This report is a master thesis performed at The Royal Institute of Technology divisions of Lightweight Structures and Naval Architecture in collaboration with the Swedish defence material administration, FMV. There are several naval submarines used by the Swedish navy and more to be built. The existing submarines have stability problems due to a high centre of gravity. Most parts on the existing vessels are made of steel, despite a position far above the vertical centre of gravity. By replacing the current steel casing covering the top part of the submarines pressure hull and the rudders placed on the tower, to a lighter composite structure it is possible to lower the centre of gravity. In this report the composite structure of the rudder and the casing has been weight optimized to achieve a structure as light as possible, but still able to withstand the forces applied to the structure. An analysis of the applied loads shows that the dimensioning loads vary between 50 and 90 kPa depending on the specified part. The results show that it is possible to decrease the weight of the rudder and casing with over 80 %. This would also give the submarine an increase in initial stability with over 40 % compared to the existing steel construction.

Commonly, when calculating ship responses one uses idealized wave spectra to represent the sea. In the idealized model, the sea is frequently assumed to consist of swell and windwaves, which are usually represented by idealized 1D wave spectra, and the directionality of wind-waves is accounted for by multiplication with a standard spreading function. In operational response predictions these idealized spectra are typically generated by extracted parameters from real directional 2D wave spectra obtained from a weather forecast, i.e. spectra that reflects the sea state conditions for the particular place and time. It is generally not known in a statistical sense how large the errors become when idealized wave spectra are used to represent 2D wave spectra, especially not regarding the directionality. The objective with the study is hence to assess the errors that arise when adopting this simplification. The analysis compares three ship types that cover different combinations of hull form, load condition and operational conditions: a 153m RORO ship, a 219 m PCTC and a 240m bulk carrier. Chosen response parameters are roll motion, vertical acceleration and wave added resistance, which were calculated in 12240 sea states, for 10 speeds and 36 courses for each ship. The sea states are forecast 2D spectra from the North Atlantic 25th of September 2012. Transfer functions were generated from the hull geometry and realistic load conditions at speeds 2-20 knots. For each sea state-speed-course combination, responses were calculated for 2D wave spectra and corresponding generalized spectra. The error is taken as the difference in response between results obtained with 2D and idealized spectra, using 2D-results as reference. Several statistical measures were used to represent the errors for one sea state with only one number, and among them the root-mean-square error (RMSE) and the worst possible error (WPE) are regarded most relevant. The results show that the relative error decreases with increasing share of wind waves and decreasing share of swell. Multi-directionality of wind waves causes large errors only for small waves, and it is concluded that for higher sea states (for which the wind waves are predominant) the Bretschneider representation with spreading function leads to small relative errors. Absolute errors are considered the only relevant for investigating the effect of the error on seakeeping calculations. In general, the RMS acceleration levels are in the order of percentages of one g for all ships. For the bulker, WPE and RMSE for wave added resistance was found to be 8.3% and 3.8% of the total calm-water hull resistance in general, and almost 50% in worst case. The roll angle bias could reach up to 15. Also, the effect of ship speed was investigated, and it shows that the error increases in general with higher speed. It is concluded that it is necessary to use 2D spectra in order to avoid large errors, and to keep performance predictions correct on average.

This thesis adopts a novel approach to propelling and controlling the dynamics of a vehicle by using autonomous corner modules (ACM). This configuration is characterised by vehicle controlled functions and distributed actuation and offers active and individual control of steering, camber, propulsion/braking and vertical load. Algorithms which control vehicles with ACMs from a state-space trajectory description are reviewed and further developed. This principle involves force allocation, where forces to each tyre are distributed within their limitations. One force allocation procedure proposed and used is based on a constrained, linear, least-square optimisation, where cost functions are used to favour solutions directed to specific attributes. The ACM configuration reduces tyre force constraints, due to lessen estrictions in wheel kinematics compared to conventional vehicles. Thus, the tyres can generate forces considerably differently, which in turn, enables a new motion pattern. This is used to control vehicle slip and vehicle yaw independently. The ACM shows one important potential; the extraordinary ability to ensure vehicle stability. This is feasible firstly due to closed-loop control of a large number of available actuators and secondly due to better use of adhesion potential. The ability to ensure vehicle stability was demonstrated by creating actuator faults. This thesis also offers an insight in ACM actuators and their interaction, as a result of the force allocation procedure. / QC 20101117

Situation awareness is a crucial capability of any autonomous system, including mining vehicles such as drill rigs and mine trucks. Typically situation awareness is interpreted as the capability of an autonomous system to interpret its surroundings and the intentions of other agents. The internal system awareness however, is often not receiving the same focus, even though the success of any given mission is completely dependent of the condition of the agents themselves. The internal system awareness in the form of vehicle health is the focus of this thesis. As the mining industry becomes increasingly automated, and vehicles become increasingly advanced, the need for condition monitoring and prognostics will continue to rise. This thesis explores data-driven methods that estimate the health of mining vehicles to accommodate those needs. We do so by utilizing available sensor signals, common on a large amount of mining vehicles, to make assessments of the current vehicle condition and tasks. The mining industry is characterized by small series of highly specialized vehicles, which affects the possibility to use more traditional prognostic solutions. The resulting health information can be used both to aid in tasks such as maintenance planning, but also as an important input to decision making for the planning system, i.e. how to run the vehicle for minimum wear and damage, while maintaining other mission objectives. The contributions include: a) A method to use operational data to estimate damage on the frame of a mine truck. This is done using system identification to find a model describing stresses in the structure with input from other sensors such as accelerometers, load sensors and pressure sensors. The estimated stress time signal is in turn used to calculate accumulated damage, and is shown to reveal interesting conclusions on driver behavior. b) A method to characterize the different driving tasks by using an accelerometer and a convolutional neural network. We show that the model is capable of classifying the vehicle task correctly in 96 % of the cases. And finally c), a system for underground road monitoring, where a quarter car model and a Kalman filter are used to generate an estimate of the road profile, while positioning the vehicle using inertial measurements and access point signal strength. / <p>Ytterligare forskningsfinansiär: Epiroc Rock Drills AB</p>

Background Motor vehicle collisions (MVCs) are a common cause of injury and death throughout the world. Following an MVC some patients will remain in their vehicles due to injury, the potential for injury or physical obstruction. Extrication is the process of removing injured or potentially injured patients from vehicles following a motor-vehicle collision. Current extrication practices are based on the principles of 'movement minimisation' with the purpose of minimising the incidence of avoidable secondary spinal injury. Movement minimisation adds time to the process of extrication and may result in an excess morbidity and mortality for patients with time dependent injuries. The current extrication approach has evolved without the application of evidence-based medicine (EBM) principles. The principles of EBM; consideration of the relevant scientific evidence, patient values and preferences and expert clinical judgement are used as a framework for this thesis. Aims and Objectives To develop evidence-based guidance for the extrication of patients trapped in motor vehicles by applying EBM principles to this area of practice. This will be achieved through: - Describing the injury patterns, morbidity and mortality of patients involved in MVCs (trapped and not trapped). - To analyse the movement associated with and the time taken to deliver across a variety of extrication methods. - Determining the perceptions of patients who have undergone vehicle extrication and describe their experiences of extrication. - Developing consensus-based guidelines for extrication.

Vehicles with different capabilities for automated driving will gradually be deployed in road transportation systems over the coming decades. Mixed traffic conditions may change the characteristics of the traffic flow dynamics.  Microscopic traffic simulation is used for studying traffic flow dynamics in transportation systems. By simulating the interactions between individual vehicles, effects caused by changes in the road infrastructure, by road closures, or by the number and the types of vehicles can be investigated. Impacts on traffic performance can be analyzed in terms of travel times, travel time delays, queue formations, or vehicle throughput. To evaluate the impact of automated driving on traffic performance using microscopic traffic simulation, existing microscopic driving models need to be further developed to describe automated driving.  The aim of this thesis is to investigate how to further develop microscopic traffic simulation models for automated driving. In this investigation, the aspects to consider in simulation experiments including automated driving are identified. These aspects are the vehicle system, the role of authorities, the role of the users, of the infrastructure, of connectivity features, and of the sensor-based perception of the vehicles. A microscopic traffic simulation experiment showing the possible effects on a motorway in terms of vehicle throughput and travel delays is presented.  A conceptual model that describes how driving automation systems deal with the perception tasks is proposed. Future research directions will focus on implementing this model for perception in traffic simulation platforms and on the modeling of lateral tactical maneuvers. iii

When designing a building, sound is one of the problems to take into account. Vibrating machines, such as ventilation fans, water pumps and compressors, generate structure-borne sound. The structure-borne sound travels up the structure of the building and generates sound in adjacent rooms. To be able to predict the sound radiated in the adjacent rooms when designing a building, a semi-analytical model has been developed. Using the incident vibrations from the floor plate where the vibrating machine is standing, the transmission loss in the junction between the floor plates and the wall plate is calculated. This can bed one in every junction in the building, creating a system of multiple junctions. The sound radiation to the adjacent rooms is later approximated using the velocity of the plates.The model is verified with measurements in two case studies. This shows that the model has good potential in predicting the normal acceleration amplitudes in the relevant plates. The two case studies have different geometric properties and different sources. The comparison between the model and the measurement gives similar results. The model analyses the output of the bending waves since this is the wave type that radiates sound, but longitudinal waves are present in the model. With only two case studies it is too early to say that the model works for all systems, but it could be used as a fist approach. The model, right now, is restricted to isotropic, homogeneous material without losses. A parametric study shows that the transmission loss is dependent on the ratio between the thicknesses of the floor plate and the wall plate. The ratio should be as large as possible to get a high transmission loss, but depends on how the junction is structured. / När en byggnad designas är ljud ett av problemen som behöver tas hänsyn till. Vibrereande maskiner, så som ventilationsfläktar, vattenpumpar och kompressorer genererar strukturburet ljud. Det strukturburna ljudet färdas upp genom strukturen i byggnaden och generarear ljud i närliggande rum. För att kunna förutspåljudavstrålningen i de närliggande rummen när en byggnad designas, har en semianalytisk model tagits fram. Genom att använda infalland vibrationer från golvplattan där den vibrerande maskinen står, kan transmissionsförlusterna i förbindelsen mellan golvplatttorna och väggplattorna beräknas. Detta kan göras för samtliga förbindelser i byggnaden och skapar då en system för flera förbindelser. Ljudalstringen till de närliggande rummen kan sedan beräknas genom att använda hasitgheten av de vibrerandeplattorna.Modellen verifieras med hjälp av mätningar i två fallstudier. Dessa visar att modellen har god potential för att förutspå de normala accelerations amplituderna i de relevanta plattorna som studeras. Båda studierna har olika geometriska egensakper samt olika vibrations källor. Jämförelse mellan modellen och mätningen visar liknade resultat. Modellen analyserar de utgående böjvågorna eftersom det är dessa som kommer alstra ljud. Däremot är longitudinalvågor närvarande i modellen. Med endast två fallstudierär det för tidigt att säga om modellen fungerar för alla typer av system, men den kananvändas som ett första synsätt när problematiken uppstår. För närvarande är modellenbegränsad till isotropisk och homogenisk material utan förluster. En parametrisk studie visar att transmissionsförlusten är beroende av förhållandet mellan tjockleken av golvplattan och väggplattan. Förhålladet mellan dem ska vara så stort som möjligt för att få en hög transmissionsförlust, men den är också beroende på hur själva förbidelsen ser ut.

High fuel saving potentials, increased load carrying capacities and therefore competitive advantages force the heavy goods vehicle industry to enhance the efforts towards comprehensive lightweight designs. Facing this challenge, the material evaluation in terms of simulations and physical testing of composite materials is required for the design against fatigue failure due to road introduced vibrations. Eliminating fatigue testing issues in order to gain acceptable and reproducible results, a future-oriented systematic approach on conducting constant amplitude tension-tension fatigue testing on a unidirectional composite material is presented. Following the material characterisation of the carbon/epoxy material in terms of tensile and shear properties as well as fibre volume fraction, several combinations of tab configurations and specimen geometries have been tested with regard to their suitability for fatigue testing. Finally, the unidirectional material was successfully tested under tension-tension fatigue and first elaborated test data were assessed. In conclusion, the usage of straight aluminium tabs completely clamped inside the grips and bonded to the straight-sided specimen with 3M DP420 adhesive, using ventilation during the test is the recommended test procedure. / Lastbilsindustrin tvingas öka ansträngningarna för omfattande viktbesparingar med lättviktskonstruktioner då dessa har konkurrenskraftiga fördelar med potential att minska bränsleförbrukningen samt öka den lastbärande kapaciteten. Genom att ta sig an denna utmaning kommer materialkarakterisering, provning och simulering av kompositmaterial vara av stor betydelse för att kunna konstruera produkter utsatta för cykliska laster från väginducerade vibrationer. Vid utmattningsprovning är det viktigt att kunna generera acceptabla och reproducerbara resultat. I denna rapport presenteras hur man kan undvika och eliminera problem vid utmattningsprovning, samt ett systematiskt tillvägagångsätt vid genomförande av utmattningsprovning med konstant amplitud för belastningen drag-drag på ett kompositmaterial med enkelriktad fiberorientering. Ett kolfiber/epoximaterial är karakteriserat och flertal kombinationer av tab-konfiguration och provstavsgeometri har testats, med avseende på lämplighet för utmattningsprovning. Slutligen har kolfiber/epoximaterialet provats med framgång under cyklisk drag-drag belastning i fiberriktningen. Slutsatsen för utmattningsprovning är att använda sig av raka aluminium tabbar helt fastklämda inuti greppen. Tabbarna limmas fast på provstaven med 3M DP420 lim. Ventilation är också rekommenderat under provning för att undvika en ökning av temperatur i provstaven.

This report presents a master’s thesis edition involving the Maribot Petrel project, which concerns the development of a long range aquatic UAV capable of vertical takeoff from water in order to hop between different locations and to perform measurements in archipelago conditions. A concept evaluation phase was performed where multiple aquatic UAV ideas were investigated. This phase led to the conclusion that a flying wing with nose-tilting engine was the best concept to further invest in. Further, two prototypes of different sizes were then constructed and tested with positive results. The concept proved to be a promising platform for further development of the project. / Denna rapport sammanfattar ett examensarbete som utförts under projektet Maribot Petrel. Projektet omfattar utvecklingen av en obemannad, vatten anpassadoch långdistans drönare kapabel till vertikal start från vattnet med uppgiftatt hoppa mellan olika positioner och utföra mätningar i skärgårdsmiljö. Initialt utfördes en utvärdering av olika drönarkoncept som kunde användas. Detta resulterade i att idén om en flygande vinge med roterbar motor i nosen ansågs vara bäst lämpad att fortsatt investera i. Efter detta byggdes två prototyperi olika storlekar som sedan testades med positiva resultat. Detta koncept visade sig vara en lovande plattform för fortsatt utveckling av projektet.

Steering of prepreg tows in an automated fibre placement (AFP) process allows geodesic layup trajectory over a doubly-curved surface, as well as the potential to improve the efficiency of composite structures by tailoring their stiffness. However, defects (such as out-of-plane buckling and tow pull off) are commonly generated when the steering radius exceeds a critical limit, which impact the mechanical properties of the finished product. The in- and out-of-plane material properties of the prepreg tows have been shown to significantly influence the quality of the layup. In this thesis, in-plane shear behaviour of uncured IMA-M21 unidirectional (UD) prepreg was characterised using an off-axis tensile test to derive material parameters for process models to predict steering limits and defects. Test parameters, such as shear strain rates and temperatures, that were investigated were consistent to the actual AFP process. The results demonstrates the expected strain-rate and temperature dependencies related to the resins viscoelastic behaviour. Subsequently, a novel micro-mechanical finite element (FE) simulation of a 3-dimensional UD prepreg unit cell in pure shear was conducted to gain qualitative insights into the complex rheological behaviour at play. It effectively demonstrates how fibre friction, resin viscosity and shear strain rates influence the load transfer between fibres and melt, as well as the movement of fibres during the shearing process. These were reflected in the shear stress-strain curves generated in the simulation and elastic micro-buckling observed in the fibre elements. The results pave a way for future development of a robust material model for predicting the critical process parameters to achieve quality layups from AFP steering process. / Automated Fibre Placement (AFP) är en automatiserad metod för tillverkning av högpresterande fiberkompositkomponenter inom främst flygindustrin. AFP gör det möjligt att styra fiberupplägget genom att följa den geodetiska vägen ¨over dubbelkrökta ytor. Detta ger effektiva kompositstrukturer där fibrerna tillåts ligga i precis de rätta, skräddarsydda riktningarna för bästa möjliga mekaniska prestanda. Det finns dock begränsningar, speciellt när det gäller kritiska styrradier där defekter som fiberbuckling och fiber-släpp lätt uppstår. Dessa defekter påverkar den färdiga produktens mekaniska egenskaper. Skjuvegenskaperna i planet hos de ohärdade prepregens fiberbuntar och buckling ut ur planet har visat sig ha stor inverkan på kvalitén hos fiberuppläggen. I denna avhandling undersöks skjuvegenskaperna hos ohärdad IMA-M21 enkelriktad (UD) prepreg med hjälp av ett icke-axiellt dragprov. Syftet ¨ar att ta fram materialdata för simulering av fiberuppläggets begränsningar, för att kunna bestämma hur AFPn bör styras. Modellerna ska ¨aven prediktera de defekter som uppstår. Testparametrar så som skjuvhastigheter och temperaturer undersöks för att efterlikna den verkliga AFP-processen. Resultaten fångar det förväntade skjuvhastighet- och temperaturberoende som ges av matrisens viskoelastiska egenskaper. Baserat på dessa modeller tas en nya mikromekanisk modell fram som implementerad i Finita Element (FE) ger kvalitativ inblick i den komplexa reologin som inverkar. Modellen påvisar tydligt hur fiberfriktion, matrisens viskositet- och skjuvhastighet påverkar kraftföreningen mellan fiber och matris, så väl som förflyttningen av fibrer under skjuvprocessen. Resultaten banar väg för framtida utveckling av robusta materialmodeller för att kunna prediktera kritiska parametrar för att åstadkomma högkvalitativa