspect ratios and material properties that maximize the actuator output quantities with a certain limited volume or weight, along with their scalability for the integration in structures are studied. A validation of the results is done by performing dimensional analysis of the expressions obtained and comparing numerical results with industrial actuator data. The static behavior of different classes of actuators is considered. Such actuators include linear hydraulic and electromagnetic actuators. The second part is titled Identification and Control of Piezoelectric Actuators}. Piezoelectric actuators are proving to be a reliable solution for many engineering applications, ranging from micro-positioning (machine tools, optic devices or modern microscopes) to active control of structures. The main motivation of this thesis part is to delve into models to represent the hystereticbehavior of piezoelectric actuators in order to apply them to the conception of controllers for such hysteretic systems. A general study of piezoelectric actuators is performed to later deal with the modeling of such actuators. Due to the high non-linear behavior observed, the problem of identifying and modeling the actuator requires a hysteresis model. The Bouc-Wen model has been chosen and investigations to identify its parameters and to validate the model have been undertaken. Once the system has been identified, a linear controller has been designed and implemented in a real platform, employing a DSP (Digital Signal Processor). Although the two parts are clearly differentiated, the thesis unity can be found in the roots of Mechatronics. The thesis deals with the response to one single question: How can we improve a mechatronic system? However, the answer is twofold: By designing and modeling optimum actuators taking into account the whole system or structure and by controlling the system appropriately using developed models.Postprint (published version

Design of the Annular Suspension and Pointing System (ASPS) (including design addendum)

The Annular Suspension and Pointing System is an experiment pointing mount designed for extremely precise 3 axis orientation of shuttle experiments. It utilizes actively controlled magnetic bearing to provide noncontacting vernier pointing and translational isolation of the experiment. The design of the system is presented and analyzed