This paper discusses the design and implementation of a high performance, custom control solution for series elastic actuators (SEA) in a parallel or serial configuration. In many modern robotics applications, controlling actuator output force accurately and with high bandwidth is extremely important. The series elastic actuator has become popular in applications which require precise force control, however currently not many commercial options exist. Commonly, these actuators are custom designed and use electric motors, however most off-the-shelf electric motor drives are not designed for this specific application. In this paper, the hardware and software architecture of a control device designed specifically for force controlled series elastic actuators is described, along with test results on a novel SEA design. / Master of Science

Hardware Acceleration is the most sought technique in chip design to achieve better performance and power efficiency for critical functions that may be in-efficiently handled from traditional OS/software. As technology started advancing with 7nm products already in the market which can provide better power and performance consuming low area, the latency-critical functions that were handled by software traditionally now started moving as acceleration units in the chip. This thesis describes the accelerator architecture, implementation, and prototype for one of such functions namely "Locality-Aware memory compression" which is part of the "OS-controlled memory compression" scheme that has been actively deployed in today's OSes. In brief, OS-controlled memory compression is a new memory management feature that transparently, dramatically, and adaptively increases effective main memory capacity on-demand as software-level memory usage increases beyond physical memory system capacity. OS-controlled memory compression has been adopted across almost all OSes (e.g., Linux, Windows, macOS, AIX) and almost all classes of computing systems (e.g., smartphones, PCs, data centers, and cloud). The OS-controlled memory compression scheme is Locality Aware. But still under OS-controlled memory compression today, applications experience long-latency page faults when accessing compressed memory. To solve this per- performance bottle-neck, acceleration technique has been proposed to manage "Locality Aware Memory compression" within hardware thereby enabling applications to access their OS- compressed memory directly. This Accelerator is referred to as HALK throughout this work, which stands for "Hardware-accelerated Locality-aware Memory Compression". The literal mean- ing of the word HALK in English is 'a hidden place'. As such, this accelerator is neither exposed to the OS nor to the running applications. It is hidden entirely in the memory con- troller hardware and incurs minimal hardware cost. This thesis work explores developing FPGA design prototype and gives the proof of concept for the functionality of HALK by running non-trivial micro-benchmarks. This work also provides and analyses power, performance, and area of HALK for ASIC designs (at technology node of 7nm) and selected FPGA Prototype design. / Master of Science / Memory capacity has become a scarce resource across many digital computing systems spanning from smartphones to large-scale cloud systems. The slowing improvement of memory capacity per dollar further worsens this problem. To address this, almost all industry-standard OSes like Linux, Windows, macOS, etc implement Memory compression to store more data in the same space. This is handled with software in today's systems which is very inefficient and suffers long latency thus degrading the user responsiveness. Hardware is always faster in performing computations compared to software. So, a solution that is implemented in hardware with the low area and low cost is always preferred as it can provide better performance and power efficiency. In the hardware world, such modules that perform specifically targeted software functions are called accelerators. This thesis shows the work on developing such a hardware accelerator to handle ``Locality Aware Memory Compression" so as to allow the applications to directly access compressed data without OS intervention thereby improving the overall performance of the system. The proposed accelerator is locality aware which means least recently allocated uncompressed page would be picked for compression to free up more space on-demand and most recently allocated page is put into an uncompressed format.

Direct fault testing onboard Dynamic Position Vessels is a requirement to maintain the ships classification and ensure redundancy of the power system onboard to maintain position. The most vulnerable part of the ship when testing occurs is when a three phase fault is placed on a main bus. This puts tremendous amount of strain on the system. This thesis offers an alternate and safer way to ensure the protection equipment is working properly by using a fault signal using from Programmable Logic Controller in conjunction with the protection relays. A working PSCAD model of Transocean's DEEPWATER CHAMPION was developed using a one line diagram. Using the developed PSCAD model three phase fault currents could be calculated and then simulated as a scaled down secondary current to use for testing the protection relays. To test the develop testing system different bus configurations were analyzed to determine loss of thruster capabilities which deter the vessel to maintain position. / Master of Science

The principle of braking in road vehicles involves the conversion of kinetic energy into heat. This high energy conversion therefore demands an appropriate rate of heat dissipation if a reasonable temperature and performance stability are to be maintained. While the design, construction, and location features severely limit the heat dissipation function of the friction brake, electromagnetic brakes work in a relatively cool condition and avoid problems that friction brakes face by using a totally different working principle and installation location. By using the electromagnetic brake as supplementary retardation equipment, the friction brakes can be used less frequently and therefore practically never reach high temperatures. The brake linings thus have a longer life span, and the potential "brake fade" problem can be avoided. It is apparent that the electromagnetic brake is an essential complement to the safe braking of heavy vehicles. In this thesis, a new mathematical model for electromagnetic brakes is proposed to describe their static characteristics (angular speed versus brake torque). The performance of the new mathematical model is better than the other three models available in the literature in a least-square sense. Compared with old models that treat reluctance as a constant, our model treats reluctance as a function of speed. In this way, the model represents more precisely the aggregate effect of all side effects such as degree of saturation of the iron in the magnet, demagnetizing effects, and air gap. The software program written in Matlab can be used to code different brake characteristics (both static and dynamic) and evaluate their performance in different road scenarios. A controller is designed that achieves wheel-slip control for vehicle motion. The objective of this brake control system is to keep the wheel slip at an ideal value so that the tire can still generate lateral and steering forces as well as shorter stopping distances. In order to control the wheel slip, vehicle system dynamic equations are given in terms of wheel slip. The system shows the nonlinearities and uncertainties. Hence, a nonlinear control strategy based on sliding mode, which is a standard approach to tackle the parametric and modeling uncertainties of a nonlinear system, is chosen for slip control. Due to its robustness properties, the sliding mode controller can solve two major difficulties involved in the design of a braking control algorithm: 1) the vehicle system is highly nonlinear with time-varying parameters and uncertainties; 2) the performance of the system depends strongly on the knowledge of the tire/road surface condition. A nominal vehicle system model is simulated in software and a sliding mode controller is designed to maintain the wheel slip at a given value. The brake control system has desired performance in the simulation. It can be proven from this study that the electromagnetic brake is effective supplementary retardation equipment. The application and control of electromagnetic brakes might be integrated with the design of vehicles and their friction braking systems so that an ideal match of the complementary benefits of both systems might be obtained to increase safety to a maximum while reducing vehicle operating costs to a minimum. / Master of Science

A hard chromium electroplating process is normally used for preventing mechanical and electrical parts such as roller, piston and mold from the harmful environments and giving the good physical properties on the surface such as increased wear resistance, increased hardness, low frictional coefficient as well as good aesthetic look on the surface of workpieces. The problem that often found in this process is the deflected workpieces after plating process due to the low plating performance during a plating period. These deflected workpieces are needed to replating it again. However, the replating method causes a large amount of resource consumptions and increases the production time. To handle this problem, the plating solution temperature is needed to maintain the plating solution temperature at a set point about 50 °C in order to improve the plating performance during the plating period and decrease the occurrence of the deflected workpieces. In this work, the mathematical models are developed to explain the dynamic behavior of the plating solution temperature during the plating time and validated with the real data from a plant. The conventional (PID) controller is applied to this process for the purpose of keeping the plating solution temperature at the set point throughout the plating time. The result demonstrates that the developed mathematical models can be used to explain the dynamic behavior of the plating solution temperature because it gives the good simulation of the plating solution temperature with a slightly different from the real data. Furthermore, the PID controller shows the high control performance for maintaining the plating solution temperature at the set point throughout the plating period with small overshoot at the beginning of every batch.

Sammanfattning Kandidatuppsats i företagsekonomi Ekonomihögskolan, Linnéuniversitetet VT 16 Författare: Viktor Odenbrink, Louis Perikala, Viktor Johansson Handledare: Tom Karlsson Titel: Controllerrollen inom den offentliga sektorn Bakgrund och problem: Det existerar många studier om controllerrollen inom den privata sektorn, studier inom den privata sektorn belyser också vilka arbetsuppgifter och egenskaper som är relevanta för en controller. Däremot råder det delade meningar om controllerrollen inom den offentliga sektorn, vissa studier säger att rollen skiljer sig åt och andra forskare skriver att rollen är densamma inom båda sektorer. Vi vill med denna studie belysa vad det innebär att vara controller inom den offentliga sektorn och vilka arbetsuppgifter och egenskaper som är relevanta för rollen. Syfte: Syftet med denna studie är att beskriva vad det innebär att vara en controller inom den offentliga sektorn och vilka arbetsuppgifter och egenskaper som är av vikt. Detta för att skapa mer kunskap om den offentliga controllerrollen. Metod: En kvalitativ forskningsansats har legat till grund för studien. Forskningen ses som en kvalitativ intervjustudie. Empirin har inhämtats genom semistrukturerade intervjuer med controllers samt med ekonomer med arbetsuppgifter likt en controller inom den offentliga sektorn. Slutsats: Den stora skillnaden i vad det innebär att vara controller inom den offentliga och privata sektorn är att en controller inom den offentliga sektorn betonar vikten av att få vara med och bidra till välfärd och samhällsnytta. Arbetsuppgifterna och egenskaperna är svåra att placera in i en specifik controllerroll och det rör sig snarare mot en hybridroll, där controllern bör ha inslag från kamrerrollen, den analytiska rollen, pedagogiska rollen och coachrollen. Nyckelord: Offentliga sektorn, controller, arbetsuppgifter, egenskaper / Abstract Bachelor Thesis in Business Administration School of Business and Economics, Linnaeus University, Växjö 2016 Authors: Viktor Odenbrink, Louis Perikala, Viktor Johansson Supervisor: Tom Karlsson Title: The role of a controller within the public sector Background: There are many studies on the role of controllers within the private sector, studies in the private sector focus on the work assignments and characteristics that are relevant for a controller as well. However, there are different opinions and interpretations regarding the role of controller in the public sector, some studies say that the roles differs while other researchers state that the roles are similar in both sectors. Our goal with this study is to shed light on what it means to be a controller within the public sector and the work assignments and characteristics that are relevant to the role. Purpose: The purpose of this study is to describe what it means to be a controller within the public sector and the work assignments and characteristics that are of importance. This is to create more knowledge about the role of a controller within the public sector. Method: A qualitative research approach has been the basis for this study. The research is seen as a qualitative interview. The empirical data has been collected through semi-structured interviews with controllers and economists with similar duties as a controller within the public sector. Conclusion: The big difference in what it means to be a controller within the public and private sector is that a controller within the public sector emphasizes the need to be involved in the contribution to the welfare and social benefits. The work assignments and characteristics are difficult to place in a specific segment and this points towards a so called hybrid role, which means that the controller should have elements from all the segments which include the role of an accountant, the analytical role, the pedagogical role and lastly the so called coaching role. Keywords: Public sector, controller, work assignments, characteristics

Empresas e instituições de pesquisa nacionais e internacionais tem concentrado esforços no sentido de desenvolver e promover a implementação do padrão internacional ISO 11783, baseado no protocolo de comunicação digital CAN (Contoller Network Area), para integração de dispositivos em máquinas e implementos agrícolas. Nesse contexto, é apresentado o desenvolvimento e a aplicação de um modelo baseado no formalismo das redes de Petri como uma ferramenta de suporte para a análise e implantação de uma rede CAN em aplicações com tempos-críticos. O modelo foi elaborado no ambiente para edição e simulação DesignCPN, sendo que a simulação é utilizada para a análise do desempenho e do comportamento de uma rede CAN com diferentes configurações que será embarcada em um veículo autônomo agrícola (VAA). / Intemational and national research institutions and companies have focused efforts to develop and promote the implementation of the international standard ISO 11783, based upon the digital communication protocol CAN (Controller Area Network), in order to integrate devices in machines and agricultural implements. Therefore, it is presented the development and the application of a model based on Petri nets\' formalism as a tool for the support, analysis and accomplishment of a CAN bus in time-critical applications. The model was constructed in an environrnent for edition and sirnulation of colored Petri nets, the software DesignCPN. The sirnulation was used for the analysis of the behavior and the performance the CAN bus for several configurations, which will be embedded in an Autonomous Agricultural Vehicle (VAA).

Estuda-se o problema de sintonia de controladores, objetivando-se a formulação do problema de sintonia ótima de controladores. Busca-se uma formulação que seja geral, ou seja, válida para qualquer estrutura de controlador e qualquer conjunto de especificações. São abordados dois temas principais: especificação de controladores e sintonia ótima de controladores. São compiladas as principais formas de especificação e avaliação de controladores e é feita a formulação do problema de sintonia de controladores como um problema padrão de otimização. A abordagem proposta e os conceitos apresentados são então aplicados em um conjunto de exemplos. / The problem of control tuning is studied, aiming the formulation of the optimal control tuning problem. A general formulation, valid for any controller structure and any set of specifications, is sought. Two main themes are addressed: controller specification and optimal controller tuning. The main ways of controller specification and assessment are compiled and the optimal controller tuning problem is formulated as a standard optimization problem. The proposed approach and the presented concepts are then applied in a set of examples.

Made available in DSpace on 2016-04-25T18:40:15Z (GMT). No. of bitstreams: 1 Elaine Rosa de Oliveira.pdf: 4397139 bytes, checksum: 0db0de60d5d717606e102bd709175625 (MD5) Previous issue date: 2015-12-18 / At present, the market requires a professional ready to take on new responsibilities. Such a reality also makes it necessary that he/she continuously develop more skills and qualifications. Then, a question emerges as to whether colleges can catch up with such constant dynamism in their subject curriculum in order to equip students with adequate training that would make them critical and able to guide the administration so as to keep business along the planned route. This investigation presents a critical analysis of the Controller education. The research aimed to learn how the training of this professional takes place so he/she can fill this position. Through bibliographical research, it was identified the profile of higher education in Controlling in Brazil, the performance of the Controller in the Controller s office and skills recognized as necessary to this professional. Data were collected regarding the curricula of three institutions of higher education in Accounting, considered the best in the job market, and which disclose their curriculum. They are UFMG, USP and Mackenzie. The content of these curricula was confronted with the skills, deemed, in the literature, as the ones desired from a Controller. Comparison of these two sources revealed that a relevant part of the attributes that the Controller must possess is not addressed in the subjects of higher education in Accounting. The main deficiencies identified in the curricula were disciplines that approach behavioral development. Thus, a proposal to improve the training of professionals has been outlined. It was appointed that search for coaching and, if possible, mentoring is necessary since it was understood that if behavior should be changed, it must take place beyond the professional life. Finally, some suggestions are made for additional training for those who wish to successfully fill the Controller position, so as to improve their technical and behavioral skills / Nos dias de hoje, a realidade do mercado exige um profissional pronto para assumir novas responsabilidades o que progressivamente exige também mais competências e qualificações de seus profissionais. Muitas vezes questiona-se se as faculdades possuem o mesmo dinamismo de atualização em seu programa de disciplinas para formar profissionais com bagagem de conhecimento suficiente para serem críticos e capazes de nortear a administração a fim de manter o negócio na rota prevista. O presente trabalho apresenta uma análise crítica da formação do profissional Controller e uma pesquisa que objetivou conhecer, como ocorre a formação do profissional para ocupar esta posição. Por meio de pesquisa bibliográfica, apresentou-se uma abordagem do ensino superior de Contabilidade no Brasil, a atuação do Controller na controladoria e as competências apontadas na pesquisa como necessárias a este profissional. Foram levantados dados referentes às grades curriculares das três instituições de ensino superior em Contabilidade, mais bem avaliadas pelo mercado de trabalho e que divulgam sua grade curricular, que foram as UFMG, USP e Mackenzie; o conteúdo destas grades foi confrontado com as competências obtidas na pesquisa bibliográfica acerca do que cabe ao Controller. O confronto dessas duas fontes apontou que uma parte relevante dos atributos que o Controller deve possuir não é abordada no curso de graduação de Contabilidade por estas instituições, enquanto conteúdo. As principais carências constatadas nas grades curriculares foram de disciplinas que propusessem o desenvolvimento comportamental, e, neste foco, como proposta de melhoria na formação dos profissionais, foi indicada a busca por coaching e se possível, mentoring, pois, entendeu-se que o comportamento, para ser mudado, precisa ocorrer além do aspecto profissional. Ao final são apresentadas algumas sugestões de formação complementar para suprimento das carências de competências técnicas e comportamentais, para aqueles que desejarem ocupar a posição Controller

Empresas e instituições de pesquisa nacionais e internacionais tem concentrado esforços no sentido de desenvolver e promover a implementação do padrão internacional ISO 11783, baseado no protocolo de comunicação digital CAN (Contoller Network Area), para integração de dispositivos em máquinas e implementos agrícolas. Nesse contexto, é apresentado o desenvolvimento e a aplicação de um modelo baseado no formalismo das redes de Petri como uma ferramenta de suporte para a análise e implantação de uma rede CAN em aplicações com tempos-críticos. O modelo foi elaborado no ambiente para edição e simulação DesignCPN, sendo que a simulação é utilizada para a análise do desempenho e do comportamento de uma rede CAN com diferentes configurações que será embarcada em um veículo autônomo agrícola (VAA). / Intemational and national research institutions and companies have focused efforts to develop and promote the implementation of the international standard ISO 11783, based upon the digital communication protocol CAN (Controller Area Network), in order to integrate devices in machines and agricultural implements. Therefore, it is presented the development and the application of a model based on Petri nets\' formalism as a tool for the support, analysis and accomplishment of a CAN bus in time-critical applications. The model was constructed in an environrnent for edition and sirnulation of colored Petri nets, the software DesignCPN. The sirnulation was used for the analysis of the behavior and the performance the CAN bus for several configurations, which will be embedded in an Autonomous Agricultural Vehicle (VAA).