The aim of this thesis is to investigate the Air Conditioning system in a heavy duty truck and to develop a control strategy for the case when low cooling capacity is needed from the AC-system. A model of the AC-system was developed in order for an efficient controller to be designed. The model was designed to comprise of all the basic behaviours that the AC- system has, rather than to be an exact model of the system. As the AC-system showed to be very complex, a number of limitations in the model had to be made. The AC-system has two temperature sensors and is actuated by turning the AC- compressor on or off. Two different control strategies were tested for the control of the AC-compressor. The first was to use a controller to directly control the compressor clutch and the second one utilised a pulswidth modulated control structure were the controller stated the pulswidth to be used. Both control structures were implemented in the computer model, the AC-rig and in a truck in a climate chamber. Both control strategies showed to fulfil the demands on the system in the somewhat idealistic circumstances during which they were tested.

Platooning has the potential to significantly reduce fuel consumption, but with heavy duty vehicles scattered on roads driving alone, there is a need for coordination. One solution is for a vehicle to increase its speed to catch up and platoon with a preceding vehicle. This could reduce the fuel consumption of a mission, but it could also increase it if too much fuel is spent catching up. By finding the fuel consumption of catching up and platooning and comparing it to driving alone the decision of whether or not to catch up can be made. This thesis proposes a fuel-optimal algorithm based on a look-ahead controller taking future road topography into account to find the optimal trajectory and merge point when catching up to a preceding vehicle. By weighting time against fuel in the objective function, the addition of a state to keep track of time can be avoided and thus the algorithm can remain low in complexity, making it suitable for dynamic programming (DP). The DP algorithm is iterated in a forward fashion keeping track of the time-to-come for each state until it catches up to the preceding vehicle, then the platooning is simulated with a constant time gap, making it easy and fast to simulate. The algorithm is tested on real-world road topography data where it showed that taking road topography into account when choosing the merge point can have a significant fuel reduction.

Freight transport demand has escalated and will continue to do so as economiesgrow. As the traffic intensity increases, the drivers are faced with increasinglycomplex tasks and traffic safety is a growing issue. Simultaneously, fossil fuel usageis escalating. Heavy duty vehicle (HDV) platooning is a plausible solution to theseissues. Even though there has been a need for introducing automated HDV platooningsystems for several years, they have only recently become possible to implement.Advancements in on-board and external technology have ushered in new possibilitiesto aid the driver and enhance the system performance. Each vehicle is able to serveas an information node through wireless communication; enabling a cooperativenetworked transportation system. Thereby, vehicles can semi-autonomously travel atshort intermediate spacings, effectively reducing congestion, relieving driver tension,improving fuel consumption and emissions without compromising safety. This thesis presents contributions to a framework for the design and implementation of HDV platooning. The focus lies mainly on establishing and validating realconstraints for fuel optimal control for platooning vehicles. Nonlinear and linearvehicle models are presented together with a system architecture, which dividesthe complex problem into manageable subsystems. The fuel reduction potentialis investigated through simulation models and experimental results derived fromstandard vehicles traveling on a Swedish highway. It is shown through analyticaland experimental results that it is favorable with respect to the fuel consumption tooperate the vehicles at a much shorter intermediate spacing than what is currentlydone in commercially available systems. The results show that a maximum fuelreduction of 4.7–7.7 % depending on the inter-vehicle time gap, at a set speedof 70 km/h, can be obtained without compromising safety. A systematic designmethodology for inter-vehicle distance control is presented based on linear quadraticregulators (LQRs). The structure of the controller feedback matrix can be tailoredto the locally available state information. The results show that a decentralizedcontroller gives good tracking performance, a robust system and lowers the controleffort downstream in the platoon. It is also shown that the design methodologyproduces a string stable system for an arbitrary number of vehicles in the platoon,if the vehicle configurations and the LQR weighting parameters are identical for theconsidered subsystems. With the results obtained in this thesis, it is argued that a vast fuel reductionpotential exists for HDV platooning. Present commercial systems can be enhancedsignificantly through the introduction of wireless communication and decentralizedoptimal control. / QC 20111012

Increasing demands for lower environmental impact from vehicles, including heavy-duty vehicles, have driven several vehicle manufacturers to consider adding hybrid electrical vehicles (HEV’s) to the product portfolio. Present research on batteries for HEV’s is mainly focused on lithium-ion battery chemistries, since lithium-ion batteries has the most promising technical potential compared to other types of batteries. However, the uncertainty regarding battery lifetime combined with a high battery cost can have a negative impact on large scale commercialisation of heavy-duty hybrid vehicles in the near future. A large part of present lithium-ion battery research is focused on new materials, but there is also research focusing on ageing of already established lithium-ion battery chemistries. Cycle ageing of batteries often includes complete charging and discharging of batteries or the use of standardized test cycles. Battery cycling in real HEV applications is however quite different compared to this kind of laboratory testing, and real life testing on vehicles is a way of verifying the soundness of laboratory ageing. The aim of this study was to develop a test method suitable for real life testing of lithium-ion batteries for heavy-duty HEV-usage, with the purpose of investigating the correlation of battery ageing and usage in real life applications. This concept study includes both cell level battery cycling and performance testing on board vehicles. The performance tests consist of discharge capacity measurements and hybrid pulse power characterization (HPPC) tests. The main feature of this test equipment is that it is designed to be used on conventional vehicles, emulating an HEV environment for the tested battery. The functionality of the equipment was verified on a heavy-duty HEV with satisfying results. Results from real life testing of 8 batteries using the developed test equipment on four conventional heavy-duty trucks shows that the concept of comparing battery ageing with battery usage has a most promising potential to be used as a tool when optimizing battery usage vs. lifetime. Initial results from this real life study shows significant differences in state of charge (SOC) and power distributions between cycled batteries, but so far only small differences in ageing. Lithium-ion batteries of the type lithium manganese spinel/lithium titanate (LMO/LTO) were used in this study. / Ökande krav på minskad miljöpåverkan från fordon, inklusive tunga fordon, har drivit flera fordonstillverkare till att addera hybridiserade fordon till produktportföljen. Forskning på hybridfordonsbatterier är idag huvudsakligen inriktad på litiumjonbatterikemier, vilken har den mest lovande tekniska potentialen jämfört med andra typer av batterikemier. Det finns idag en risk att osäkerheten kring litiumjonbatteriers livslängd i kombination med en hög batterikostnad kan ha en negativ inverkan på en storskalig kommersialisering av tunga hybridfordon inom den närmsta framtiden. En stor del av batteriforskningen är inriktad på nya material, men det finns även forskning som fokuserar på åldring av redan etablerade litiumjonbatterikemier. Vid åldringsprov används ofta standardiserade testcykler eller cykler där batterierna blir fullständigt laddade och urladdade. Cykling av batterier i verkliga förhållanden skiljer sig dock från den typen av laboratorietester och provning på fordon är därför ett sätt att kontrollera att laboratorieprovning ger relevanta resultat gällande åldring. Syftet med denna studie var att utveckla en testmetodik lämplig för provning av litiumjonbatterier för tunga hybridfordon i verklig drift, med syfte att undersöka kopplingen mellan batteriers åldrande och hur det används. Detta koncept inkluderar battericykling på cellnivå och möjligheten att utföra batteriprestandatester på fordon, där prestandatesterna består av kapacitetsprov och pulsprov. Den viktigaste egenskapen hos den utvecklade testmetodiken är att provning sker på konventionella fordon genom att emulera en hybridmiljö för det testade batteriet. Funktionaliteten hos den utvecklade testutrustningen verifierades på en tung hybridlastbil med goda resultat. Resultaten från en fältstudie av 8 batterier på 4 lastbilar där den utvecklade testutrustningen användes påvisar att testmetodiken har en lovande potential att kunna användas som ett verktyg vid optimering av utnyttjandegrad och livslängd för HEV-batterier. De initiala resultaten från denna fältstudie påvisar skillnader i laddningsgradsfördelning och batterieffektfördelning mellan cyklade batterier, men ännu bara små skillnader i åldring. Litiumjonbatterier av typen litiummanganspinel/litiumtitanat (LMO/LTO) användes i denna studie. / QC 20111205

Autonomous vehicles is a rapidly expanding field, and promise to play an important role in society. In more isolated environments, vehicle automation can bring significant efficiency and production benefits and it eliminates repetitive jobs that can lead to inattention and accidents. The thesis addresses the problem of lateral and longitudinal dynamics control of autonomous ground vehicles with the purpose of accurate and smooth path following. Clothoids are used in the design of optimal predictive controllers aimed at minimizing the lateral forces and jerks in the vehicle. First, a clothoid-based path sparsification algorithm is proposed to efficiently describe the reference path. This approach relies on a sparseness regularization technique such that a minimal number of clothoids is used to describe the reference path. Second, a clothoid-based model predictive controller (MPCC) is proposed. This controller aims at producing a smooth driving by taking advantage of the clothoid properties.  Third, we formulate the problem as an economic model predictive controller (EMPC). In EMPC the objective function contains an economic cost (here represented by comfort or smoothness), which is described by the second and first derivatives of the curvature.  Fourth, the generation of feasible speed profiles, and the longitudinal vehicle control for following these, is studied. The speed profile generation is formulated as an optimization problem with two contradictory objectives: to drive as fast as possible while accelerating as little as possible. The longitudinal controller is formulated in a similar way, but in a receding horizon fashion. The experimental evaluation with the EMPC demonstrates its good performance, since the deviation from the path never exceeds 30 cm and in average is 6 cm. In simulation, the EMPC and the MPCC are compared with a pure-pursuit controller (PPC) and a standard MPC. The EMPC clearly outperforms the PPC in terms of path accuracy and the standard MPC in terms of driving smoothness. / <p>QC 20160503</p> / iQMatic

Class 8 heavy-duty truck platooning has demonstrated significant fuel economy benefits on routes with road grade less than±2% in literature, but there is little to no platooning research on routes with road grade greater than±2% - which make up a significant portion of U.S. highways. Therefore, the effort described in this thesis is aimed at assessing currently available two-truck platoon control strategies as well as developing new strategies to improve platoon performance on hilly terrain. Specifically, the strategies tested in this work include four types of lead truck speed control strategies and two types of platoon transmission shifting strategies. These strategies are tested using two experimentally validated heavy-duty, two-truck platoon simulation approaches where each approach has its own advantages and disadvantages. The trends observed from these two simulation approaches indicate that the lead truck speed control and transmission shifting strategies have a significant effect on the platoon fuel economy and gap control performance when the platoon operates on a hilly terrain route.

Indiana University-Purdue University Indianapolis (IUPUI) / The identification of the vocation of an unknown heavy-duty vehicle is valuable to parts manufacturers who may not have otherwise access to this information on a consistent basis. This study proposes a methodology for vocation identification that is based on clustering techniques. Two clustering algorithms are considered: K-Means and Expectation Maximization. These algorithms are used to first construct the operating profile of each vocation from a set of vehicles with known vocations. The vocation of an unknown vehicle is then determined using different assignment methods. These methods fall under two main categories: one-versus-all and one-versus-one. The one-versus-all approach compares an unknown vehicle to all potential vocations. The one-versus-one approach compares the unknown vehicle to two vocations at a time in a tournament fashion. Two types of tournaments are investigated: round-robin and bracket. The accuracy and efficiency of each of the methods is evaluated using the NREL FleetDNA dataset. The study revealed that some of the vocations may have unique operating profiles and are therefore easily distinguishable from others. Other vocations, however, can have confounding profiles. This indicates that different vocations may benefit from profiles with varying number of clusters. Determining the optimal number of clusters for each vocation can not only improve the assignment accuracy, but also enhance the computational efficiency of the application. The optimal number of clusters for each vocation is determined using both static and dynamic techniques. Static approaches refer to methods that are completed prior to training and may require multiple iterations. Dynamic techniques involve clusters being split or removed during training. The results show that the accuracy of dynamic techniques is comparable to that of static approaches while benefiting from a reduced computational time.

Background: Climate changes and global warming call for behaviour changes from mankind and for new business models to introduce sustainable innovations. Financial analysis plays an important role in guiding the choice of these business models. However, assumptions and uncertainties pose challenges to the use of financial analysis in business modelling. Purpose: The purpose of this study is to develop a proactive systematic approach of financial analysis in business modelling. Accounting for the important role of assumptions and uncertainty factors, the approach should guide the choices of capital structure, revenue model, and strategic partnerships in the business model. Methodology: The developed approach combines the use of different methods to assess different business models for a public fast-charging stations for electric heavy-duty vehicles in Sweden. The used techniques are DCF analysis, What-If analysis, Tornado diagram, Monte-Carlo simulation, and multiple linear regression analysis. Results and analysis: Applied to the case of a public fast-charging station for electric heavy-duty vehicles, the approach leads to the identification of potential viable business models. Under the condition of using financial leverage through debt, additional revenue sources such as per-charge event user fee and advertising as well as partnership with the public sector in the form of grants, it is possible to achieve a viable business model. Conclusions: A systematic proactive approach of the use of financial analysis in business modelling was successfully developed and applied to the case of fast-charging stations for electric heavy-duty vehicles. The identified viable business models rely on financial leverage through debt, additional revenue sources and partnership with the public sector in the form of grants. Recommendations for future research: Simulations with more input parameters as well as combinations with observational studies of existing business models can be further investigated.

Fire Works is a cultural center that will seem durable, welcoming and useful. The Culture center will serve as an extension of the central fireplace in the building. Something that gives light and life to the city with the activity created by the presence of the citizens. The building remains within the framework of the environment that surrounds it, a million program area with material dominance of concrete, glass and steel. / Fire Works är ett kulturcenter som ska verka tåligt, välkomnande och användbart. Kulturhuset ska fungera som en förlängning av den centrala eldstaden i byggnaden. Något som ger ljus och liv åt staden med den aktivitet som skapas av människans närvaro. Byggnaden håller sig inom ramarna för den miljö som omger den, ett miljonprogramsområde med materiell dominans av betong, glas och stål.

Wading is the phenomenon where a vehicle drives through water with a relatively deep water level. Sincea large portion of the vehicle is submerged in water it can affect the driveability and function of individualcomponents. Wading is therefore an important phenomenon to be aware of especially today where society moves towards alternative energy sources. This includes water sensitive components when contact with water can generate major consequences. Previous knowledge and experience of wading has been from performing physical tests, but using Computational Fluid Dynamics (CFD) to examine the phenomenon can accelerate the iterative design process. In this thesis, numerical method of wading simulations on complete heavy-duty vehicles using the software STAR-CCM+ are developed. Furthermore, the results from the numerical methods are validated against results from physical tests performed at Scania’s test facility in Södertälje. The numerical methods are divided into a simplified model of a Battery Electric Vehicle (BEV) and a detailed geometry of a gas-driven vehicle from Scania. Beside dividing the wading scenario into the geometries, two different methods are developed, Wave and Wading. The Wave-method includes the vehicle standing still while a water wave is fed in through the inlet of the domain, i.e. allowed to flush over the vehicle, with a velocity of 3.6 km/h and 8 km/h. This method is implemented for both a generic simplified BEV truck and a detailed real-life Scania truck. For the Wading-method, motion is applied to the vehicle where itis driving with a velocity of 3.6 km/h through a digital twin of the water trench available at the test facility. This method is further divided into two cases, Zero Gap and Floating, where the difference is the distance between the tires of the vehicle and ground of the domain. The Floating-case includes a 10 cm distance and the Zero Gap-case has no gap between the tires and ground. The Wading-method is only implemented for the simplified geometry due to the computational cost and complexity. All methods use the Volume of Fluid (VOF) method for multiphase modelling and the Zero Gap-case uses Overset Mesh for modelling motion. The validation of the simulations focuses on the water behaviour such as water surface topology and water flowing inside the vehicle while wading. The results for the Wave-method with both the simplified and detailed truck at 8 km/h shows similarities in the water surface topology between the numerical model and the physical test. The simulations of the Wading-method is not visualising any similarities since the visible wave pattern are few and unclear in the numerical model. An isosurface is used to visualise the surface of the water which generated a smooth topology since no other options, such as vector fields, are added. It is found that the water movement inside the vehicle will affect water sensitive areas, e.g. on the battery packs. It is concluded that the derived methods are a first draft and should be directed towards future development in optimising the methods to lower the computational cost, but also to improve the capturing of the interface between the two phases. Due to instability and computational cost the detailed geometry is not implemented in the Wading-method. The methods are adapted to use different vehicle types since the simplified and detailed geometry are a BEV and a gas-driven truck respectively.