Lamina emergent mechanisms (LEMs) can provide a way to meet the demand for more compact and inexpensive mechanisms. Previous research has developed LEM designs and identified applications for them, but many applications would benefit from suitable actuation techniques. This thesis presents the design considerations and a variety of applicable methods for internal and external LEM actuation in the macro scale. Integrated LEM actuator possibilities have been identified, each with its advantages and disadvantages depending on the application. Shape memory alloys are especially compatible with LEMs. Traditional actuators have also been discussed as a way of actuating a LEM from the outside for cases in which space constraints allow it. The feasibility of new internal actuators using basic actuation principles, especially flat solenoids, has been explored. The magnetic field distribution along the axis of a high-aspect-ratio solenoid has been derived. Analytical and experimental results show that the output force of a high-aspect-ratio solenoid is suitable for LEMs. A pseudo-solenoid conceptual prototype was manufactured and evaluated, revealing challenges for which solutions have been recommended.

Lignocellulosic biomass represents the largest potential volume and lowest cost for biofuel and biochemical production. Harnessing the full potential of the lignocellulosic biomass for low-carbon energy requires the knowledge of efficient breakdown and fractionation of its carbohydrates and lignin. Organic solvent pretreatment is recognized as an emerging way ahead because of its inherent advantages, such as the ability to fractionate lignocellulosic biomass into cellulose, lignin, and hemicellulose components with high purity, as well as easy solvent recovery and solvent reuse. Through all-atom MD simulation, we analyze the conformational transition of diverse lignin molecules in varying concentration of Methanol/water , DMSO/water mixtures and neat DMSO , neat methanol and water. From our work, it appears that in 40 mol% DMSO and 40 mol% methanol mixture (’theta solvent’) hardwood lignin(G/S=1.35) conforms random coil like structure, while 60 mol% DMSO and 60 mol% methanol solution (at 300 K) appears to be ’good solvent’ forhardwood lignin since it conforms extended chain like structure. While 80 mol% methanol is proven to be ’theta solvent’ and 80 mol% DMSO is proven to be ’good solvent’ for softwood lignin. We find that, major functional moieties of both lignin preferentially coordinated by methanol and DMSO molecules in increased organic solvents concentration which induces the conformational transition from crumbled globule to coil and prevent self-aggregation of lignin in binary mixtures. Chain dynamics of lignin explain the relaxation and subsequently elongated in addition of organic solvents into water.

Målet med detta arbete var att ta fram ett nytt trådmagasin till Sund Birstas α-kompaktor som är bättre ur ett säkerhets- samt ekonomiskt perspektiv. En kompaktor är en bindmaskin som komprimerar och binder samman valstrådrullar för att förhindra trassel samt underlätta förvararing och fraktning. Trådmagasinets huvudsakliga uppgift är att hålla kompaktorns bindtråd konstant sträckt för att förhindra att trassel uppstår bakom kompaktorn. Under arbetets konceptgenereringsfas togs delkoncept fram för ackumulering av tråd, lyftmekanismer samt förflyttningsmekanisker. Därefter togs 12 helhetskoncept fram som utvärderades först vid ett seminarium med Sund Birsta för att få värdefulla insikter kring koncepten. Därefter utvärderades koncepten med en Pughs-matris där koncepten jämfördes utifrån kriterier från Sund Birsta samt krav från kravspecifikationen. Det koncept som valdes ut från utvärderingen är en konstruktion som tillåter att användaren trär tråden igenom magasinet från golvnivå samt bidrar till en sänkning med 33% på kraften kompaktorns matarverk matar tråden med. En elmotor hjälper till att hålla tråden sträckt samt ladda magasinet genom att lyfta upp två rörliga brythjul. Det slutgiltiga konceptet utvecklades ytterligare för att kunna möjliggöra att allt arbete ska ske från golvnivå och därmed öka säkerheten. En CAD-modell togs slutligen fram för att illustrera konceptets utformning och funktion. / The goal of this project was to develop a new wire magazine for Sund Birsta´s α-compactor that is better from a safety and economical perspective. A coil compactor is a binding machine that compresses and binds together rod wire coils to prevent tangling and facilitate storage and transportation. The wire magazines main task is to keep the compactor’s binding wire constantly tense to prevent tangling from occuring behind the compactor. During the projects concept generation phase, subconcepts for lifting mechanisms, accumulation of wire and movement mechanisms was sketched. Thereafter 12 overall concepts was developed which was evaluated first at a seminar with Sund Birsta to gain valueble knowledge regarding the concepts. The concepts was thereafter evaluated with a Pughs-matrix where the concepts was compared with each other regarding to how well they met the demands set by Sund Birsta and from the requirements specification. The concept which was chosen from the evaluation is a construction which lets the user pull the wire through the magazine from ground level, and it lowers the force required for the compactor´s feeding unit with 33%. A electric motor helps keeping the wire tense and load the magazine by lifting up two movable wire wheels.

In the last decade, we have seen an increasing interest in the designing of interactive technology that is limited in energy usage to our bodily capabilities. This field is commonly referred to as Human-Power Interaction (HPI). The aim of HPI is to create battery-free devices that are powered solely from human interactions. Therefore, it is important that power generation and interactivity are aligned and not separated tasks. In this paper, a novel way of providing human power to interactive devices has been investigated using electromagnetic induction. The focus has been to explore and play with the fundamental principles of electromagnetic induction with the intention of evaluating its potential as a new type of interactive power generation. With the help of a physical prototype and an application to demonstrate its capabilities, the results show that electromagnetic induction could potentially be considered as a relatively easy way to build human-powered sources for interactive devices using this principle. / Under det senaste decenniet har vi sett ett ökande intresse för utformningen av interaktiv teknik som är begränsad i energianvändningen till det av våra kroppsliga förmågor. Detta fält kallas vanligen Human-Power Interaction (HPI). Målet med HPI är att skapa batterifria enheter som drivs enbart från mänskliga interaktioner. Därför är det viktigt att kraftproduktion och interaktivitet är anpassade till varandra och inte separerade aktiviteter. I denna rapport har ett nytt sätt att tillhandahålla mänsklig kraft till interaktiva enheter undersökts med hjälp av elektromagnetisk induktion. Fokus har varit att utforska och leka med de grundläggande principerna för elektromagnetisk induktion i avsikt att utvärdera dess potential som en ny typ av interaktiv kraftproduktion. Med hjälp av en fysisk prototyp och en tillämpning för att demonstrera dess förmåga, visar resultaten att elektromagnetisk induktion potentiellt kan ses som ett relativt enkelt sätt att bygga människodrivna källor för interaktiva enheter med denna princip.

The most common equipment used for attitude determination in small satellites are magnetometers. However, using magnetometers gives rise to many challenges. One of these challenges is the calibration of the magnetometer. Magnetometer calibration takes many factors into account. There are external and internal factors. External factors can be the satellite itself. Satellites are built of many complex subsystems. These subsystems can produce magnetic disturbances and affect the measurements taken by the magnetometer ,which also affects the attitude determination of the satellite. Internal factors are nonorthogonalityand scale factors. In this project, we aim to test different calibration methods and compare the results. Another objective is to provide a complete procedure for a calibration of the magnetometer using the Helmholtz coils. The comparison of the results with other methods can help with the decision of which should be used to calibrate the magnetometer onboard the satellite for future calibrations for MIST satellites. / En av de mest vanliga verktyg för attitydbestämning i små satteliter är magnetometer, men att använda magnetometer kan leda till många utmaningar, en av de kalibrering av magnetometern. Magnetometer kalibrering är beroende av många faktorer. Det finns inre och yttre faktorer. Yttre faktorer kan vara själva satelliten. Del system som bildar satelliten kan påverka mätningar i magnetometern och då påverkar attitydbestämning av hela satelliten. Inre faktorer är icke ortogonalitet och skalära faktorer. I det här projektet vi ska testa olika kalibrerings metoder och jämföra resultaten. Ett annat mål är att bygga en komplett procedur för att kalibrera magnetometer med hjälp av Helmholtz spolar. Jämförelsen och resultaten från kalibreringen visar hur det är möjligt att kalibrnetometer som är integrerad i satelliten för kommande kalibreringar i MIST. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm

Around the world, countries are increasingly considering carbon-free energy generation options as the threat of climate change grows. Small modular reactor designs, promising such carbon-free energy generation, are thriving worldwide with novel and innovative technologies that improve safety as well as economic performance. Canada is also considering small modular reactors (SMRs) as a means of achieving net zero carbon emissions by 2050. Some of these reactor designs utilize pressurized water for cooling and moderator. Reactors with pressurized water have been subjected to steam generator tube ruptures in the past, and a detailed investigation into the possible consequences of such incidents in SMRs should be conducted. In this research, a model for one of the newer designs, the NuScale Integrated Small Modular Reactor, was developed with the RELAP5-3D code for assessing safety related transients. The NuScale Small Modular Reactor incorporates helical coil steam generators within its reactor pressure vessel, which are more efficient in terms of heat transfer than the U-tube steam generators that are widely used in nuclear reactors. In the first part of the research, a detailed model is created and used to obtain steady state conditions with parameters collected from NuScale’s Final Safety Analysis Report (FSAR). The Steam Generator Tube Rupture event is analyzed in the second part of the work. Slight differences in the broken and intact steam generator pressures as well as decay heat removal system flow rates are seen in the comparison of reference values and calculated results. Among the reasons for those differences could be that the correlations used by the RELAP5-3D code for heat transfer coefficient and pressure drop in the helical coil steam generators are different than those of the NuScale proprietary code NRELAP5, with which the analyses have been performed in the FSAR. Also, post-dryout heat transfer at the exit of helical coil steam generators and evaporator sections could cause differences in the outlet conditions of the steam, resulting in different mass flow rates as well. The final section of the research simulates a comparable but more severe tube rupture incident without the availability of decay heat removal systems in order to assess the reactor’s emergency core cooling system reaction. Passive decay heat removal systems are crucial components for removing heat after reactor shutdown through heat exchangers that are submerged in the reactor pool and connected to steam generators by a closed loop. The containment pressures, the containment wall temperatures, and the peak fuel clad temperatures are considered to be the key design constraints that must be observed. Future work on this subject could include modifying the source code, adding specific correlations for helical coil steam generators, and comparing the results, as well as quantifying uncertainties in the SGTR event. Main parameters in the quantification of uncertainties would be reactor power, single phase and two-phase discharge coefficients from the break, trip signals and delays as well as break size and location. / Thesis / Master of Applied Science (MASc)

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