Background  Global warming caused by greenhouse gas emissions necessitates a decrease in carbon emission caused by the truck transport industry. To combat the threat of global warming, goals are being set up on a global, national and corporate level. These goals are putting pressure on logistics service providers to decrease the emissions within the truck transport industry. Implementation of green practices is found to be especially challenging within heavy truck transport due to weight and distance of the transport characteristics. In order to achieve emission reductions, logistics service providers are dependent on the alignment with their transport buyers, known as shippers to implement green logistics practices. Purpose The purpose of this study is to identify challenges and enablers for sustainable green transitions within heavy truck transports among shippers and logistics service providers. The study formulates two research question to help achieve the purpose, these questions are focused on challenges and enablers among both shippers and logistics service providers.  Method The study employs an explorative research approach in a multiple case study setting. Three configurations of shipper-LSP relationships are studied and analyzed through thematic analysis, the researchers also conducted a cross-case analysis to compare and identify similarities and differences between the cases in order to draw conclusions.  Conclusion A green transition within the heavy truck transport sector face numerous challenges. The challenges include a high dependency on vehicle development, lacking infrastructure, alignment issues between shippers and logistics service providers and trade off dilemmas. In order to overcome the issues findings, suggest that shippers and LSPs should focus on creating shared goals in order to facilitate implementation of green logistics practices and mitigate the challenges.

Kommersiella tunga transporter står för en stor del av utsläppen av växthusgaser. För att minska det globala fotavtrycket hos kommersiella fordon är det vanligt att använda biodrivmedel som ”drop in” bränslen. De avancerade motorer som för närvarande finns på marknaden är känsliga för olösliga föroreningarna, vilka benämns ”mjuka partiklar” av Scania. Dessa partiklar bildas som ett resultat av att biodieseln åldras, p.g.a. oxidationsinstabilitet, och en växelverkan med metalltillsatser i bränslet. Mjuka partiklar orsakar interna dieselinjektoravlagringar (IDID) och ett snabbt åldrande av bränslefilters genom igensättning. Avsikten med denna studie var att analysera det sistnämnda problemet genom att undersöka bränslefiltrets filtreringseffektivitet av oönskade mjuka partiklar. Ett protokoll över utförandet av feltreringstesterna utvecklades och skalades upp från en småskalig filterrestrigg vid KTH (Fas 1) till en fullskalig filtertestrigg på Scania (fas 2). Den experimentella uppställningen var ett försök att reproducera fältscenarier för filtrering i verkliga lastbilar. Tyngdpunkten i fas 1 riktades mot accelererade tester i den småskaliga testriggen med höga koncentrationer av tvålmjuka partiklar av zinkneodekanoat och syntetiskt producerade mjuka kalciumpartiklar. Separationseffektiviteten hos bränslefilter undersöktes med hjälp av GC-MS-analys. ICP mätningar gjordes för att upptäcka Zn2+ och Ca2+-joner i tvålämnena. Dessa tvålämnen identifierades tidigare på igensatta bränslefiltren och värden från dessa konventionella bränslefilter jämfördes med resultat från en absorptionsfiltreringsprocess med hjälp av ler(silikat)filter. Syftet med jämförelsen var att studera en alternativ bränslefiltreringsteknik för fordonstillämpningar. Mätningar med SEM-EDS gav rimliga förklaringar angående effektivitetsvärden för Zn-och Ca-tvålämnen för olika filtren, som används i försöken. Adsorptionsfiltret av lera hade 99 % filtreringseffektivitet och är en intressant lösning för framtida studier. Fas 2 fokuserade på en uppskalning av försöksprotokoll för filtreringstester med biobränslen och inkluderade sex olika riggförsök. Resultaten visade på tillförlitliga och exakta värden av tryckvariationer och filtereffektiviteten med en maximal effektivitet på 63,3 % för huvudfiltret och 75 % för förfiltret, som ett resultat av GC-MS-analysen. De uppmätta tryckvariationerna visar att förfiltret fångar in en majoritet (över 70 %) av de mjuka partiklarna, vilket resulterar i en ökning av tryckfallet över tiden. Med hänsyn till resultaten så rekommenderas försöksförfarandet för fortsatta framtida studier. / Commercial heavy duty transportation accounts for a major share of greenhouse gas emissions. In order to reduce the global footprint, commercial vehicles are widely known to use biodiesel as drop in fuels. The advanced engines, currently on the market, are sensitive to the insoluble contaminants, termed as soft particles in Scania. They are formed because of aging of biodiesel and the interaction with metal additives in the fuel. This is a common problem associated with the fuel due to high oxidation instability. Soft particles are responsible for causing Internal Diesel Injector Deposits (IDIDs) and premature fuel filter clogging. This report deals with the analysis of the latter problem. The purpose of the project is to investigate the fuel filter efficiencies against desired soft particles. A protocol of experiments was developed and scaled up from a small-scale filter rig at KTH (Phase 1) to a full-scale filter test rig at Scania (Phase 2) at ambient temperatures. The experimental campaign in this project is an attempt to replicate on field scenarios of filtration in real trucks. In Phase 1, the emphasis of the accelerated tests (higher concentrations) was on using soap soft particles, zinc neodecanoate and synthetically produced calcium soft particles for the small-scale filter rig. Separation efficiencies of fuel filters were examined using GC-MS analysis. Whereas ICP measurements were done to detect Zn2+ and Ca2+ ion in these soaps. These soaps were successfully identified to be present on the clogged fuel filters. Values from conventional fuel filters were compared with results from absorption filtration process using clay (silicate) filters. The purpose of the comparison was to study an alternate fuel filtration technique for vehicle application. Furthermore, SEM-EDS provided reasonable explanations about the efficiency values of the filters against Zn and Ca soaps used in the operation. The adsorption clay filter as had 99% of filtration efficiency proving an interesting solution for future investigations. Phase 2 started with an initiation of the scaling up or the protocol for test fuels, including six different rig operations. The maximum efficiencies of the filters (63.3% for main filters and 75% for pre filters) were noted as a result of quantification of the GC-MS results of the samples obtained from the rig. The pressure variations recorded proved, that the pre filters were trapping majority (over 70%) of the soft particles showing a rise in pressure drops over time. According to the results, the full-scale filter rig gave reliable and accurate values of pressure variations and filter efficiencies. Thus, it is suggested to use in the future investigations.

In line with the Paris agreement, Sweden has set up a national emission reduction target for the transport sector; to reduce the emissions by 70% by 2030, relative to levels in 2010. This entails that large shares of road transport will be electrified, including shares of the national truck fleet. In parallel with this, the Swedish transmission grid suffers from power capacity shortages, limiting the amount of electricity that can be distributed to a regional and local level, especially in urban areas, such as Stockholm. In line with this, the aim of this thesis is to investigate the trends of truck electrification in the Stockholm region and to assess its potential impact on the electrical grid based on truck operation characteristics. To achieve this, three objectives were set; to investigate truck fleet operators’ operations and view in relation to electrification, examine truck manufacturers' views on truck electrification and to analyse the truck electrification’s potential impact on the electrical grid in future scenarios. Quantitative and qualitative methods were used to fulfil the research objectives including interviews and casestudy modelling. The results from the interviews show that both manufacturers and truck fleet operators see the electrical grid and deployment of charging infrastructure, as well as the economy of the electric truck as the main barriers to overcome in relation to truck electrification. The truck manufacturers have taken on a leading role and are together with early adopters pushing the development forward. Nonetheless, they cannot create all the right conditions themselves, as for instance charging opportunities in relation to the electric grid is a complex problem. The industry agreed upon that city transports will be electrified first followed by regional transport and lastly long-distance transport. Furthermore, 2030 was identified as a key year for truck electrification. Finally, manufacturers and truck fleet operators urge the government to act and implement necessary measures to support the transition. The results from the case-study modelling show that lunchtime charging of city transport coincides with already critical hours for the electrical grid. Moreover, the afternoon charging of city, regional and long-distance transports generates a peak during the most critical hour around 6 PM, implying that it could entail challenges for an already congested grid. In line with this, proper night-time charging is considered as crucial both from an operational (in terms of minimising the daily stops) and grid point of view (in terms of avoiding grid congestion during critical hours). In addition, it is recommended to prioritise charging of long-distance transport during the day as they often are operative around-the-clock. Although this study resulted in general charging profiles, this gives a good indication on what impact the truck electrification might have on the electrical grid. Furthermore, it gives a general picture of how the electrification of trucks could play out in Stockholm, which can be applied in other urban areas in Sweden that are facing similar challenges. / I linje med Parisavtalet har Sverige satt upp nationella utsläpps reduktionsmål för transportsektorn; att reducera utsläppen med 70% till 2030, relativt nivåerna 2010. Detta medför att stora delar av transportsektorn kommer att elektrifieras, inklusive stora delar av den nationella lastbilsflottan. Parallellt med detta lider det svenska transmissionsnätet av kapacitetsbrist vilket begränsar mängden elektricitet som kan överföras till en regional och lokal nivå, speciellt i urbana områden såsom Stockholm. I linje med detta har syftet med denna studie varit att undersöka trender inom lastbils-elektrifiering i Stockholmsregionen och att utvärdera dess potentiella inverkan på elnätet baserat på lastbilars operativa mönster. För att uppnå detta sattes tre mål upp; att undersöka lastbils-operatörers verksamhets mönster och deras syn på elektrifiering, att undersöka lastbilstillverkares syn på elektrifiering och att analysera lastbils-elektrifieringens potentiella inverkan på energisystemet i framtida scenarier. Kvantitativa och kvalitativa metoder användes för att uppnå studiens mål inklusive; intervjuer och fallstudie modellering. Resultaten från intervjuerna visar att både lastbils-operatörer och tillverkare ser elnätet och utbredningen av laddinfrastruktur, såväl som totalekonomin av den elektriska lastbilen som de huvudsakliga barriärerna att överkomma vid en elektrifiering. Lastbilstillverkare har tagit en ledande roll och driver utvecklingen av elektriska lastbilar framåt med hjälp av så kallade early adopters. Däremot kan de inte skapa alla förutsättningar själva då till exempel laddnings möjligheter i relation till elnätet är en komplex fråga. Industrin är eniga om att city transporter kommer att elektrifieras först, följt av regionala och till sist fjärrtransporter. Vidare kunde 2030 identifieras som ett nyckelår för elektrifieringen. Slutligen uppmanar både tillverkare och lastbils operatörer regeringen att implementera nödvändiga åtgärder för att stötta och påskynda omställningen. Resultaten från modelleringen i fallstudien visar att lunch-laddning för city transporter sammanfaller med redan kritiska timmar för elnätet. Dessutom genererar eftermiddagsladdningen av city, regionala och fjärrtransporter, en effekttopp runt klockan 18 vilket skulle kunna medföra utmaningar för ett redan överbelastat elnät. I linje med detta anses natt-laddning vara avgörande både från en operativ synpunkt (i form av att minimera de dagliga stoppen) och från ett elnäts perspektiv (i form av att undvika överbelastning av nätet under redan kritiska timmar). Därtill, rekommenderas att fjärrtransporter prioriteras för dagtids-laddning då de ofta är operative dygnet runt. Trots att denna studie resulterade i generella ladd-profiler kan dessa ge en god indikation för vilken inverkan lastbils-elektrifieringen kan komma att ha på elnätet. Vidare, ger studien en generell bild över hur lastbils-elektrifieringen kan komma att se ut i Stockholmsregionen vilket kan tillämpas i andra urbana områden i Sverige som står inför liknande utmaningar.

The transport sector is facing great challenges for achieving development within the Earth’s boundaries. Currently, LCA studies on heavy- and medium-duty vehicles have mainly assessed the ‘well-to-wheel’ stage and the impact category climate change. To understand the full range of environmental impacts from a truck, a holistic view needs to be adopted, to acknowledge several sustainability dimensions. The development of new vehicle technologies, such as battery electrical vehicles (BEV), the impact will mainly occur in the production and end-of-life stage, thereby it is crucial to adapt a cradle-to-grave approach in LCA. This thesis have interpret Scania’s current LCA results through normalization and weighting. The normalization and weighting methods used have been based on the planetary boundaries (PBs) and other scientific thresholds of earth’s carrying capacity. The normalised results display that considering a heavy-duty truck with diesel (B5) climate change is the major impact, but for BEV with EU electricity mix it is freshwater ecotoxicity, stratospheric ozone formation and climate change that are the main impacts to consider. For the BEV with wind electricity, it is freshwater ecotoxicity and climate change which are the major impacts. According to the weighed results, the impact on ́climate change ́ and ́fossil resource scarcity ́ are most important for diesel (B5) and considering BEV with EU mix it is the impact categories of ́climate change ́ and ́fossil resource depletion ́ followed by ́mineral resource scarcity ́. Considering BEV with wind electricity it is ́mineral resource scarcity ́ followed by ́climate change ́ and ́fossil resource scarcity ́. The weighted results also display that the impact categories, ‘human toxicity cancer’, ‘freshwater ecotoxicity’, ‘particulate matter’ and ‘water resource scarcity’ are important to consider in an LCA of a BEV. Concludingly, it is a need for future research in the area of connecting the PBs with the LCA framework. Moreover, it is a need to develop normalisation reference (NR) and weighting factors (WF) based on a company and sectorial allowances of the carrying capacity to understand a product or company’s environmental impact in absolute terms. / Transportsektorn står inför stora utmaningar för att nå en utveckling inom planetens gränser. I nuläget har LCA studier för tunga och medeltunga transporter fokuserat på ‘well-to-wheel’ vilket är stegen bränsleproduktionen (från källan till tanken) och konsekvenserna av fordonets användning (från tank till hjul) och påverkanskategorin klimat. För att förstå fordonets totala miljöpåverkan, behövs ett holistiskt synsätt för att förstå flera hållbarhetsdimensioner av fordonets miljöpåverkan. Utvecklingen av nya fordonstekniker, så som batterifordon, kommer leda till att miljöpåverkan möjligen främst uppstår i produktions och avfallsfasen av livscykeln, det är därav viktigt att analysera ett fordon från ́vaggan till graven ́. Denna uppsats har analyserat Scanias LCA resultat genom normalisering och viktning. Normaliserings- och viktningsmetoderna som används är baserade på dom planetära gränserna och andra tröskelvärden för planetens bärkapacitet. Det normaliserade resultatet visar att för en diesel lastbil är klimat en betydande påverkanskategori, dock för en BEV (”Battery Electric Vehicle”) med EU elektricitet är det sötvattentoxicitet, stratosfärisk ozonbildning och klimat som är dom mest betydande påverkanskategorierna. Det normaliserade resultatet för BEV med vindenergi visar att det är sötvattentoxicitet och klimat som dom mest betydande påverkanskategorierna. Enligt den valda viktningsmetoden framgår det att klimat och fossil resursutarmning är dom viktigaste påverkanskategorierna för en diesel lastbil. För en BEV med EU mix är den viktigaste klimat och fossil resursutarmning följt av mineralresursbrist. För BEV laddad med energi från vindkraft, är dom viktigaste påverkanskategorierna mineralresursbrist, klimat och fossil resursutarmning. Det viktade resultatet visade även att påverkanskategorierna, humantoxicitet cancer, sötvatten ekotoxicitet, partiklar och vattenresursbrist bör tas i beaktning i en LCA av en BEV. Slutligen behövs det mer forskning kring sammankoppling av planetära gränser och LCA ramverket, även utveckling av normaliseringsreferenser och viktningsfaktorer som är baserat på företags- och sektorsnivåer för utsläppsrätter behövs för att ett företag ska förstå produkters absoluta miljöpåverkan.

Hitachi Energy, one of the largest transformer manufacturers in the world, has a factory based in the small town of Ludvika, Sweden. Here, all of the production is carried out, from order to delivery, and the key to reaching the rest of the world lies within the Swedish railway network. Utilizing specialized railway wagons, Hitachi Energy transports the transformers to the industrial ports for further export to the rest of the world. To ensure safe transportation, with loads exceeding 400 tons, transportation consoles made for this exact purpose are used to carry the transformer's weight and keep them in place during transportation. However, with their current solution having stayed the same for many years, they now aspire to a new solution for the transportation consoles to fulfill both the physical and human-centered demands better. In this master's thesis, in industrial design engineering, a new solution for transportation consoles is being developed. To ensure the quality of the project, a design process with four stages - a learning phase, an ideation phase, a development phase, and a delivery phase - has been used. Three research questions have been in focus during the project:  What are the needs and requirements for the new transportation console? How can we identify both user needs and product requirements for the new transportation consoles through an industrial design engineering approach? How would a completely new solution for transportation consoles be designed and used in detail?  Several industrial design methods have been utilized in these phases to gain a broad knowledge of the problem and generate ideas. A product cycle analysis was conducted based on interviews and observations to better understand the product. When the knowledge was gathered, several brainstorming methods, scamper, and virtual prototyping were used to generate several new solutions and ideas. To test and develop the concepts in detail, computer-aided engineering has been used, with computer-aided design to virtually prototype the concepts and finite element analysis to verify them. The learning phase showed the need for a more user-friendly solution and how a slimmer console profile could improve the workers' overall experience. Multiple concepts of solving these problems in different ways were found in the ideation phase. After design reviews with the stakeholders and consultation with the supervisors, a final concept, Arc, for a new transportation console was chosen to continue with into the two later stages of the process. Arc's foundation lies within a human-centered design and the people interacting with it weekly. It has several advantages compared to the previous design, with its adjustability and slim design facilitating the workload and enabling easier transportation. Analyses of its durability against external accelerations have been conducted, leaning towards a promising outcome. However, further testing and verifications are needed to ensure its durability before use.

To reach the 1.5°C-goal of the Paris Agreement, all sectors have to be involved in the transition. The transport sector poses a considerable challenge regarding sustainable development and, within the sector, road transport contributes to the largest part of emissions in the EU. The development of fuels for heavy-duty vehicles is not as fast as for other types of vehicles. However, approaches combining biomethane and green hydrogen as alternative fuels have gained interest. There are plans to both expand the biogas sector and implementing hydrogen production on Gotland. Therefore, this study examines how two of these approaches, hythane and power-to-methane technology, compare to each other as HDV-fuels on Gotland. A simplified MCA has been conducted to compare the two alternative fuels’ performance against each other based on several criteria. The results show that hythane performed better than power-to-methane in the criteria categories technical performance and feasibility Gotland, while power-to-methane performed better regarding environmental impact. As hythane performed better in a larger number of criteria than biomethane produced through power-to-methane, the results of the study imply that, based on Gotland’s pre-conditions, hythane is preferable as HDV-fuel over using power-to-methane technology. However, prioritization of the criteria is not conducted and further research that includes weighing of the criteria, as well as examines the economic and social factors of the two systems, is required for a sufficient feasibility study.

The diesel engine in heavy-duty trucks is a complex system with many components working together, and a malfunction in any of these components can impact engine performance and result in increased emissions. Fault detection and diagnosis have therefore become essential in modern vehicles, ensuring optimal performance and compliance with progressively stricter legal requirements. One of the most common faults in a diesel engineis faulty injectors, which can lead to fluctuations in the amount of fuel injected. Detecting these issues is crucial, prompting a growing interest in exploring additional signals beyond the currently used signal to enhance the performance and robustness of diagnosing this fault. In this work, an investigation was conducted to identify signals that correlate with faulty injectors causing over- and underfueling. It was found that the NOx, O2, and exhaust pressure signals are sensitive to this fault and could potentially serve as additional diagnostic signals. With these signals, two different diagnostic methods were evaluated to assess their effectiveness in detecting injector faults. The methods evaluated were data-driven residuals and Random Forest classifier. The data-driven residuals, when combined with the CUSUM algorithm, demonstrated promising results in detecting faulty injectors. The O2 signal proved effective in identifying both fault instances, while NOx and exhaust pressure were more effective at detecting overfueling. The Random Forest classifier also showed good performance in detecting both over- and underfueling. However, it was observed that using a classifier requires more extensive data preprocessing. Two preprocessing methods were employed: integrating previous measurements and calculating statistical measures over a defined time span. Both methods showed promising results, with the latter proving to be the better choice. Additionally, the generalization capabilities of these methods across different operating conditions were evaluated. It was demonstrated thatthe data-driven residuals yielded better results compared to the classifier, which requiredtraining on new cases to perform effectively.

An operating vehicle requires energy to oppose the subjected driving resistances. This energy is supplied via the fuel combustion in the engine. Decreasing the opposing driving resistances for an operating vehicle increases its fuel efficiency: an effect which is highly valued in today’s industry, both from an environmental and economical point of view. Therefore a lot of progress has been made during recent years in the area of fuel efficient vehicles, even though some driving resistances still rises perplexity. These resistances are the air drag Fd generated by the viscous air opposing the vehicles propulsion and the rolling resistance Frr generated mainly by the hysteresis caused by the deformation cycle of the viscoelastic pneumatic tires. The energy losses associated with the air drag and rolling resistance account for the majority of the driving resistances facing an operating vehicle, and depends on numerous stochastic and ambient parameters, some of which are highly correlated both within and between the two resistances. To increase the understanding of the driving mechanics behind the energy losses associated with the complexity that is rolling resistance, a set of complete vehicle tests has been carried out. These tests were carried out on the test track Malmby Fairground, using a Scania CV AB developed R440 truck equipped with various sensors connected in one measurement system. Under certain conditions, these parameters can allow for an investigation of the rolling resistance, and a separation of the rolling resistance and air drag via explicit subtraction of the air drag from the measured traction force. This method is possible since the aerodynamic property AHDVCd(β) to some extent can be generated from wind tunnel tests and CFD simulations. Two measurement series that enable the above formulated method of separation were designed and carried out, using two separate measurement methods. One which enables the investigation of the transient nature of rolling resistance as it strives for stationarity, where the vehicle is operated under constant velocities i.e. no acceleration, and one using the well established method of coastdown, where no driving torque is applied. The drive cycles spanned a range of velocities, which allowed for dynamic and stationary analyses of both the tire temperature- and the velocity dependence of rolling resistance. When analysing the results of the transient analysis, a strong dependence upon tire temperature for given constant low velocity i.e. v ≤ 60 kmh−1 was clearly visible. The indicated dependency showed that the rolling resistance decreased as the tire temperature increased over time at a given velocity, and vice versa, towards a stationary temperature and thereby rolling resistance. The tire temperature evolution from one constant velocity to another, took place well within 50 min to a somewhat stationary value. However, even though the tire temperature had reached stationarity, rolling resistance did not; there seemed to be a delay between stationary tire temperature, and rolling resistance. The results did not indicate any clear trends for v ≥ 60 kmh−1, where the results at v = 80 kmh−1 were chaotic. This suggests that some additional forces were uncompensated for, or that the compensation for air drag was somehow wrongly treated at higher velocities. Several factors ruled out any attempts at proposing a new rolling resistance model. These included: the chaotic results for v = 80 kmh−1, the delayed rolling resistance response upon tire temperature stabilization, and the lack of literature support for the observed tendency. The results from the coastdown series on the other hand, showed good agreement with a dynamical model suggested in literature. The stationary temperature behaviour for the considered velocity range at assumed constant condition is also supported in literature. Finally, an investigation of the aerodynamic property AHDVCd inspired by ongoing work in ACEA (European Automobile Manufacturers’ Association), was carried out assuming both zero and non-zero air drag at low velocities. The results indicated surprisingly good agreement with wind tunnel measurements, especially when neglecting air drag at low velocities: as suggested by ACEA. / För att övervinna de motstånd som ett fordon utsätts för under drift krävs energi, vilket levereras genom förbränningen av bränsle. Genom att minska de körmotstånd som ett fordon utsätts för under drift, kan man öka dess energieffektivitet. Denna potential är idag högt värderad i fordonsindustrin, både ur ett miljömässigt och ekonomiskt perspektiv. På senare år har stora framsteg gjorts inom området energieffektiva fordon, men fortfarande råder det förvirring kring de energiförluster som förknippas med luftmotstånd Fd och rullmotstånd Frr, där luftmotståndet skapas av den omkringliggande viskösa luften, medan rullmotståndet genereras av hysteresen som uppstår när fordonets viskoelastiska pneumatiska däck utsätts för deformation. De energiförluster som förknippas med luft- och rullmotstånd motsvarar den största delen av de motstånd som ett fordon påverkas av, och beror på en mängd stokastiska och yttre parametrar, varav vissa är starkt korrelerade både inom och mellan nämnda motstånd. För att förbättra förståelsen kring dessa energiförluster, med fokus på förståelsen av rullmotstånd, har ett antal helfordonstest genomförts. Dessa genomfördes på provbanan Malmby Fairground med en R440 lastbil från Scania CV AB, utrustad med en mängd sensorer sammankopplade i ett mätsystem. Det uppbyggda mätsystemet möjliggjorde samtida mätningar av bl.a. drivande moment, motorvarv, fordonshastighet, däcktemperatur, omkringliggande lufts hastighet och dess riktning. Under specifika förhållanden kunde dessa parametrar möjliggöra analys av rullmotstånd genom en explicit subtraktion av luftmotstånd från den uppmätta drivande kraften. Denna metod är möjlig tack vare en förhållandevis bra modell av ekipagets aerodynamiska egenskap AHDVCd(β), som generats från vindtunneltest och CFD simuleringar. Två körcykler som möjliggjorde ovan formulerade separation designades och genomfördes. Dessa använder två skilda mätmetoder, varav den ena möjliggör analys av rullmotståndets övergående förlopp från dynamiskt till stationärt genom att hålla konstant hastighet. Den andra studerade det dynamiska förloppet genom den väletablerade metoden utrullning, dvs. utan något drivande moment. Dessa körcyklar genomfördes, för ett antal hastigheter, vilket möjliggjorde analys av både hastighets- och däcktemperaturberoendet hos rullmotstånd, under dynamiska såväl som stationära förlopp. Analysen av rullmotståndets dynamik i strävan mot stationära förhållanden visade på ett starkt temperaturberoende vid låga hastigheter dvs. v ≤ 60 kmh−1. Beroendet visade på att rullmotståndet avtog med ökande däcktemperatur och vice versa, tills dess att en någorlunda stationär temperatur för given hastighet uppnåtts. Däcktemperaturen stabiliserades till ett nytt stationärt värde inom 50 min från att hastigheten ändrats. Resultaten tyder dock på att även om stationär däcktemperatur uppnåtts finns det en fördröjning i rullmotståndets tidsspann innan rullmotståndet stabiliserat sig. För högre hastigheter, dvs. v ≥ 60 kmh-1, var dock inga klara trender synliga, varken i hastighet eller temperatur och resultaten vid v = 80 kmh-1 var kaotiska. Detta antyder att man missat att kompensera för någon kraft vid höga hastigheter, alternativt att man på något sätt kompenserar fel för luftmotståndet vid högre hastigheter. Flera faktorer hindrade försök att föreslå någon ny rullmotståndsmodell. Dessa faktorer inkluderar det kaotiska resultatet vid v = 80 kmh-1, tidsfördröjningen mellan stationärt rullmotstånd och däcktemperatur samt att resultatet för antagna stationära värden inte finner stöd i litteraturen. Resultatet från utrullningsprovet överstämmer dock bra med tidigare föreslagen dynamisk modell, samt att resultaten av beteendet hos stationär temperatur för olika hastigheter även de överensstämmer med och finner stöd i litteraturen. Slutligen har en studie kring den aerodynamiska egenskapen AHDVCd, inspirerad av pågående arbete inom ACEA (European Automobile Manufacturers’ Association) utförts både med antagandet av ett noll- skilt och med ett försumbart luftmotstånd vid låga hastigheter. Resultatet visar på en överraskande god överensstämmelse med vindtunnelmätningar, framför allt under antagandet av försumbart luftmotstånd vid låga hastigheter i enlighet med förslagen metod från ACEA.

Abstract Although researchers have studied the effects of platooning, most of the work done so far has focused on fuel consumption. There are a few studies that have targeted the impact of platooning on the highway operations and safety. This thesis focuses on the impact of heavy-duty vehicles (HDVs) platooning on highway characteristics. Specifically, this study aims at evaluating the effects of platooning of HDVs on capacity, safety, and CO2 emissions. This study is based on a hypothetical model that was created using the VISSIM software. VISSIM is a powerful simulation software designed to mimic the field traffic flow conditions. For model validity, the model outputs were compared with recommended values from guidelines such as the Highway Capacity Manual (HCM) (Transportation Research Board, 2016). VISSIM was used to obtain the simulation results regarding capacity. However, in addition to VISSIM, two other software packages were used to obtain outputs that cannot be assessed in VISSIM. MOVES and SSAM are two simulation software packages that were used for emission and safety metrics, respectively. Both software packages depended on input from VISSIM for analysis. It was found that with the presence of HDVs in the model, the capacity, the emission of CO2, and the safety of the roadway would improve positively. A capacity of 4200 PCE/h/ln could be achieved when there are enough HDVs in platoons. Furthermore, more than 3% of the traffic flow emission of CO2 reduction is possible when 100% of the HDVs used in the model are in platoons. In addition to that, a reduction of more than 75% of the total number of conflicts might be obtained. Furthermore, with the analysis of the full factorial method and the Design of Experiment (DOE) conducted by using Excel and Minitab respectively, it was possible to investigate the impact of the platoons’ factors on the highway parameters. Most of these factors affect the parameters significantly. However, the change in the desired speed was found to insignificantly affect the highway parameters, due to the high penetration rate. Keywords: VISSIM, MOVES, SSAM, COM-interface, HDVs, Platooning, Number of Conflicts

Le monde industriel, et en particulier l’industrie automobile, cherche à représenter au mieux le réel pour concevoir des outils et produits les plus adaptés aux enjeux et marchés actuels. Dans cette optique, le groupe Volvo a développé de puissants outils pour la simulation de la dynamique des véhicules industriels. Ces outils permettent notamment l’optimisation de composants véhicules ou de stratégies de contrôle. De nombreuses activités de recherche portent sur des technologies innovantes permettant de réduire la consommation des véhicules industriels et d’accroitre la sécurité de leurs usages dans différents environnements. En particulier, le développement des systèmes d’aide à la conduite automobile ITS et ADAS. Afin de pouvoir développer ces systèmes, un environnement de simulation permettant de prendre en compte les différents facteurs pouvant influencer la conduite d’un véhicule doit être mis en place. L’étude se concentre sur la simulation de l’environnement du véhicule et des interactions entre le véhicule et son environnement direct, i.e. le véhicule qui le précède. Les interactions entre le véhicule étudié et le véhicule qui le précède sont modélisées à l’aide de modèles mathématiques, nommés lois de poursuites. De nombreux modèles existent dans la littérature mais peu concernent le comportement des véhicules industriels. Une étude détaillée de ces modèles et des méthodes de calage est réalisée. L’environnement du véhicule peut être représenté par deux catégories de paramètres : statiques (intersections, nombre de voies…) et dynamiques (état du réseau). A partir d’une base de données de trajets usuels, ces paramètres sont calculés, puis utilisés pour générer de manière automatisée des scénarios de simulation réalistes. / The industrial world, and in particular the automotive industry, is seeking to best represent the real world in order to design tools and products that are best adapted to current challenges and markets, by reducing development times and prototyping costs. With this in mind, the Volvo Group has developed powerful tools to simulate the dynamics of industrial vehicles. These tools allow the optimization of vehicle components or control strategies. Many research activities focus on innovative technologies to reduce the consumption of industrial vehicles and increase the safety of their use in different environments. Particularly, the development of ITS and ADAS is booming. In order to be able to develop these systems, a simulation environment must be set up to take into account the various factors that can influence the driving of a vehicle. The work focuses on simulating the vehicle environment and the interactions between the vehicle and its direct environment, i.e. the vehicle in front of it. The interactions between the vehicle under study and the vehicle in front of it are modelled using mathematical models, called car-following models. Many models exist in the literature, but few of them deals specifically with heavy duty vehicles. A specific focus on these models and their calibration is realized. The vehicle environment can be represented by two categories of parameters: static (intersections, number of lanes) and dynamic parameters (state of the network). From a database of usuals roads, these parameters are computed, then, they are used to automatically generate realist traffic simulation scenarios.