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In the face of rapid development in information technology coupled with a growing dynamism in global markets, new concepts of building computer controlled machines have proliferated. Such approaches promise to lead to a new generation of machines which typically share common design objectives. They seek to advance the underlying concepts of contemporary computer controlled machines (such as robots, CNC, etc.) in a way that resultant systems demonstrate attributes of flexibility, extendibility, configurability, openness, modularity and so on.

This thesis is concerned with sequence logic as found in industrial control systems, with the focus being on process and manufacturing control systems. At its core is the assertion that there is a need for a better approach to the development of industrial sequence logic to satisfy the life-cycle requirements, and that many of the ingredients required to deliver such an approach are now available. The needs are discussed by considering the business case for automation and deficiencies with traditional approaches. A set of requirements is then derived for an integrated development environment to address the business needs throughout the control system life-cycle. The strengths and weaknesses of relevant control system technology and standards are reviewed and their bias towards implementation described. Mathematical models, graphical methods and software tools are then assessed with respect to the requirements for an integrated development environment. A solution to the requirements, called Synect is then introduced. Synect combines a methodology using familiar graphical notations with Petri net modelling supported by a set of software tools. Its key features are justified with reference to the requirements. A set of case studies forms the basis of an evaluation against business needs by comparing the Synect methodology with current approaches. The industrial relevance and exploitation are then briefly described. The thesis ends with a review of the key conclusions along with contributions to knowledge and suggestions for further research.

Brushless permanent magnet (PM) drive systems offer a high efficiency over a wide power/torque-speed operating envelope, however, there are a number of problems that may limit, or complicate, their operation particularly in automotive and aerospace vehicular applications, i.e. the loss of control of the power silicon gate drive circuitry during fluxweakening operation, control of high-speed low-inductance machines and the presence of large electrolytic capacitors on the inverter DC link. Current Source Inverters (CSIs) could potentially address some or all of the above issues. However, they have found little application to date due to the wide use of the Voltage Source Inverter (VSI) circuit topology.This thesis investigates feasibility of utilising Current Source Inverters (CSIs) to control permanent magnet synchronous machines in automotive and aerospace actuation systems. CSIs, switching at the fundamental frequency, were used in some of the first semiconductor based, electronic variable speed drive systems that utilised the simple, low maintenance AC induction motor. However, the rapid progress of semiconductors and discovery of Pulse Width Modulation (PWM) techniques soon resulted in the Voltage Source Inverter (VSI) replacing the CSI in all but the highest power applications. Modern power electronics and (micro-processor based) control systems mean that the advantages of VSI systems may no longer be significant and combined with the unique environmental conditions that automotive and aerospace applications present, could allow the CSI to offer advantages over VSIs in these applications.The thesis presents the switching and control logic for CSIs and mapping to the more conventional VSI logic. Analysis is made of the various loss mechanisms in VSI and CSI power circuitary. Simulation models of the VSI and CSI structures are presented and representative drive systems designed, built and tested to validate the model developed. Comparisons are made of the two inverter topologies based on power conversions and loss audits of the test validation hardware.

Produktiviteten inom byggbranschen har länge ansetts som låg och byggbolag i sektorn arbetar för att bli effektivare. Denna rapport syftar till att utreda hur informationsflödet vid grundläggning av betongpålar kan effektiviseras. Studien utgår ifrån Skanska Sverige ABs region Skanska Grundläggning som bland annat bedriver betongpålningsverksamheten inom företaget. För att skapa en förståelse för informationsflödet inom verksamheten behövde författarna kartlägga de befintliga arbetssätten som används idag. Målsättningen var sedan att utifrån det nuvarande tillståndet formulera ett framtida tillstånd med en ökad effektivitet i informationsflödet. Inom byggsektorn implementeras BIM på bred front och detta arbetssätt utreds i rapporten som en möjlighet till ett förbättrat informationsflöde.  För att kartlägga betongpålningsproduktionen inom företaget har metoden värdeflödesanalys använts. Metoden är ett sätt att kartlägga en specifik process, där produkten som kunden vill ha följs. Analysen har sitt ursprung från Toyotas arbetssätt som idag benämns som lean.  Kartläggningen av betongpålning i rapporten hade sin start vid transport från fabrik och slut vid när pålen lämnats över till kunden. I kartläggningen följer författarna materialflödet samt informationsflödet knutet till materialet under förädlingsprocessen. Insamlingen av data till kartläggningen gjordes genom en intervjustudie och en observationsstudie. För att förstå möjligheten till implementeringar utfördes även en enkätstudie och intervjustudie, angående utnyttjandet av BIM inom Skanska Grundläggning. Användningen av BIM inom organisationen skiljde sig mellan de olika yrkesgrupperna, tjänstemän och yrkesarbetare. Enkätstudien utfördes på fem projekt i Stockholmsområdet. Bland tjänstemännen arbetade 8 av 19 med BIM varje vecka eller oftare medan 16 av 17 yrkesarbetare aldrig arbetat med BIM. Resultaten till värdeflödesanalysen var hämtade från två projekt, FSE 105 Betongtunnel Kungens kurva och Trafikplats Vega. Utifrån resultaten formulerades två förbättringsområden, där utsättning genom maskinstyrning var det ena och digitalisering av dokumentation var det andra. Implementeringen av GPS-styrning på pålkranar behöver inte lång tid för att löna sig ekonomiskt. Utifrån resultaten kan ca 170,000 SEK sparas per år och maskin om maskinstyrning implementeras, samt att det finns ytterligare positiva effekter som framkommit men inte uppmäts i denna studie. Det finns dock hinder i användarvänligheten och tekniken kräver idag manuell handpåläggning i vissa moment. För utvecklingen av BIM hos medarbetarna finns stora vinster genom förenklade informationsflöden men också svårigheter eftersom en stor del av medarbetarna idag blir hindrade av tekniken. / Productivity in the construction industry has for a long time been considered as low compared to other industries. The construction industry has started to adapt strategies that have been successful in other industries to increase the productivity. This report aims to examine how the information flow during foundation of concrete piles can be more efficient. The study is based on Skanska Sweden AB for the region of Skanska foundation. Concrete piling is one of the foundation activities that Skanska foundation performs. To create an understanding about the information flow, the authors had to identify the existing working method that was used today. The aim was then based on the current state to formulate a future state with a greater efficiency in the flow of information. BIM has begun to be implemented as a working method in the construction sector and have therefore been investigated in the report as an opportunity for an improved flow of information. To identify the production process for concrete piling within the company the authors have used value stream mapping. The method is a way of mapping a specific process, where the product that the customer wants is followed. The analysis originating from Toyotas method which today is referred to as lean. The mapping of concrete piling started from the transport of the factory to the pile was handed over to the customer. During the mapping the authors follows the material flow and the information flow related to the material during the process. The collection of data for the value stream mapping was done based on interviews and observations. To understand the possibility of implementations carried out a questionnaire and interviews, regarding the use of BIM in Skanska foundation. The use of BIM within the organization differs between the different professional groups, civil servants and skilled workers. The questionnaire survey was conducted on five projects in the Stockholm area. Among civil servants eight of 19 worked with BIM weekly or more often, while 16 of 17 skilled workers never had worked with BIM at all. The results of value stream analysis were collected from the two projects, the FSE 105 Concrete tunnel at Kungens kurva and interchange Vega. Based on the results the authors have formulated two areas of improvements. The first improvement is about release measuring through machine control and the second are about digitization of documents. Implementation of machine control on a pile driver does not need a long time to pay off financially. From the results, about 170,000 SEK can be saved per year and machine if machine control would be implemented on the pile drivers. There are more positive effects that have been observed during the study but these effects have not been measured.  However, there are obstacles in the usability and technology today that require manual intervention at certain stages. For the development of BIM among the employees there are great gains through simplified information flow. With that there comes difficulties since a large proportion of employees is hindered by technology.

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his master thesis deals with application of measuring probes in machining process. There is indicated a brief overview of the measurement methods used in cutting operation. It is also focused on the measurements of using probes to verify the acceleration and refinement of the production.

Master´s thesis describes surveying during asphalt paving at the airport in Arvidsjaur, Sweden. The thesis focuses especially on machine control and its practical usage. It describes particular methods of machine control and analyses in detail machine control for asphalt pavers.

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This work deals with the creation of a mathematical model of load workplace for rotating electrical machines. The first part provides a general description of servomotors and their mathematical equations. The second part describes the commissioning and connection of the PLC to the inverter and the subsequent creation of PLC programs. The last part describes the creation of the PMSM model with its control and then verified the validity of the model and the real machine.