The use of low-power wireless sensors and actuators with networking support in in-dustry has increased over the past decade. New generations of microcontrollers, new hardware for communication, and the use of standardized protocols such as the Internet Protocol have resulted in more possibilities for interoperability than ever before. This in-creasing interoperability allows sensors and actuator nodes to exchange information with large numbers of peers, which is beneficial for creating advanced, flexible and reusable systems.The increase in interoperability has resulted in an increase in the number of possible attacks from malicious devices or users. For this reason, the use of encryption techniques to protect client and server communications has become mandatory. However, even with state-of-the-art encryption mechanisms, there is no protection that can control access to each particular service with fine-grained precision. The nodes within an industrial network of wireless sensors and actuators are resource-constrained embedded devices, and increasing interoperability therefore requires a higher level of computation capabil-ities. The nodes’ intrinsic limitations of memory and processing exert an adverse effect on power consumption and communication delays, resulting in a shorter battery life-time. Therefore, the standard computing solutions for Internet communications are not directly applicable, and new mechanisms to achieve security, scalability, dependability, interoperability and energy efficiency are needed.Sensor and actuator networks can transmit sensed data, but they also offer access to the actuators. Such accesses, presumably provided via services, require an access protection scheme. For this reason, the use of access control mechanisms is mandatory. Access control assists in the creation of customized services and access policies. These access policies can isolate access permissions to devices with different roles, such as production and maintenance.The main contribution of this thesis is a novel, efficient IoT framework for industrial applications, including design, implementation, and experimental validation. The frame-work includes features for communication protection, authentication, fine-grained access control, zero-configuration networking, and run-time reconfiguration. These technologies and their corresponding energy consumption data clearly demonstrate the feasibility of integrating a battery-operated IoT concept into a functional System of Systems. The provided data also pinpoint the most critical areas for improvement.

The Industrial Internet of Things (IIoT) is the result of the intersection between advancements in technology and the demand for more efficient and sustainable industry. Technology has provided a means for a large and heterogeneous collection of networks, devices, developers, owners, users and other stakeholders. From this there is a clear need for highly interoperable and independently developed systems. Interoperability is a communication challenge which affects all layers in a system. Communication protocols such as HTTP, CoAP, XMPP, OPC-UA and MQTT are above the network layer and below a semantic layer. This challenge includes overcoming interaction pattern differences, such as session and session-less protocols or publish/subscribe and request/response protocols. Common interoperability methods look at utilizing, a) middleware, such as in-system adapters and protocol gateways or b) restricting protocols to one or two possibilities. However, these solutions do not fit IIoT well as they are costly to adapt as the protocol landscape evolves, are intrusive to design or increase development costs. Service-Oriented Architecture (SOA) has been identified as having a great potential for integrating independent systems. When applied to industrial contexts, SOA late-binding and service composition offers opportunities for enhancing interoperability. However, SOA-based service contracts still require complete agreement between provider and consumer in order to exchange service. In this thesis an approach toward interoperability is proposed which leverages SOA principles and a multi-protocol translator. The proposed approach is first contextualized with a set of requirements pulled from existing literature and from application domain requirements. The thesis asks the question; how can late-binding and service composition be used to support a multi-protocol network of systems? The result, a new approach of a secure, on-demand and transparent protocol translator, is proposed. Conceptually satisfying the requirements defined, the design is backed up with empirical testing on usability and latency of the solution. The proposed solution differs from middleware in that, it is a participant (alongside the application system), it is on-demand (only used when needed), it is not intrusive (no design time dependencies) and it operates transparently (to application systems). A complete interoperability solution is deemed as future work, which could extend to full security, general encoding and semantic interoperability.

The conducting winding of an electrical machine is insulated in order to prevent any short circuits to occur within the machine. This insulation is during its lifetime exposed to several environmental stresses and therefore plays an important role in the life length of the machine. Accelerated stress tests are used to investigate what design and material is most suitable for a good endurance of a product. In this master thesis, new accelerated test methods for the insulation system in an electrical machine are developed and evaluated. The study resulted in four stress tests that simulate the thermal stress, the thermomechanical stress and the ambient stress from direct oil cooling. Three diagnosis tests and a material analysis were used in order to evaluate how these accelerated stress test methods affected the insulation. The diagnosis tests showed no clear sign of deterioration of the insulation in terms of change in electrical characteristics. However, the material analysis indicated deterioration of the insulation, such as cracks and oxidation of the material. These changes show that the test methods are capable to affect the insulation, but will need more time to cause a breakdown, since a stator of this kind is expected to have a very long life length. Therefore, in future work on this topic, these test methods should continue for a longer time and it would likely be interesting to look into other diagnosis tests.

This project is about developing a complete amplifier that can integrate with three differentclass-D amplifier modules. With the thought so that the product can later be sold on themarket.Where the use of the product can be used for either home or cinema audio systems.We have designed and reused existing schematic solutions and the company has assisted indeveloping some of the schematics. The result of this report is the development and design ofcircuit boards with EMC guidelines.

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The aim of this project is to acquire gas data using an Arduino microcontroller. This project is part of a bigger project called The electronic nose where mechanical, thermal, electrical, electronic and software parts work together. It is the continuation of a project handled before where mainly the mechanical, thermal and electrical parts were done.   The whole e-Nose project is divided in 4 main subcategories: general mechanical structure, thermal and piston electric circuit, gas sensors and software. My work will be focused in the last two subcategories of the general project.   The sample to be measured is placed inside of a moving cylinder, which will lift up the sample reaching near the sensors and warming it using a thermal resistance, to release more odor. That is where the sensors act, synchronized with the piston, will get the data through the Arduino and sends it to the computer to be analysed. The sensors will be activated using an Arduino Mega 2560 and transferred to the computer to be analysed with MatLab.   To control the measurement, a push button, a LCD display and a LED will be placed; having like this a full control of the project and an easy interface for the user. Six gas sensors will be used, which will be enough to be able to differentiate between different kind of gases. With such variety it is possible to categorize between combustible gas (methane, propane, LPG etc.), NH3, alcohol and more gases.   The e-Nose will be able to measure different gases in more than ways depending on the program we choose. For a more accurate response, more sensors would be needed using a sensor fusion method or more accurate sensors.

This thesis presents contributions in the field of satellite navigation with a focus on array processing and related implementation issues. For readers not familiar with GNSS, it also includes a brief overview of satellite navigation.Compared to the state of the art only ten years ago, modern GNSS receivers are very capable. One reason for this improvement is advances in the semiconductor industry that have increased both the available processing power and the energy efficiency. An active research community have also made important contributions resulting in more sophisticated algorithms. To improve receiver performance even further, auxiliary sensors such as gyros and accelerometers are becoming increasingly common. A related option involves using an antenna with several physical elements. This is known as an antenna array and is often used for radar, sonar and telecommunication applications. Array processing can also be used for GNSS and as such it is the primary focus of this thesis. An array allows for exploration of the spatial domain, in other words a receiver that may differentiate between signals depending on the direction of arrival. For GNSS, where interference and multipath (signal reflection off, for example, buildings or the ground) may be significant sources of error, this is an attractive solution. Although array processing have been the subject of extensive research efforts within other fields, there are several remaining issues with regards to how these techniques can be implemented in a GNSS receiver.With regards to array processing there are also properties unique to GNSS, such as multiple signal sources at known positions, that have not been explored sufficiently in previous efforts. In this thesis we show how these properties can be exploited to improve receiver performance in dynamic scenarios. In short, the orientation of the antenna platform is estimated accurately (typical variance around 1°) using beamforming techniques. This information is then used to achieve a better estimate of the radio environment by allowing for longer integration periods when estimating the covariance matrices. A better estimate of the covariance matrices directly translates into improved receiver performance, especially so in areas of moderate levels of multipath/interference.Further, a method to calibrate GNSS array antennas using real signals is investigated in detail. Instead of resorting to electromagnetic simulations that requires precise knowledge about the antenna and installation factors, or RF chamber measurement that is expensive, it is shown how the array antenna can be calibrated using live signals. The accuracy of the resulting model is verified using real data.Also, the first implementation of an RF record and replay system is presented. With such a system data can be recorded in a specific environment, generally a time consuming task, and later played back into the antenna input of any GNSS receiver. Such systems are nowadays commercially available and have proven very useful for testing and validation of GNSS receivers. Throughout the thesis, the required receiver architecture and practical viability of the proposed algorithms are considered. / Godkänd; 2011; 20110217 (staffan); DISPUTATION Opponent: Associate Professor Gonzalo Seco Granados, Universitat Autònoma de Barcelona, Barcelona, Spain Ordförande: Professor Dennis Akos, Institutionen för system- och rymdteknik, Luleå tekniska universitet Tid: Torsdag den 7 april 2011, kl 13.00 Plats: A117, Luleå tekniska universitet

This thesis presents the foundations of a method for estimating fibre properties of pulp suitable for online application in the pulp and paper industry. In the pulp and paper industry, increased efficiency and greater paper quality control are two of the industry's main objectives. It is proposed that online fibre property measurements are a means of achieving progress in both of these objectives. Optical based systems that provide valuable geometric data on the fibres and other pulp characteristics are commercially available. However, measurements of the elastic properties of the fibres are not currently implemented using these systems. To fill this gap an ultrasound based system for measuring the elastic properties of the wood fibres in pulp is proposed. Ultrasound propagation depends on the elastic properties of a solid. Hence attenuation measurements from suspensions of fibres depend on their elastic properties. The method is based on solving the inverse problem where the output is known and the objective is to establish the inputs. In this case, attenuation is measured and a model of attenuation based on ultrasound scattering is developed. A search algorithm is used for finding elastic properties that minimize the error between the model and measured attenuation. The results of the search are estimates of the elastic properties of the fibres in suspension. The results show resonance peaks in the attenuation, in the frequency region tested, for fibres with radii of the order of 10 microns. These peaks are found in both the measured and modelled attenuation spectra. Further investigation of these resonances suggests that they are due to modes of vibration in the fibre where the fibre modelled as an infinitely long cylinder. These resonances are shown to aid in the identification of the elastic properties. The attenuation is found to depend heavily on the geometry of the fibres. Hence fibre geometry, which can be obtained from online optical fibre measurement system, provides the key to extracting the elastic properties from the attenuation signal. Studies are also carried out on the effect of viscosity on attenuation as well as the differences in attenuation between hollow and solid synthetic fibres in suspensions. The measurement method is also applied to hardwood and softwood Kraft pulps. The results of these studies show that using the model derived in the thesis and attenuation measurements, estimates of the elastic properties can be obtained. The elastic property estimates for synthetic fibres agree well with values from other methods. The elastic property estimates for pulps require further validation due to the difficulty in comparing between different testing methods and different types of pulp. The conclusions, based on the work so far and under three realisable conditions, are that the shear modulus and the transverse Young's modulus of pulp fibres can be measured. Once these conditions are met a system based on this method can be implemented. By doing this the industry would benefit from the increase in paper quality control and energy saving such system could provide. / Godkänd; 2009; 20090507 (aitomaki); DISPUTATION Ämnesområde: Industriell elektronik/Industrial Electronics Opponent: Professor Richard Challis, the University of Nottingham, United Kingdom Ordförande: Teknologie doktor Torbjörn Löfqvist, Luleå tekniska universitet Tid: Onsdag den 3 juni 2009, kl 10.00 Plats: D770, Luleå tekniska universitet