In this project, a chassis concept has been developed for a battery-powered autonomousvehicle. The vehicle is intended to be used at an airport for transporting people betweendifferent terminals. The objective is to develop a chassis which is anchored with modernrequirements and futuristic research based on conventional chassis design methods in orderto find an optimal solution for this specific vehicle. Literature studies have been conductedon future batteries, types of chassis, chassis materials, and optimal cross-sections. Thechassis materials have also been analyzed from an environmental perspective and life cycleanalysis (LCA). Based on this, it was found that the “skateboard” chassis model was optimalfor the intended vehicle while Advanced High Strength Steel (AHSS) proved to be the mostsuitable material for the load-bearing structure. It is essential to keep in mind that thisproject has been carried out on a conceptual level within the framework of a degree project.This master thesis project aims to provide a solid benchmark for further development andresearch within the subject. / I detta projekt har ett chassi koncept tagits fram för ett batteridrivet autonomt fordon. Fordonet är tänkt att användas på en flygplats för att transportera människor mellan olikaterminaler. Syftet är att chassit skall vara förankrat med moderna krav och futuristiskforskning genom att uppdatera och jämföra klassiska metoder inom chassi utveckling föratt hitta en optimal lösning för det specifika fordonet. Litteraturstudier har genomförts ochberört bl.a. framtida batterier, chassi typer, chassi material samt optimala tvärsnitt. Chassimaterialenhar även analyserats ur ett miljöperspektiv och livscykelanalys. Baserat på dettakunde det konstateras att ett chassi med en ”skateboard” utformning är optimal för detavsedda fordonet varav kolstål visade sig vara det mest lämpade materialet för den bärandestrukturen. Det är viktigt att ha i åtanke att detta projekt har utförts på en konceptuellnivå inom ramarna för ett examensarbete. Detta examensarbete inom fordonsteknik syftartill att ge en stabil grund för vidareutveckling och forskning inom ämnet.

Carrying around 80-90% of world volume of goods, the shipping industry has a considerable environmental impact. The International Maritime Organization (IMO) fixed a 50% greenhouse gases emission reduction target by 2050 with respect to 2008 levels. Toward the objective of sustainable shipping, Wallenius Marine, together with KTH Royal Institute of Technology and SSPA Sweden, launched the project to develop a wind powered pure car carrier ship. The 200 meters long vessel is powered by four 360 degrees rotating upright wings that allow sailing in all conceivable wind conditions. The implementation of such concept strongly depends on the aerodynamic properties of the multi-wings system. However, its assessment is challenging due to flow interactions between the wings.The main goal of the study is to investigate and find a suitable wing design and configuration to propel the ship only using wind power, ie when the installed engine power is off. The first task of this study was to determine the reliability and limitations of the aero-modelling tools developed by KTH including a 2D wing trimming optimizer and a vortex lattice method code. Flapped-wing and symmetrical wing (NACA-4 digits profiles) rig designs have been investigated. The flapped wing profile enhances by 30% the thrust power of the multi-rig system compared to a symmetrical wing profile for same arrangement on deck and total sails area. The “rectangle” disposition of the rigs on deck appeared to be more performant than the in-line arrangement. Indeed, this configuration allows to sail with a larger range of incident wind angles (closer to the wind) and with higher vessel’s speed than the base design one. Further numerical testing using more accurate tools that can take turbulence effects into account, such as CFD and model testing in wind tunnel or real conditions may be done to validate the conclusions raised by this study. / Sjöfarten står för cirka 80-90% av den sammanlagda globala transportvolymen och har en betydande miljöpåverkan. IMO1 har satt upp som mål att utsläpp av växthusgaser skall halveras fram till 2050 med avseende på 2008 års nivåer. I ett steg mot målet om hållbar sjöfart inledde Wallenius Marine tillsammans med Kungliga Tekniska Högskolan och SSPA Sverige ett projekt för att utveckla ett av vindkraft drivet bilfraktsfartyg. Det 200 meter långa fartyget drivs av fyra stycken, 360 grader roterbara, upprättstående vingar som möjliggör segling under alla tänkbara vindförhållanden. Genomförandet av ett sådant koncept beror starkt på vingarnas aerodynamiska egenskaper. Att bedöma prestandan för detta komplexa system är utmanande på grund av intrikata flödesinteraktioner vingar sinsemellan.Studiens huvudmål är att finna bästa möjliga konstruktion för den aerodynamiska nordningen då fartyget drivs uteslutande med vindkraft, alltså då den installerade motoreffekten inte brukas. Den första uppgiften för denna studie var att bestämma användningsområdet för de flygmodelleringsverktyg som utvecklats av KTH inklusive en 2D-wing-trimningsoptimerare och en VLM-kod (Vortex Lattice Method). Riggkonstruktioner med klappvingar och symmetrisk vinge (NACA-4-siffror) har undersökts. Vingar med klaffar kan förbättra de aerodynamiska egenskaperna med 30% kontra vingar med symmetrisk vingprofil. Att placera vingarna i en rektangel tycks vara fördelaktigt mot att placera dem i linje. Denna konfiguration medger segling under ett större vindvinkelområde, dvs ’närmare vinden’, och med högre fartygshastighet än grunddesignen. Ytterligare utvärdering med noggrannare verktyg som tar hänsyn till turbulenseffekter, såsom CFD, modelltestning i vindtunnel eller skalade tester under verkliga förhållanden kan göras för att validera slutsatserna av denna studie.

Combustion engines in boats cause several environmental problems, such as greenhouse gas emissions and acidication of oceans. Most of these problems can be reduced by replacing the combustion engines with electric boats. The limited range is one of the main constraints for electric boats, and in order to decrease the energy consumption, applicable resistance prediction methods are necessary in the hull design process. X Shore, which is a start-up company in the electric boat sector, lacks a systematic way of predicting resistance in an early design phase. In this study, four well-known methods - CFD, Holtrop & Mennen, the Savitsky method and model test - have been applied in order to predict resistance for a test hull. The study is limited to bare hull resistance and calm water conditions. CFD simulations are applied using the software ANSYS FLUENT 19:0. The simulations were based on the Reynolds Average Navier-Stokes equations with SST k-ω as turbulence model together with the volume of fluid method describing the two-phased ow of both water and air surrounding the hull. The semi-empirical methods, Holtrop & Mennen and the Savitsky method, are applied through a program in Python 3, developed by the authors. The results from each method have been compared and since model tests have been conducted outside of this study, the model test results will serve as reference. To evaluate the methods, a number of evaluation criteria are identied and evaluated through a Pugh Matrix, a systems engineering tool. Holtrop & Mennen predicts the resistance with low accuracy and consistency, and the error varies between 2:2% and 70:6%. The CFD simulations result in acceptable resistance predictions with good precision for the speeds 4 - 6 knots, with an average deviation of the absolute values as12:28% which is slightly higher than the errors found in previous studies. However, the method shows inconsistency for the higher speeds where the deviation varies between 1:77% and - 43:39%. The Savitsky method predicts accurate results with good precision for planing speeds, but also for the speeds 7 and 8 knots. The method is under-predicting the resistance for all speeds except for 7 knots, where the total resistance is 10:7% higher than for model tests. In the speed range 8 - 32 knots, the average error is an under-estimation of 17:58%. Furthermore, the trim angles predicted by the Savitsky method correspond well with the trim angles from the model test. In conclusion, the recommendation to X Shore is to apply the Savitsky method when its applicability criteria are fulfilled, and CFD for the lowest speeds, where the Savitsky method is not applicable. / Förbränningsmotorer i båtar orsakar era miljöproblem, som exempelvis utsläpp av växthusgaser och försurning av hav. De flesta av dessa problem kan minskas genom att ersätta båtar med förbränningsmotorer med elbåtar. Den begränsade körsträckan är en av de största begränsningarna för elbåtar, och för att minska energiförbrukningen behövs metoder för att uppskatta motståndet under designstadiet. X Shore, ett startup-företag i elbåtsbranchen, saknar ett systematiskt tillvägagångssätt för att uppskatta motstånd i tidiga skeden i designprocessen. I den här studien har fyra välkända metoder - CFD, Holtrop & Mennen, Savitsky-metoden och modelltester - applicerats för att uppskatta motståndet hos ett testskrov. Studien är begränsad till ett skrov utan bihang och lugnvattenmotstånd. CFD-simuleringar har gjorts i mjukvaran  ANSYS FLUENT 19.0. Simuleringarna är baserade på Reynolds Average Navier-Stokes ekvationer och turbulensmodellen SST k - ω har använts tillsammans med metoden volume of fluid som beskriver ödet av både vatten och luft runt skrovet. De semi-empiriska metoderna, Holtrop & Mennen och Savitsky-metoden, har applicerats genom ett program i Python 3 som utvecklats av författarna. Resultaten från alla metoder har jämförts, och eftersom modelltester genomförts på detta skrov tidigare har de resultaten använts som referensvärden. Ett antal kriterier har identifierats och en Pugh-matris har använts för utvärdering av metoderna. Holtrop & Mennen uppskattar motståndet med låg noggrannhet och precision, felen varierar mellan 2:2% och 70:6%. CFD-simuleringarna ger acceptabla resultat av motståndsberäkningarna för hastigheterna 4 - 6 knop, med ett genomsnittligt absolut fel på 12:28% vilket är något högre än avvikelserna presenterade i tidigare studier. För högre hastigheter uppvisar metoden lägre precision där avvikelsen varierar mellan 1:77% och - 43:39%. Savitsky-metoden ger resultat med hög noggrannhet och god precision för planingshastigheter, men även för hastigheterna 7 och 8 knop. Metoden underskattar motståndet för alla hastigheter förutom för 7 knop där motståndet är 10:7% högre än för modelltesterna. I hastighetsintervallet 8 - 32 knop är det genomsnittliga felet en underskattning på 17:58%. Vidare överensstämmer trimvinkeln från Savitsky-metoden bra med resultaten från modelltesterna. Sammanfattningsvis rekommenderas X Shore att använda Savitsky-metoden när dess kriterier för tillämplighet är uppfyllda och CFD för de lägsta hastigheterna när Savitsky-metoden inte är tillämpbar.

The deployment of long combination vehicles (LCVs) is currently in progress in Sweden. LCV refers to heavy vehicles that are longer than 25.25 m, which is the conventional length limit in Swedish regulations. LCVs reduce operational costs, improve fuel efficiency and reduce CO2 emission per ton-km. Despite their numerous advantages, a question that still revolves around these vehicles is how they perform on the road. Although this question has been answered using simulations, an analysis using real traffic data is still missing.  This thesis assesses the performance of LCVs using naturalistic driving data (NDD). The performance assessment is done using Performance-based standards (PBS) measures. PBS is a regulatory scheme for heavy vehicles, such as LCVs, that includes performance measures with a quantified required level of performance. The main PBS measures used in this thesis are rearward amplification, low-speed swept path, high-speed transient offtracking, and high-speed steady-state offtracking. Rearward amplification represents the amplification of motions in the rear end of a vehicle combination, which relates to its stability, and the remaining three are indicative of the space that the vehicles occupy in different scenarios. The steering reversal rate is also employed to compute the cognitive workload of the drivers in low-speed scenarios.  Two LCV combinations are considered for analysis, namely an A-double composed of a tractor-semitrailer-dolly-semitrailer/tractor-semitrailer-full trailer and a DuoCAT composed of a truck hauling two centre-axle trailers. Four scenarios are of interest to this thesis: lane changes, manoeuvring through roundabouts, turning in intersections and negotiating tight curves. The thesis presents three contributions outlining the analysis methodologies, followed by a discussion of the results obtained from the analysis.  The first contribution involves developing an algorithm to extract lane changes from the NDD of LCVs. The algorithm is used against the data obtained from A-doubles. The results indicate that A-doubles adhere to proposed safety limits during lane changes.  The second contribution assesses the performance of A-double in round-abouts using NDD. Various roundabouts with different radii are considered. The vehicle occupies more space with lower radius roundabouts than higher radius roundabouts. The space occupied in all the cases is below the proposed safety limit. However, steerable axles might be needed for smaller roundabouts than those considered in this study. Additionally, the driver’s cognitive work-load is found to vary with the roundabout’s radius, with drivers navigating higher-radius roundabouts more easily.  The third contribution deals with the performance evaluation of DuoCAT across four scenarios, followed by the comparison with A-double. The results indicate that the A-double and the DuoCAT are stable and have good tracking performance in most cases. The A-double is observed to be slightly more stable in lane changes, whereas the DuoCAT has slightly better manoeuvrability at low-speed scenarios such as roundabouts and intersections. / Introduceringen av långa fordonskombinationer (LCV) pågår för närvarande i Sverige vilket ger en möjlighet att minska driftskostnader samtidigt som bränsleeffektiviteten förbättras och koldioxidutsläppen per ton-km reduceras. LCV avser tunga fordon som är längre än 25,25 meter, vilket är den konventionella längdgränsen enligt svenska regler. Trots fördelarna är en fråga hur dessa fordon presterar på väg. Den här avhandlingen studerar och analyserar den frågan med hjälp av naturalistisk kördata (NDD) från experiment med LCV. Prestandabedömningen görs med hjälp av prestandabaserade standarder (PBS). PBS är ett regleringssystem för tunga fordon, såsom LCV, som kvantifierar och kravställer fordonets beteende. De huvudsakliga PBS-måtten som används i denna avhandling är bakåtförstärkning, spåravvikelse och svept area i låg hastighet. Bakåtförstärkning representerar förstärkningen av rörelser från den främre till den bakre delen av en fordonskombination, vilket relaterar till dess stabilitet, och de två återstående indikerar det utrymme som fordonen upp-tar i olika scenarier. Dessutom används styråtervändningshastigheten (SRR) för att beräkna förarnas kognitiva arbetsbelastning vid låga hastigheter, exempelvis vid körning i rondeller och korsningar. Två LCV varianter studeras i denna avhandling, en A-dubbel bestående av dragbil-påhängsvagn-dolly-påhängsvagn/dragbil-påhängsvagn-släpvagn samt en Duo-kärra bestående av en lastbil som drar två släpvagnar med centrerade ax-lar. Fyra scenarier är av intresse för denna avhandling: filbyten, manövrering genom rondeller, svängning i korsningar och körning i snäva kurvor. Avhandlingen presenterar tre bidrag som beskriver analysmetoderna och efterföljande resultatdiskussioner. I det första bidraget utvecklas en algoritm för att extrahera filbyten från naturalistisk kördata av LCV fordon där metoden används på data från A-dubbelfordon. Resultaten indikerar att A-dubbelfordon håller sig till föreslagna säkerhetsgränser under filbyten. I det andra bidraget bedöms prestandan hos ett A-dubbelfordon i rondeller med hjälp av NDD. Olika rondeller med olika radier studeras. Fordonet upptar mer utrymme i rondeller med mindre radie jämfört med rondeller med större radie och det upptagna utrymmet ligger i alla undersökta fall under den föreslagna säkerhetsgränsen. För mindre rondeller än de som tas upp i denna studie kan styrbara axlar behövas. Dessutom visas att förarens kognitiva belastning varierar med rondellens radie där förare som navigerar större rondeller har en lägre kognitiv belastning. Det tredje bidraget handlar om prestandautvärdering av Duo-kärrafordon över fyra scenarier, följt av jämförelsen med A-dubbelfordon. Resultaten indikerar att både A-dubbelfordon och Duo-kärrafordon är stabila och har god spårningsprestanda i de flesta fallen. A-dubbelfordon observeras vara något mer stabil i filbyten, medan Duo-kärrafordon har något bättre manövrerbarhet vid låghastighetsscenarier som rondeller och korsningar.

Unlike many terrestrial applications, GPS is unavailable to autonomous underwater vehicles (AUVs) while submerged due to the rapid attenuation of radio frequency signals in seawater. Underwater vehicles often use other navigation technologies. This thesis describes a range-based acoustic navigation system that utilizes range measurements from a single moving transponder with a known location to estimate the position of an AUV in geodetic coordinates. Additionally, the navigation system simultaneously estimates the currents acting on the AUV. Thus the navigation system can be used in locations where currents are unknown. The main contribution of this work is the implementation of a range-based navigation system in geodetic coordinates for an AUV. This range-based navigation system is implemented in the World Geodetic System 1984 (WGS 84) coordinate reference system. The navigation system is not restricted to the WGS 84 ellipsoid and can be applied to any reference ellipsoid. This thesis documents the formulation of the navigation system in geodetic coordinates. Experimental data gathered in Claytor Lake, VA, and the Chesapeake Bay is presented. / Master of Science

The deployment of long combination vehicles (LCVs) is currently in progress in Sweden. LCV refers to heavy vehicles that are longer than 25.25 m, which is the conventional length limit in Swedish regulations. LCVs reduce operational costs, improve fuel efficiency and reduce CO2 emission per ton-km. Despite their numerous advantages, a question that still revolves around these vehicles is how they perform on the road. Although this question has been answered using simulations, an analysis using real traffic data is still missing.  This thesis assesses the performance of LCVs using naturalistic driving data (NDD). The performance assessment is done using Performance-based standards (PBS) measures. PBS is a regulatory scheme for heavy vehicles, such as LCVs, that includes performance measures with a quantified required level of performance. The main PBS measures used in this thesis are rearward amplification, low-speed swept path, high-speed transient offtracking, and high-speed steady-state offtracking. Rearward amplification represents the amplification of motions in the rear end of a vehicle combination, which relates to its stability, and the remaining three are indicative of the space that the vehicles occupy in different scenarios. The steering reversal rate is also employed to compute the cognitive workload of the drivers in low-speed scenarios.  Two LCV combinations are considered for analysis, namely an A-double composed of a tractor-semitrailer-dolly-semitrailer/tractor-semitrailer-full trailer and a DuoCAT composed of a truck hauling two centre-axle trailers. Four scenarios are of interest to this thesis: lane changes, manoeuvring through roundabouts, turning in intersections and negotiating tight curves. The thesis presents three contributions outlining the analysis methodologies, followed by a discussion of the results obtained from the analysis. / Introduceringen av långa fordonskombinationer (LCV) pågår för närvarande i Sverige vilket ger en möjlighet att minska driftskostnader samtidigt som bränsleeffektiviteten förbättras och koldioxidutsläppen per ton-km reduceras. LCV avser tunga fordon som är längre än 25,25 meter, vilket är den konventionella längdgränsen enligt svenska regler. Trots fördelarna är en fråga hur dessa fordon presterar på väg. Den här avhandlingen studerar och analyserar den frågan med hjälp av naturalistisk kördata (NDD) från experiment med LCV. Prestandabedömningen görs med hjälp av prestandabaserade standarder (PBS). PBS är ett regleringssystem för tunga fordon, såsom LCV, som kvantifierar och kravställer fordonets beteende. De huvudsakliga PBS-måtten som används i denna avhandling är bakåtförstärkning, spåravvikelse och svept area i låg hastighet. Bakåtförstärkning representerar förstärkningen av rörelser från den främre till den bakre delen av en fordonskombination, vilket relaterar till dess stabilitet, och de två återstående indikerar det utrymme som fordonen upp-tar i olika scenarier. Dessutom används styråtervändningshastigheten (SRR) för att beräkna förarnas kognitiva arbetsbelastning vid låga hastigheter, exempelvis vid körning i rondeller och korsningar. Två LCV varianter studeras i denna avhandling, en A-dubbel bestående av dragbil-påhängsvagn-dolly-påhängsvagn/dragbil-påhängsvagn-släpvagn samt en Duo-kärra bestående av en lastbil som drar två släpvagnar med centrerade ax-lar. Fyra scenarier är av intresse för denna avhandling: filbyten, manövrering genom rondeller, svängning i korsningar och körning i snäva kurvor. Avhandlingen presenterar tre bidrag som beskriver analysmetoderna och efterföljande resultatdiskussioner. / HCT-II

This dissertation is focused on the quantitative metrics of performance, cost, and reliability for future launch vehicles. Methods are developed that hold performance constant for a required mission and payload so that cost and reliability can be traded. Reliability strategies such as reducing the number of engines, increasing the thrust-to-weight ratio, and adding redundant subsystems all increase launch vehicle reliability. However, there are few references that illustrate the cost of increasing launch vehicle reliability in a disciplined, integrated approach. For launch vehicle design, integrated performance, cost, and reliability disciplines are required to show the sensitivity of cost to different reliability strategies. A methodology is presented that demonstrates how to create the necessary launch vehicle reliability models and integrate them with the performance and cost disciplines. An integrated environment is developed for conceptual design that can rapidly assess thousands of launch vehicle configurations. The design process begins with a feasible launch vehicle configuration and its mission objectives. The performance disciplines, such as trajectory analysis, propulsion, and mass estimation are modeled to include the effects of using different reliability strategies. Reliability models are created based upon the launch vehicle configuration. Engine reliability receives additional attention because engines are historically one of the leading causes of launch vehicle failure. Additionally, the reliability of the propulsion subsystem changes dynamically when a launch vehicle design includes engine out capability. Cost estimating techniques which use parametric models are employed to capture the dependencies on system cost of increasing launch vehicle reliability. Uncertainty analysis is included within the cost and reliability disciplines because of the limited historical database for launch vehicles. Optimization is applied within the integrated design environment to find the best launch vehicle configuration based upon a particular weighting of cost and reliability. The results show that both the Saturn V and future launch vehicles could be optimized to be significantly cheaper, be more reliable, or have a compromise solution by illustrating how cost and reliability are coupled with vehicle configuration changes.

We present a novel approach for vehicle detection and tracking in highway surveillance videos. This method incorporates well-studied computer vision and machine learning techniques to form an unsupervised system, where vehicles are automatically "learned" from video sequences. First an enhanced adaptive background mixture model is used to identify positive and negative examples. Then a video-specific classifier is trained with these examples. Both the background model and the trained classifier are used in conjunction to detect vehicles in a frame. Tracking is achieved by a simplified multi-hypotheses approach. An over-complete set of tracks is created considering every observation within a time interval. As needed hypothesized detections are generated to force continuous tracks. Finally, a scoring function is used to separate the valid tracks in the over-complete set. The proposed detection and tracking algorithm is tested in a challenging application; vehicle counting. Our method achieved very accurate results in three traffic surveillance videos that are significantly different in terms of view-point, quality and clutter. / text

Vehicle location and tracking has a variety of commercial applications and none of the techniques currently used can provide accurate results in all situations. This thesis details a preliminary investigation into a new location estimation method which uses optical environmental data, gathered by the vehicle during motion, to locate and track vehicle positions by comparing said data to pre-recorded optical maps of the intended location space. The design and implementation of an optical data recorder is presented. The map creation process is detailed and the location algorithm, based on a particle filter, is described in full. System tests were performed offline on a desktop PC using real world data collected by the data recorder and their results are presented. These tests show good performance for the system tracking the vehicle once its approximate location is determined. However locating a vehicle from scratch appears to be infeasible in a realistically large location space.

The gradual decline in global oil reserves and the presence of ever so stringent emissions rules around the world have created an urgent need for the production of automobiles with improved fuel economy. HEVs (hybrid electric vehicles) have proved a viable option to guaranteeing improved fuel economy and reduced emissions. The fuel consumption benefits which can be realised when utilising HEV architecture are dependent on how much braking energy is regenerated, and how well the regenerated energy is utilised. The challenge in developing a real-time HEV control strategy lies in the satisfaction of often conflicting control constraints involving fuel consumption, emissions and driveability without over-depleting the battery state of charge at the end of the defined driving cycle. Reviewed literature indicates some research gaps and hence exploitable study areas for which this thesis intends to address. For example, despite the research advances made, HEV energy management is still lacking in several key areas: optimisation of braking energy regeneration; real-time sub-optimal control of HEV for robustness, charge sustenance and fuel reduction; and real-time vehicle speed control. Consequently, this thesis aims to primarily develop novel real-time near-optimal control strategies for a parallel HEV, with a view to achieving robustness, fuel savings and charge sustenance simultaneously, under various levels of obtainable driving information (no route preview information, partial route preview information). Using a validated HEV dynamic simulation model, the following novel formulations are proposed in this thesis and subsequently evaluated in real time: 1. A simple grouping system useful for classifying standard and real-world driving cycles on the basis of aggressivity and road type. 2. A simple and effective near-optimal heuristic control strategy with no access to route preview information. 3. A dynamic programming-inspired real-time near-optimal control strategy with no access to route preview information. 4. An ECMS (Equivalent Consumption Minimisation Strategy) inspired real-time near-optimal control strategy with no access to route preview information. 5. An ECMS-inspired real-time near-optimal control strategy with partial access to route preview information. 6. A dynamic programming based route-optimal vehicle speed control strategy which accounts for real-time dynamic effects like engine braking, while solving an optimisation problem involving the maximisation of fuel savings with little or no penalty to trip time. 7. A real-time vehicle speed control approach, which is based on smoothing the speed trajectory of the lead vehicle, consequently reducing the acceleration and deceleration events that the intelligent vehicle (follower vehicle) will undergo. This smoothing effect translates into reduced fuel consumption, which tends to increase with increasing traffic preview window. Among other studies performed in this thesis, the fuel savings potential of the proposed near-optimal controllers was investigated in real time over standard driving cycles and real-world driving profiles. Results from these analyses show that, over standard driving cycles, properly formulated near-optimal real-time controllers are able to achieve a fuel savings potential within 0.03% to 3.71% of the global optimal performance, without requiring any access to route preview information. It was also shown that as much as 2.44% extra fuel savings could be achieved over a driving route, through the incorporation of route preview information into a real-time controller. Investigations were also made into the real-time fuel savings that could be realised over a driving route, through vehicle speed control. Results from these analyses show that, compared to an HEV technology which comes at a bigger cost, far higher fuel savings, as much as 45.96%, could be achieved through a simple real-time vehicle speed control approach.