The increase of electronics in road vehicles comes along with a broad variety of possibilitiesin terms of safety, handling and comfort for the users. A rising complexityof the vehicle subsystems and components accompanies this development and has tobe managed by increased electronic control. More potential elements, such as sensors,actuators or software codes, can cause a failure independently or by mutually influencingeach other. There is a need of a structured approach to sort the faults from avehicle dynamics stability perspective.This thesis tries to solve this issue by suggesting a fault classification method and faulttolerantcontrol strategies. Focus is on typical faults of the electric driveline and thecontrol system, however mechanical and hydraulic faults are also considered. Duringthe work, a broad failure mode and effect analysis has been performed and the faultshave been modeled and grouped based on the effect on the vehicle dynamic behaviour.A method is proposed and evaluated, where faults are categorized into different levelsof controllability, i. e. levels on how easy or difficult it is to control a fault for the driver,but also for a control system.Further, fault-tolerant control strategies are suggested that can handle a fault with acritical controllability level. Two strategies are proposed and evaluated based on thecontrol allocation method and an electric vehicle with typical faults. It is shown thatthe control allocation approaches give less critical trajectory deviation compared to noactive control and a regular Electronic Stability Control algorithm.To conclude, this thesis work contributes with a methodology to analyse and developfault-tolerant solutions for electric vehicles with improved traffic safety. / <p>QC 20131010</p>

In vehicle control practice, there are some variables, such as lateral tire force, body slip angle and yaw rate, that cannot or is hard to be measured directly and accurately. Vehicle model, like the bicycle model, offers an alternative way to get them indirectly, however due to the widely existent simplification and inaccuracy of vehicle models, there are always biases and errors in prediction from them. When developing advanced vehicle control functions, it is necessary and significant to know these variables in relatively high precision. Kalman filter offers a choice to estimate these variables accurately with measurable variables and with vehicle model together. In this thesis, estimation models based on Extended Kalman Filter (EKF) and Uncented Kalman Filter (UKF) are built separately to evaluate the lateral tire force, body slip angel and yaw rate of two typical passenger vehicles. Matlab toolbox EKF/UKF developed by Simo Särkkä, et al. is used to implement the estimation models. By comparing their principle, algorithm and results, the better one for vehicle state estimation will be chosen and justified. The thesis is organized in the following 4 parts: First, EKF and UKF are studied from their theory and features. Second, vehicle model used for prediction in Kalman filter is build and justified. Third, algorithms of EKF and UKF for this specific case are analysed. EKF and UKF are then implemented based on the algorithms with the help of Matlab toolbox EKF/UKF. Finally, comparisons between EKF and UKF are presented and discussed.

BAE Systems Hägglunds has a long history of producing high performance terrain tracked vehicles (mostly for military applications), and they are now aiming at developing a tracked forwarder with similar techniques.The forwarder will be of series hybrid type where a diesel engine via a generator will power the motors (one for each drive wheel). Thanks to individually controlled motors and the gentle rubber tracks, this forwarder is calculated to have a considerably higher average speed in the terrain and to be more gentle to the soil. The forwarder with a weight of 11 metric tons and a load capacity of 15 metric tons is specified to have an average working speed of 7-10 km/h, a top speed in terrain of 15 km/h and a top speed on roads of 40 km/h.This master’s thesis aims at developing a conceptual design of the forwarder’s drive module which includes electric motor, gear unit, brake and drive wheel.To investigate if the requirements can be fulfilled a study of the dimensioning loading scenarios has been carried out. The resulting needs regarding the torque has been considered in order to determine the required gear ratios for different motor options. A planetary gear unit is intended for the supply of the gear ratio between the electric motor and the drive wheel and with the results from the study of the different loading scenarios models of the motor and gear unit could be chosen as reference models in the concept generation part. The concepts were evaluated with a Pugh matrix in order to choose the most suitable one for further development. In the further development work the CAD models have been detailed and a verifying FEM analysis of the base in the design has been performed.The result is a conceptual design where the electric motor and the gear unit have been placed inside of the drive wheel and a disc brake system has been placed outside of the drive wheel. As gear unit a system with two steps has been chosen for adaption to the current demands regarding gear ratio and available geometrical space. The chosen motor is a permanent magnet synchronous motor with a peak torque of 324 Nm, a nominal torque of 172 Nm and a maximum efficiency of 94 %. This will result in a fulfillment of the requirements regarding the performance of the forwarder. / BAE Systems Hägglunds som har en lång erfarenhet av att tillverka högpresterande terrängfordon med banddrift (främst för militära applikationer) satsar nu på att ta fram en skotare med banddrift.Skotaren är tänkt att vara av seriehybridtyp där en dieselmotor via en generator driver de fyra elmotorerna (en för varje bandställ). Tack vare individuella drivmotorer samt den för marken skonsamma gummibandsdriften beräknas denna skotare kunna framföras i en betydligt högre medelfart i terräng samtidigt som markförstöringen minskar drastiskt. Skotaren med en vikt på 11 ton samt en lastförmåga på 15 ton är specificerad att ha en effektiv skotarhastighet på 7-10 km/h, en toppfart i terräng på 15 km/h och en toppfart på väg på 40 km/h.Detta examensarbete syftar till att ta fram ett konstruktonskoncept för den tilltänkta skotarens drivmodul som innefattar elmotor, växelenhet, broms samt drivhjul.För att utreda huruvida de uppställda prestandakraven kan uppfyllas har en studie av dimensionerande lastfall utförts där en effekt på 150 kW från band till mark har antagits. Momentbehoven vid dessa lastfall har också studerats i syfte att bestämma utväxlingsbehoven för olika motoralternativ. En planetväxelenhet är tänkt att tillgodose utväxlingsbehovet från motor till drivhjul och med resultaten från lastfallsstudien kunde realistiska referensmodeller för motor och växel användas till den efterföljande konceptgenereringen där fyra olika koncept togs fram. Efter utvärdering av koncepten bland annat med hjälp av en Pugh-matris har ett koncept valts ut för vidareutveckling. I detta arbete har mer detaljerade CAD-modeller tagits fram och för själva basen i konstruktionen har en FEM-analys utförts.Resultatet är ett konstruktionskoncept där motor och växelenhet har placerats inuti drivhjulet och ett skivbromssystem har placerats utanför drivhjulet. Som växelenhet har ett beprövat system med två steg valts ut för anpassning till de rådande kraven på utväxling och geometriskt utrymme. Den motor som valts ut baserat på form och funktion är en permanentmagnetiserad synkronmotor som levererar ett maximalt moment på 324 Nm och ett nominellt moment på 172 Nm med en verkningsgrad på maximalt 94 %. Med dessa delsystem uppfylls då de specificerade prestandakraven på skotaren.

Contemporary studies of Intelligent Transportation Systems (ITS) use simulations of vehicular and communications traffic, due to the ethical and practical infeasibility of conducting experiments on real transportation networks. Different simulators have been developed for modeling real-time vehicular mobility and inter-vehicular communication under varying traffic and roadway conditions. While most model the effect of mobility on communications, only a few simulate the impact of inter-vehicular communication on vehicular mobility. None, moreover, are implemented as parallel or distributed frameworks: an essential requirement for the study of ITS applications in large-scale urban environments. As a starting point for developing such a framework, one contemporary simulator, VNetInetSim, was tested to determine its behavior under large loads. Testing determined that VNetInetSim's memory usage and execution time increase exponentially in the number of simulated vehicles while remaining relatively constant under increased communication traffic.

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第21918号 / 情博第701号 / 新制||情||120(附属図書館) / 京都大学大学院情報学研究科システム科学専攻 / (主査)准教授 西原 修, 教授 大塚 敏之, 教授 加納 学 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

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To produce competitive vehicles, their comfort is one important issue to take into account during the development process. The aim of this Master Thesis is to develop an on-line comfort evaluation tool in order to improve research and education in the field of vehicle comfort at the division of Vehicle Dynamics at the Royal Institute of Technology. Based on ISO standards concerning comfort an on-line evaluation tool has been developed using DASYLab, which is a software that allows creation of acquisition, control, simulation and analysis tasks. The developed tool has been evaluated by performing measurements of a VOLVO V40 equipped with sensors. Different sorts of surfaces and driving conditions have been investigated, and from this investigation one can conclude that the comfort tool works properly.

This thesis proposes a method to simulate the dynamics of an autonomous underwater vehicle towing another autonomous underwater vehicle of equivalent size using a marine cable in the vertical and horizontal plane. There is a coupling effect between the two vehicles because the towed vehicle is of equivalent size. This means that the towed vehicle cannot be modeled as just a payload but rather, must incorporate the forces and moments experienced and acting on it. In this work, only AUVs with symmetrical hulls are considered, where the towing AUV is moving at a constant velocity with a set thrust while the towed AUV has no thrust. The rope system is another important component that needs to be modeled correctly because the rope material and type significantly impact the motion of the vehicles. The rope system in this study is modeled using a numerical approach called the lumped mass spring damper method which is easy to understand and computationally inexpensive. The rope model accounts for buoyancy differences in different ropes and permits cable flexibility. This thesis enables us to study the motion of multiple combinations of different ropes and axi-symmetric types of underwater vehicles with any fixed or movable fin configuration. / M.S. / This thesis studies the motion of an autonomous underwater vehicle towing another autonomous underwater vehicle which is a large as it is. The towed vehicle cannot be assumed to be just a mass attached to the towing vehicle. There is an interaction between the two vehicle. The towed vehicle places a force on the towed vehicle and the towed vehicle likewise places a force on the towing vehicle. This interaction needs to be modeled correctly to fully capture the impact of both vehicles and their appendages. Additionally, the rope system poses a huge impact on the two vehicle depending on what type of rope is selected. Multiple factors affect the performance of a rope such as the shape and the elasticity. Some ropes may also be denser due to their material type and are less buoyant than others. These factors are considered in the modeling of the overall system and allows us to study different combinations of ropes and symmetric hulled autonomous underwater vehicles.

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