Today modern vehicles are expected to be safe, environmentally friendly, durable and economical. Monitoring the health of the vehicle is therefore more important than ever. As the complexity of vehicular systems increases the need for efficient monitoring methods has increased as well. Traditional methods of deriving models for the systems are today not as efficient as the complexity of the systems increases the time and skill needed to implement the models. An alternative is data driven methods where a collection of data associated with the behavior of the system is used to draw conclusions of the state of the system. Faults are however rare events and collecting sufficient data to cover all possible faults threatening a vehicle would be impossible. A method for drawing conclusions from limited historical data would therefore be desirable. In this thesis an algorithm using distiguishability as a method for fault classification and fault severity estimation is proposed. Historical data is interpolated over a fault severity vector using Gaussian process regression as a way to estimate fault modes for unknown fault sizes. The algorithm is then tested against validation data to evaluate the ability to detect and identify known fault classes and fault serveries, separate unknown fault classes from known fault classes, and estimate unknown fault sizes. The purpose of the study is to evaluate the possibility to use limited historical data to reduce the need for costly and time consuming data collection. The study shows promising results as fault class identification and fault size estimation using the proposed algorithm seem possible for fault sizes not included in the historical data.

In the early ship design process a quick overview of which shipdesign that could be the optimal choice for the intended usage needsto be investigated. Therefore the feasibility and accuracy ofinterpolating between measurement data from model resistance serieswhen estimating unknown hulls were conducted. A parametric study wasundertaken in order to investigate which parameters carry the mostimportance in regard to calm water resistance for semi-displacinghulls. In order to asses the whole estimation process one semidisplacing ship (FDS-5) and one bulk carrier with a bulbous bow (JBC)were estimated in regard to calm water resistance by using semiempirical methods and were later compared with CFD results. The CFDresults came from a in part parallel conducted work. The resultsshowed that it is possible to estimate the total resistance withsemi-empirical methods to an unknown hull by linear interpolationwith an accuracy of below 5% in the designed speed interval both forFDS-5 and JBC. The CFD simulations achieved a lower accuracy comparedto the semi-empirical approach, however by furhter calibrating themodels, the accuracy could potentially be improved. Linearinterpolation between two hulls in order to estimate an unknown hull,is only advised when the hulls are nearly identical. Meaning that thehulls must be of the same ship type and that only one parameter isallowed to differ compared to the unknown hull. The parametric studyresulted in parameter importance in falling order: Slenderness ratio,length-beam ratio, longitudinal prismatic coefficient, blockcoefficient and beam-draught ratio. Even though the CFD approach notyet is completely reliable, it could still be a useful complement tothe semi-empirical approach by calculating parameters such as adynamic wetted surface, resistance due to appendages or airresistance of the full-scale ship. Simply by incrementally increasingthe accuracy of individual resistance components an overallimprovement could potentially be achieved.

The periodic and determinist nature of wind turbine sound is believed to be a key factor for the high degreeof audibility. The present study investigated how alterations in fluctuating frequency affect the loudnessperception and detectability of wind turbine sound with and without background noise. The instantaneousloudness was judged for wind turbine sounds of different sonic character and altered fluctuating frequenciesusing the method of continuous judgment by category-ratio (CJCR) scaling. The obtained results showedlimited effects on the audibility despite altered fluctuating frequencies, rather it was found that the spectralcues dominate the loudness perception. These results was consistent for both measurements situation ofloudness and partial loudness.

Den här rapporten handlar om framtagningen av en bilstoldesign inom lättkonstruktioner. Stolen i fråga är anpassad efter ett steer-by-wire system, vilket innebär en datoriserad koppling mellan ratt, pedaler, motor och hjul. Rapporten behandlar vår arbetsgång med beräkningar, kravspecifikationer, labborationsresultat och materialforskning som ledde oss fram till vår slutliga produkt. Längst bak i rapporten finns alla bilagor. T.ex. den fullständiga kravspecifikationen, uppdraget som var givet från början samt beräkningar och koder. Stolen ska installeras i KTHs RCV och förhoppningen är att den även kommer användas i framtida koncept där hela störtbågen och chassit är anpassat utifrån viktoptimering.

Due to the continuously increasing demands on the efficiency of road passenger vehicles the National Highway  Safety Traffic Administration (NHTSA)  commissioned a project to determine the achievable mass savings on an average, mass produced passenger car which are obtainable with today’s or within close reach technology. The major part of this project is conducted at EDAG, Inc. One of the approaches made within this program is to reduce the weight of a vehicle’s body struc- ture by replacing the commonly on a mass production vehicle applied joining technology resistance spot welding with laser beam welding. The main advantage is the possibility to bisect the size of the flanges since laser welding requires less flange width compared to spot welding. A sample structure is remodeled twice to create one almost solely spot welded and one almost solely laser welded body structure of the same vehicle. Those body structures are represented by two FEM models. Proper representation of the joining technology is applied to both FEM models in preparation of NVH com- putation runs, ensuring the comparability of the two body structures regarding their performance. In cooperation with experienced production engineers two assembly layouts for the spot welded and the laser welded structures are developed. For those assembly layouts cost calculations are done to oppose the attained mass savings to the increase in production costs. The weight difference between the two versions is determined to a remarkable 12.2 kg for the ana- lyzed sample structure. The laser welded structure thereby displays a slightly improved NVH perfor- mance compared to the spot welded structure. Taking the exemplary cost increase for the assembly of certain parts of the lower body structure into account gave a weight saving efficiency of 4.58 $ per saved kg. For the field of automotive engineering this is a rather high value, mainly caused by the still very extensive costs for laser welding equipment. With laser welding technology being more and more  adopted in mass production applications and most probably due technical improvements those costs are likely to decrease within the next few years. Even more mass savings could be achieved by adapting the design of the body structure more to the usage of laser beam welding.

New trends for environmentally-friendly mobility are rising and expectations derived from customers are significant. Urban areas such as London or even Stockholm are starting to build urban tolls by charging conventional vehicles while full‐electric powered vehicles are exempted. Carbon taxes will be certainly introduced at the EU scale in the next decade, which will strengthen those expectations of   transportation  changes  especially  regarding  private  vehicles.  High  electrification  degree  of conventional  vehicles  has  to  be  performed  to  answer  to  those  expectations.  To  avoid  range restriction mainly related to the energy content limitations in battery electric vehicles (BEV), fuel tank has to be kept in conjunction with internal combustion engine. Thereby, according to this statement, the design of either a plug‐in hybrid electric vehicle (PHEV) or a range extender (REX) in a second extent with an extensive full‐electric range is relevant in the next decade.

Denna artikel presenterar en ny metod för optimering av fartygsrutter där 　era olika målfunktioner betraktas. Metoden bygger på en dynamisk programerings algoritm som påminner om Dijkstras grafsöknings algoritm, men som använder sig av Pareto-optimalitet för att hantera optimeringen av era målfunktioner. Metoden kan användas med både deterministiska och ensemble-väderprognoser. Fördelarna med att använda metoden tillsamans med deterministiska väderprognoser demonstreras i en jämförelse med en metod som baseras på Dijkstras algoritm. Jämförelsen visar, som väntat, att båda metoderna hittar samma rutt för minimal restid, men bara den metod som presenteras här hittar den rutt som minimerar bränsleförbrukningen, med en besparing på ungefär 15%. Utvärderingen av metoden tillsammans med ensemble-väderprognoser visar att det nns en stor fördel jämfört med att använda deterministiska väderprognoser om målet för optimeringen är minimerad bränsleförbrukning.

Simulation has become a very useful tool to predict the characteristics of a system and perform analysis of parameters without having to run too many tests. The advanced system engineering team of Continental Automotive uses a 0D simulation program, AMESim, to realize simulations of vehicle models. These simulations are used e.g. to predict the fuel consumption and CO2 emissions. A tool has been developed over the course of previous internships to realize the energy balance of AMESim vehicle models, which goal is to check the consistency of the models (no creation or loss of energy) and simplify their analysis. In this thesis, this tool has been further improved and developed through a comprehensive analysis. The computations have been checked and corrected to fit best with the AMESim results and obtain a consistent energy balance. The program has been adapted to hybrid vehicles and combustion losses computations were introduced. The program is coded in Matlab for the computations and in HMTL and JavaScript for the display. After the program was validated, it was used to realize a study on CO2 emissions. Three vehicle models were used. The influence of some parameters on the CO2 emissions was analyzed: the mass, aerodynamic resistance, rolling resistance, frictions and electric load. The aim of the study was to assess which parameters had the most influence on the CO2 emissions reduction in the perspective of the 95 g/km goal by 2020 set by the European Union. It was shown that the parameters have different effects on the vehicles CO2 emissions and that this effect varied from one vehicle to another. Substantial CO2 reduction can be achieved by improving some parameters, which makes it possible for the diesel vehicles to reach the 95 g/km in 2020 target set by the European Union. However, to achieve this goal with gasoline vehicles, the resort to hybridization will probably be needed. To assess the possible benefits of hybridization, a fourth vehicle model featuring mild hybridization was used. However, the decrease of CO2 emissions enabled by this type of hybrid vehicle would still not be sufficient to meet the 95 g/km target with gasoline vehicles.

This report describes the Master Thesis Project "Single Skin Versus Sandwich: Material Concept of a Patrol Boat in a Life Cycle Cost Perspective" performed at Kockums AB, Karlskrona, and reviewed and graded at the Royal Institute of Technology, Stockholm. There are both economic and environmental gains of developing fuel-efficient (light) vessels. Kockums have successfully produced ships in sandwich composite material, which is a light and stiff but expensive material concept. Building a vessel in single skin composite might result in a lower total life cycle cost due to several factors. Kockums wish to acquire more information of the affecting factors thus they have initiated this project. The project includes analyzing the accumulated cost of a concept patrol vessel while changing five variables: class notation ("Patrol" or "Passenger"), operational profile (10 or 35 knots), material concept (sandwich or single skin), material (carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP)) and choice of propulsion system (controllable pitch propeller (CPP), Inboard Performance System (IPS) or water jet) resulting in 48 versions of the vessel. First, the structural arrangement was adapted to the design loads of each version by iteratively seeking the maximal structural utilization of the elements. This was done by using a computational tool (RSTRUCT) that allows for effective scantling calculation. Then, the material, production and operational cost were determined for each version and the break-even points in terms of years of operation were found. The results gave insights concerning the characteristics of the different material concepts. The single skin versions were found to be both heavier (70 %) and more costly in terms of material and production cost (17 %) in relation to their sandwich equivalents. The break-even points between CFRP versions and GFRP versions were ranging between 4 and 14 years, depending on operational profile. For example, for a very low speed profile passenger vessel the break-even point was 40 years, implying that the GFRP version was the most beneficial choice. Regarding propulsion choices, the IPS system was the best choice for every version due to its high overall propulsive coefficient in a broad speed range.

This thesis treats the handling analysis of the Vehiconomic's three wheeled prototype vehicle "Smite". This is a light weight low emission vehicle intended for urban traffic but with sufficient power supply to manage highway driving as well. The purpose of this thesis is to evaluate the vehicle's stability and handling characteristics using the multibody simulation software ADAMS/Car, and also to try to find a more optimum configuration of the vehicle. The software in an excellent tool that allows you to examine different driving scenarios and easily make vehicle modifications, both quicker and safer than in real life. In order to obtain reliable results the simulations have to be as close to the reality as possible. The ADAMS/Car model was validated with the help of logged data, derived while performing physical test runs on an air strip. Maneuvers preformed were; Severe lane change, Slalom maneuver and a J-turn maneuver. Due to simplifications made in the virtual model, the validation did not generate satisfying results for all driving scenarios, but the model is considered good enough to help draw general conclusions about the vehicle's behavior. The largest simplification made was regarding the propelling of the vehicle, which was made front wheel driven instead of rear wheel driven. Due to the simple construction of the vehicle, very little room for modifications is available. The possibilities to affect the position of the center of gravity are very limited. The only room for modification available is in the front suspension system. Due to multiple mounting points for the spring/damper component, 12 different combinations of the front suspension system were generated. Additionally two more setups were made by changing the track width with the implementation of spacers. A suspension configuration was found that reduced the roll angle with approximately 10%.