Dissertations / Theses on the topic 'Heavy Duty Truck Industry'

Research shows that climate changes we face today is a consequence of the increasing amounts of greenhouse gases that circulate in our atmosphere due to increased human industrial activity. Many firms and industries are therefore increasingly implementing environmental management strategies to reduce greenhouse gas emissions towards a more sustainable environment. These environmental management efforts can be broadly classified under two umbrellas which are sustainable production and sustainable consumption and these two parts need to work together in order to contribute effectively towards a more sustainable environment. The environmental management literature however reveals a gap between sustainable production and sustainable use of vehicles in the automotive industry showing that while the major global environmental impact - greenhouse gas emissions - occurs when vehicles are put to use, the environmental management efforts in the industry are skewed to the production of vehicles.An emerging trend to breach this gap is that vehicle manufacturers are providing extending services to help vehicle users minimize their greenhouse gas emissions. This study analyses the extended service packages of the global truck manufacturer, Scania, against the environmental objectives and initiatives of five road transport companies in Sweden. An exploratory case study approach was used from the perspective of the road freight transport companies to find out if extended services present suitable opportunities to extend environmental management from manufacturers to users in the road freight transport industry. The study found that the extended services provide solutions that help road freighttransport companies to achieve lower fuel consumption and lower emissions from theirvehicles. Road freight transport companies traditionally invest in environmental initiatives to gain marketing advantages but the extended services present a rare opportunity to the companies to compete on profit margins by investing in the extended services.
Market Making of a High-value Business Model in Low Cost Markets: Value Co-Creation in Swedish Industry, CeLS, Project manager: Leif-Magnus Jensen, leif-magnus.jensen@jibs.hj.se, +46 36 10 1881.

Scania CV AB is a leading company within development and production of buses, trucks as well as industrial and marine engines. New environmental and safety legislations continuously demand higher quality from the products. An upcoming European legislation, Euro 6, implies that gas leakages from truck engines should be detected while driving. If the source of the leakage is not only detected, but also isolated, that is separated from other faults, the adjustments in the workshop goes faster since there is no need for leakage localisation. A faster reparation increases the up-time, i.e. the amount of time that the truck can be used. This master thesis work uses current methods developed at Scania for residual generation to perform model-based leakage diagnosis. In this work, measurements are gathered for dierent sensor faults and two leakages. The measurements are used to evaluate the actual performance of the resulting diagnosis system. The result, based on the residuals generated by the method, shows that leakages on the boost-side and the exhaust-side can be detected, and isolated from faults in the pressure sensors on the boost-side and the exhaust-side. The isolation of these four faults is considered the hardest to achieve among sensor faults and leakages why the full isolation performance is promising. Further measurements are needed to determine the full isolation performance of the diagnosis system. The resulting system is reasoned to be suitable for execution in real time on-board the truck.
Scania CV AB är en ledande koncern inom utveckling och produktion av bussar, lastbilar samt industri- och marinmotorer. Nya lagkrav för miljö och säkerhet ställer ständigt högre krav på de tillverkade produkterna. Ett nära förestående lagkrav för lastbilar, Euro 6, innebär att gasläckage från motorn ska detekteras under körning. Om läckaget förutom att detekteras också kan isoleras, det vill säga särskiljas från andra fel, går reparationen i verkstaden snabbare då man slipper lokalisera läckaget. En snabbare reparation ökar up-time, det vill säga tiden som lastbilen kan användas på åkeriet. I detta exjobb används befintliga metoder för residualgenerering framtagna på Scania för att åstadkomma modelbaserad läckagediagnos. Arbetet tar även fram mätdata för olika givarfel samt för två läckage i motorn. Denna mätdata används för att utvärdera det erhållna diagnossystemets faktiska prestanda. Resultatet, som bygger på residualerna som metoden genererat, visar att läckage går att detektera, och att läckagen går att isolera från fel på tryckgivarsensorer på laddluftssidan och avgassidan. Denna isolering anses vara den svåraste att uppnå av alla sensorfel samt läckage varvid övrig isoleringsprestande verkar lovande. Däremot behövs mer mätdata för att säkert kunna fastställa övrig isoleringsprestanda. Diagnosmetoden lämpar sig troligen för exekvering i realtid ombord på lastbilen.

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.

QC 20160503

iQMatic

Heavy-duty trucks accounts for 25% CO2 emissions in Sweden and there is approximately 12.6 million heavy-duty vehicles in the EU with different types of fuel and utilization areas. EU is implementing increased legislations to reduce emissions and increase the use of biofuel and members of the EU is starting to ban the use of diesel trucks in local areas, which drives the need to find other suitable fuel. Therefore, to study and compare the emissions and energy demand in the heavy-duty truck industry a case study is created. Which focuses on production and processing, transportation, distribution and fuel consumption. Cultivation of maize and anaerobic digestion of maize, waste and manure is included as well. Data gathered from the collaboration between the European Commission’s Joint Research Centre, eucar and Concawe (JEC) is used to create scenarios and these are validated with previous studies. The case study includes seven LNG cases, three LBG cases and two diesel cases together with several other cases collected for verification. Furthermore, potential boil-off and leakage during maintenance is included to further estimate the possible emissions correlated with LNG and LBG vehicles. The Well-to-Wheels analysis resulted in most LNG and LBG cases having higher energy input compared to diesel. LBG has the lowest emissions of greenhouse gases. The transportation method and distance are the most important aspects for the Well-to-Tank analysis. The fuel consumption is the main source of emissions and energy input in the Tankto-Wheels analysis. In conclusion, the transportation and fuel consumption are the greatest contributors of emissions and energy demand in the complete Well-to-Wheels analysis.

In an automated manual transmission it is desired to have zero torque in the transmission when disengaging a gear. This minimizes the oscillations in the driveline which increases the comfort and makes the speed synchronization easier. The automated manual transmission system in a Scania truck, called Opticruise, uses engine torque control to achieve zero torque in the transmission.In this thesis different control strategies for engine torque control are proposed in order to minimize the oscillations in the driveline and increase the comfort during a gear shift. A model of the driveline is developed in order to evaluate the control strategies. The main focus was to develop controllers that are easy to implement and that are robust enough to be used in different driveline configurations. This means that model dependent control strategies are not considered.A control strategy with a combination of a feedback from the speed difference between the output shaft speed and the wheel speed, and a feedforward with a linear ramp, showed very good performance in both simulations and tests in trucks. The amplitude of the oscillations in the output shaft speed after neutralengagement are halved compared to the results from the existing method in Scania trucks. The new concept is also more robust against initial conditions and time delay estimations.

Pricing of repair and maintenance (R&M) contracts is one among the most important processes carried out at Scania. Predictions of repair costs at Scania are carried out using experience-based prediction methods which do not involve statistical methods for the computation of average repair costs for contracts terminated in the recent past. This method is difficult to apply for a reference population of rigid Scania trucks. Hence, the purpose of this study is to perform suitable statistical modelling to predict repair costs of four variants of rigid Scania trucks. The study gathers repair data from multiple sources and performs feature selection using the Akaike Information Criterion (AIC) to extract the most significant features that influence repair costs corresponding to each truck variant. The study proved to show that the inclusion of operational features as a factor could further influence the pricing of contracts. The hurdle Gamma model, which is widely used to handle zero inflations in Generalized Linear Models (GLMs), is used to train the data which consists of numerous zero and non-zero values. Due to the inherent hierarchical structure within the data expressed by individual chassis, a hierarchical hurdle Gamma model is also implemented. These two statistical models are found to perform much better than the experience-based prediction method. This evaluation is done using the mean absolute error (MAE) and root mean square error (RMSE) statistics. A final model comparison is conducted using the AIC to draw conclusions based on the goodness of fit and predictive performance of the two statistical models. On assessing the models using these statistics, the hierarchical hurdle Gamma model was found to perform predictions the best

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.

Chinese heavy truck industry has witnessed an unprecedentedprosper since 2009, and it has been attracting an increasing number of westernheavy truck companies to conduct business activities. However, differentindustry environment has brought different situation including the government’spolicies and consumers’ buying habits for local companies and foreign competitors.Thus, this study aims to analyze the impact of industry factors in Chinese heavy truck industry by examining a collection of the methodology. Porter diamond model is widely applied to investigate industry’s competitive advantages, butit should be noted that in this research the model is adapted into a new version in light of the necessity of emphasizing Chinese government in businessactivities. Main findings of this study are as follows: (1) research andanalysis factors of impact Chinese heavy truck industry and highlight government’s influence as a significant impact factor through a series ofpolicies; (2) it might be of considerable benefit if foreign heavy truckcorporation can observe the political transformation or policies while setting themarketing strategy in China.

Thesis (Ph. D.)--University of California, Davis, 2004.
Degree granted in Civil and Environmental Engineering. Includes bibliographical references. Also available online. (Restricted to UC campuses)

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

An embedded model predictive controller for velocity control of trucks is developed and tested. By using a simple model of a heavy duty vehicle and knowledge about the slope of the road ahead, the fuel consumption while traveling near a set speed is diminished by almost 1% on an example road compared to a rule based speed control system. The problem is formulated as a look-ahead optimization problem were fuel consumption and total trip time have to be minimized. To find the optimal solution dynamic programming is used, and the whole code is designed to run on a Scania gearbox ECU in parallel with all the current software. Simulations were executed in a Simulink environment, and two test rides were performed on the E4 motorway.
En algoritm för hastighetsstyrning baserad på modell-prediktiv reglering har utvecklats och testats på befintlig styrsystem i ett Scania lastbil. Genom att använda en enkel modell av fordonet och kunskap om lutningen på vägen framför den kunde man sänka bränsleförbrukningen med nästan 1% i vissa sträckor, jämfört med en regelbaserad farthållare. Problemet är formulerat som en optimerings-problem där bränsleförbrukning och total restid måste minimeras. För att hitta den optimala lösningen användes dynamisk programmering och hela koden är skriven så att den kan exekveras på en Scania styrenehet. Koden är kan köras parallellt med den mjukvara som är installerad på styrenheten. Simuleringar utfördes i en miljö utvecklad i Simulink. Två test-körningar på E4 motorvägen utfördes.

Norway has already an almost emission-free power production and its sales of zero-emission light-duty vehicles surpassed 30% in 2018; a natural next challenge is to identify ways to reduce emissions of heavyduty vehicles. In this work the possibilities to deploy Fuel Cell Electric Trucks (FCET) on the route Oslo-Trondheim are analyzed by doing a techno-economic analysis. The literature study identified that in average 932 kton goods where transported between the cities. The preferred road choice goes through Østerdalen and that an average load for a long-distance truck is 16 tons. The methodology used in the study is based on cost curves for both truck and infrastructure, and a case study with various scenarios is evaluated to find a profitable business case for both an FCET fleet and its infrastructure. The cost curves for trucks are based on total cost of ownership (TCO) as a function of hydrogen price, while the levelized cost of hydrogen (LCOH) is used to present the cost of infrastructure. An analysis was made to identify the trucks component sizes and a FCET for this route would require an onboard hydrogen storage of 46 kg, a fuel cell stack with a nominal power of 200 kW, a battery of 100 kWh (min SOC 22%), and an electric motor with a rated power of 402 kW. TCO was calculated both for an FCET based on the dimensioned components and a biodiesel truck. The results show that an FCET purchased in 2020 can be competitive with biodiesel with a hydrogen price of 38.6 NOK/kgH2. While the hydrogen price can increase to 71.8 NOK/ kgH2 if the FCET is purchased in 2030. To identify the most suitable infrastructure, four different designs of hydrogen refueling stations (HRS) were compared. Furthermore, hydrogen production units (HPUs) with both alkaline or PEM type water electrolyzer were compared. The analysis in this study showed that the most cost competitive option was a 350-bar HRS without cooling, which only can serve type III onboard storage tanks. A HPU with alkaline electrolyzer was the most price competitive alternative. In case each HRS is refueling more than 7 FCETs per day, an HPU in direct connection to HRS is the preferred infrastructure setup. Three HRS are required along the route to ensure a minimum service level for the FCETs. When the TCO of the fuel cell truck and LCOH of the hydrogen infrastructure were compared for a 2020 scenario, no feasible solution was identified. The cost of installing three HRS in 2020, serving a fleet of 14-24 trucks, would cost 16.0 – 17.6 million NOK/year more than a fleet based on biodiesel trucks. In a future scenario, where both the FCET and infrastructure costs decrease due to expected learning curves, a business case can be found if at least 5 FCETs were refueling at each HRS on daily basis, which corresponds to a total fleet of approx. 24 FCETs. Finally, a set of clear recommendations on how to improve the techno-economic analysis in future studies are provided. Both by identifying areas lacking sufficient documentation and by providing steps how the tecno-economic model could be enhanced.
Norge har redan en nästintill utsläppsfri elproduktion och nollutsläppsbilar stod för mer än 30% av nybilsförsäljningen under år 2018. En naturlig nästa utmaning är att finna sätt att minska utsläpp från lastbilar. I detta examensarbete analyseras möjligheterna att introducera bränslecellslastbilar (FCET) efter dess engelska förkortning) på sträckan Oslo - Trondheim genom att göra en teknisk-ekonomisk bedömning. Litteraturstudien visade att i genomsnitt 932 kton gods fraktas mellan städerna, att vägen genom Østerdalen är att föredra och att genomsnittlig last för en långtradare är 16 ton. Arbetets metod bygger på att identifiera kostnadskurvor för både lastbilar och infrastruktur. Dessa kurvor kombineras i olika scenarier för att finna omständigheter där både en FCET-flotta och dess infrastruktur är lönsamma. Kostnadskurvorna för lastbilar baseras på den totala ägandekostnaden (TCO) efter dess engelska förkortning) som en funktion av vätgaspriset, medan den utjämnade kostnaden för vätgas (LCOH) efter dess engelska förkortning) används för att presentera kostnaden för infrastruktur. En analys gjordes för att finna passande storlek på FCET drivlina. För den specifika sträckan krävs en hydrogentank på 46 kg, en bränslecellstack med nominell effekt på 200 kW, ett batteri på 100 kWh (min SOC 22%) och en elmotor med nominell effekt på 402 kW. TCO beräknades både för en FCET baserat på de dimensionerade komponenterna och en lastbil som går på biodiesel. En FCET som köps 2020 blir konkurrenskraftig om vätgaspriset är 38,6 NOK/kgH2, medan vätgaspriset kan öka till 71,8 NOK/kgH2 om FCET köps 2030. Skillnaden är baserad på en framtida prisnedgång för FCET. För att finna den mest lämpliga lösningen på infrastruktur; analyserades fyra olika utformningar av vätgaspåfyllningsstationer (HRS). I tillägg jämfördes vätgasproduktionsenheter (HPU) baserat på antingen alkalisk eller PEM-typ av elektrolysator. Resultaten visade at en 350 bar HRS utan kylning, som endast kan fylla typ III lagringstankar, som det billigaste alternativet. Den alkaliska elektrolysatorn kunde producera vätgas för något lägre kostnad. Det billigaste alternativet för infrastruktur av de olika framtagna scenarios var att placera HPU bredvid HRS om minst 7 FCET tankar dagligen på varje station. Minst 3 HRS krävs längs rutten för att tillhandahålla en minsta servicenivå för FCET. När TCO för bränslecellslastbil och LCOH för infrastruktur jämfördes för ett 2020-scenario så fanns det ingen lönsam lösning. Kostnaden för att installera 3 HRS år 2020 som betjänar en lastbilflotta mellan 14-24 lastbilar skulle kosta 16,0 - 17,6 miljoner NOK/år mer än en lastbilsflotta som går på biodiesel. I ett framtida scenario där både FCET- och infrastrukturkostnaderna minskar på grund av större produktionsvolymer så kan vätgassatsning bli lönsam om minst 5 FCET tankar dagligen på varje HRS. Det motsvarar en lastbilsflotta på omkring 24 lastbilar för hela rutten. Till slut finns en rad klara rekommendationer om hur den tekno-ekonomiska analysen kan förbättras. Det upptäcktes både områden med otillräcklig dokumentation och summerades hur den teknoekonomiska modellen kan förbättras.

Fuel consumption is a major economical component of vehicles, particularly for heavy-duty vehicles. It is dependent on many factors, such as driver and environment, and control over some factors is present, e.g. route, and we can try to optimize others, e.g. driver. The driver is responsible for around 30% of the operational cost for the fleet operator and is therefore important to have efficient drivers as they also inuence fuel consumption which is another major cost, amounting to around 40% of vehicle operation. The difference between good and bad drivers can be substantial, depending on the environment, experience and other factors. In this thesis, two methods are proposed that aim at quantifying and qualifying driver performance of heavy duty vehicles with respect to fuel consumption. The first method, Fuel under Predefined Conditions (FPC), makes use of domain knowledge in order to incorporate effect of factors which are not measured. Due to the complexity of the vehicles, many factors cannot be quantified precisely or even measured, e.g. wind speed and direction, tire pressure. For FPC to be feasible, several assumptions need to be made regarding unmeasured variables. The effect of said unmeasured variables has to be quantified, which is done by defining specific conditions that enable their estimation. Having calculated the effect of unmeasured variables, the contribution of measured variables can be estimated. All the steps are required to be able to calculate the influence of the driver. The second method, Accelerator Pedal Position - Engine Speed (APPES) seeks to qualify driver performance irrespective of the external factors by analyzing driver intention. APPES is a 2D histogram build from the two mentioned signals. Driver performance is expressed, in this case, using features calculated from APPES. The focus of first method is to quantify fuel consumption, giving us the possibility to estimate driver performance. The second method is more skewed towards qualitative analysis allowing a better understanding of driver decisions and how they affect fuel consumption. Both methods have the ability to give transferable knowledge that can be used to improve driver's performance or automatic driving systems. Throughout the thesis and attached articles we show that both methods are able to operate within the specified conditions and achieve the set goal.

In the heavy truck industry, sales and service networks play an important role. Investments in network infrastructure are costly, and to be profitable, there is a critical service volume to fulfil. This is especially challenging in new markets, where service demand is low and uncertain. A possible solution is to share sales and service networks with competitors. Simultaneous cooperation and competition, co-opetition, is a complex and contradictory phenomenon that has been previously researched, but with focus on cooperation in input activities like R&D. This thesis investigates co-opetition in output activities, in sales and services, by analysing how heavy truck companies could form competitor partnerships in sales and service networks. This is done by a literature review and a multiple case study. From the analysis, a framework for assessing and designing potential competitor partnerships is presented. The framework consists of seven factors that are significant for competitor partnership success in sales and service networks; cultural fit, noncompeting products, compatible goals, excess network capacity, dedicated salespersons, high commitment, and patient implementation. This thesis contributes to science by research on co-opetition research in output activities, and by a discussion on the meaning of competition, success and partnerships.
I tunga lastbilsbranschen spelar sälj- och servicenätverk en viktig roll. Investeringar i nätverken är dyra, och för att vara lönsamma krävs en viss servicevolym. Det är särskilt utmanande på nya marknader, där efterfrågan är låg och obestämd. En möjlig lösning är att dela sälj- och servicenätverk med konkurrenter. Simultant samarbete och konkurrens, så kallad co-opetition, är ett komplext och motsägande fenomen, som tidigare forskats på med fokus på samarbete inom utveckling. Denna uppsats undersöker co-opetition inom sälj, genom att titta på hur tunga lastbilsföretag kan ingå partnerskap inom sälj- och servicenätverk tillsammans med konkurrenter. Detta görs genom en litteraturgenomgång samt en flerfallstudie. Utifrån vår analys presenteras ett ramverk för att bedöma och utforma potentiella partnerskap med konkurrenter. Ramverket består av sju viktiga faktorer för framgångsrika partnerskap inom sälj- och servicenätverk tillsammans med konkurrenter; kulturell passform (cultural fit), icke-konkurrerande produkter, kompatibla mål, överbliven kapacitet i nätverket, dedikerade säljare, högt engagemang och tålmodig implementering. Uppsatsen bidrar till forskning inom co-opetition inom sälj och med diskussion kring begreppen konkurrens, framgång och partnerskap.

Trucks are used to transport goods and services using road transportation. Emissions from the transportation industry are rising with every passing year. The Swedish government said in a report in 2009 that they are working to reduce 70% of the greenhouse gas emissions by 2030 to build a pathway for sustainable transportation (Allerup, 2019). New technologies in the field of transportation are coming to the market every year. It is important to evaluate the impacts from these technologies to support the 2030 agenda of Swedish government. Life cycle analysis of trucks can give valuable insight into the hotspots from different life cycle stages. To provide a comprehensive overview of the emissions from different types of heavy duty trucks namely Internal combustion engine trucks (Manual and driverless) and electric trucks (manual and driverless) a life cycle assessment is carried out.  From the comprehensive evaluation of results, following questions are answered. [1] Global warming potential from different types of heavy duty trucks; [2] Impacts from the new automation technology on climate change; [3] Environmental hotspots evaluation of the different truck types; and [4] Impacts of using different fuel types on the Global warming potential. Overall, the life cycle assessment can help the decision makers for taking decisions in order to fulfill the agenda 2030 of the Swedish government but still further research is needed to be done to exactly find out the emissions level of new automation technologies.
Lastbilar används för att transportera varor och tjänster med vägtransport. Utsläppen från transportbranschen ökar för varje år som går. Den svenska regeringen sa i en rapport 2009 att de arbetar för att minska 70% av växthusgasutsläppen till 2030 för att bygga en väg för hållbara transporter. Ny teknik inom transportområdet kommer till marknaden varje år. Det är viktigt att utvärdera effekterna av denna teknik för att stödja 2030-agendan för den svenska regeringen. Livscykelanalys av lastbilar kan ge värdefull inblick i hotspots från olika livscykelsteg. För att ge en omfattande översikt över utsläppen från olika typer av tunga lastbilar, nämligen IC-motor bilar (manuella och förarlösa) och elektriska lastbilar (manuella och förarlösa) genomförs en livscykelbedömning.  Från den omfattande utvärderingen av resultaten besvaras följande frågor. [1] Global uppvärmningspotential från olika typer av tunga lastbilar; [2] Effekter från den nya automatiseringstekniker på klimatförändringar. [3] Miljö Hotspots utvärdering av olika lastbilstyper; och [4] Effekter av användning av olika bränsletyper på den globala uppvärmning potentialen. Sammantaget kan livscykelbedömningen hjälpa beslutsfattarna att fatta beslut för att uppfylla den svenska regeringens dagordning 2030, men ytterligare forskning behövs för att exakt ta reda på utsläppsnivån för ny automatiseringsteknik.  Resultaten av studien visar att elbilen har lägre GWP-utsläpp än IC-motor bilarna. Den förarlösa automatiseringstekniker har 1,37% av de totala GWP-utsläppen när det gäller IC-motor bilar. Medan för elektriska lastbilar bidrar förarlös automatiseringsteknik upp till 12% av de totala utsläppen av elbil.

L’évolution croissante du prix des carburants ainsi que les normes antipollution de plus en plus drastiques obligent les fabricants de véhicules commerciaux à développer des solutions innovantes pour réduire la consommation de carburant. Dans cet objectif, comme une grande partie de l’énergie contenue dans le carburant est directement relâchée à l’ambient sous forme de chaleur, celle-ci peut être valorisée et transformée via un cycle thermodynamique secondaire. Dans ce cadre, l’importante utilisation du cycle de Rankine à travers le monde en font un candidat naturel pour une implémentation dans un véhicule. Mais contrairement à une utilisation stationnaire, de nombreux obstacles se dressent pour une intégration totale dans un poids lourd. De nombreuses études ont été menées ces trente dernières années afin de déterminer le potentiel réel d’un tel système une fois embarqué à bord d’un véhicule. Les nombreuses sources de chaleur valorisables, les contraintes inhérentes à l’application embarquée ou encore les forts régimes transitoires induits par l’utilisation du camion doivent mener à une optimisation à la fois de l’architecture du système ainsi que de son système de contrôle. L’optimisation du système mène à un choix en terme de sources chaudes et froides, de topologie, de fluide de travail ainsi que de dimensionnement des composants afin de maximiser les performances. Le système de contrôle joue lui un rôle primordial afin de tirer un bénéfice maximum d’un tel système connaissant ses limites physiques ainsi que d’assurer une utilisation efficace. Dans cette thèse, une méthodologie de conception d’un système de valorisation des rejets thermiques est proposée. En se basant sur des simulations du véhicule complet basées sur un modèle détaillé, les thématiques de la sélection du fluide de travail, des sources chaudes et froides ainsi que l’optimisation des composants et du cycle sont approchées. Par la suite, le problème de contrôle en ligne de la surchauffe à la sortie de l’évaporateur est formalisé. En tenant compte des contraintes numériques d’implémentation, différentes stratégies de commande sont mises en place, allant du contrôleur PID à des structures plus avancées telle que la commande prédictive par modèle ou une loi de commande basée sur un observateur. La plupart de ces stratégies sont validées expérimentalement sur un banc d’essai mis en place durant la thèse
The constant evolution of oil prices and the more and more stringent automotive emission standards force the original engine manufacturers to search for innovative solutions in order to reduce oil consumption. As an important part of the energy contained in the primary carrier (the fuel) is lost to the ambient through heat, it seems convenient to recover a part of this thermal energy and to turn it into fuel consumption reduction. Thermodynamic bottoming cycle such as the Rankine cycle could be used to meet this objective. Its popular use throughout the world for electricity generation makes it a natural candidate for on-board implementation in vehicles. However, a certain number of hurdles are still present before the system can be efficiently applied to heavy-duty trucks. In the last thirty years, numerous studies heave been carried out to evaluate the real potential of that kind of system on a vehicle but nothing has yet been commercialized. The heat sources to recover from, the constraints relative to the on-board application and the long and frequent transient behavior of the vehicle mean both the system architecture and its control strategy need to be optimized. The system optimization leads to a choice in terms of working fluid, heat sources and sinks, and components sizing in order to maximize power recovery and hence the fuel saving. The control plays a major role by using the capability of such a system to ensure an efficient and safe operation and limiting the interactions with the other vehicle sub-systems. In this thesis, a system design methodology is introduced to optimize the system architecture using complete model-based vehicle simulation. The constraints relative to the mobile application are taken into consideration to evaluate the potential of such a system. Modelbased control strategies for on controlled variable, namely the superheat level, are developed. Constrained by the implementation platform, different control frameworks ranging from PID to model predictive controllers or observer based controllers are developed to fit into a normal automotive electronic control unit. Most of these novel strategies were experimentally validated on a test rig developed during the thesis

Driving a heavy-duty distribution truck in an urban environment is an intricate task that requires atremendous effort from the driver. Even a minor error such as briefly looking away from the road for asecond could have fatal consequences. The automotive industry is heavily investing into making roads saferand innovations such as the seat belt has been able to save millions of lives. With the introduction of new lawsand regulation there is an emerging adaptation of driver monitoring systems in vehicles which aims to savemore lives and improve the driving experience. This master thesis presents the exploration and design of a holistic concept for how driver state monitoringcould be implemented in a manual heavy-duty distribution truck in the year of 2035 at Scania. The mainpurpose is to add value to drivers by finding solutions that bridge driver needs and monitoring technology.Driver state monitoring is a field that introduces abilities for the vehicle to connect and understand the driverin order to provide more efficient assists for a safer and more pleasurable driving experience. An iterative usercentered design process was initialized with user interviews, observations and literature reviews that resulted inan in-depth view of the driver’s needs and a summary of the latest research and innovations. A creative phasegenerated multiple ideas that where evaluated using qualitative feedback from drivers and experts. A final setof features was selected and by using 3D modelling and video editing, an eight minute long animated film wascreated that showcases the possibilities of driver state monitoring in a heavy-duty distribution truck in 2035. The final concept is a unified vision of 22 features in a heavy-duty electric distribution truck, utilizing hybriddriver state monitoring techniques in order to provide a safer and more pleasurable driving experience. It isinspired and created around the latest research and innovations in the automotive industry and aims to inspireScania in their future work to implement and innovate new solutions based on driver state monitoring. This isa thesis work by two Master of Science student within Industrial Design Engineering from Luleå University ofTechnology at Scania in the spring of 2020.
Att köra en distributionslastbil i stadsmiljö är en komplicerad uppgift som kräver en stor insats från föraren. Till och med ett litet misstag som att titta bort från vägen under en kort period kan få katastrofala följder.Fordonsindustrin investerar mycket inom säkerhet och innovationer som säkerhetsbältet har väldigtframgångsrikt bidragit till att rädda miljontals liv på vägarna. I och med nya lagar implementeras system ifordon som bevakar föraren, med målet att rädda fler liv och skapa en bättre körupplevelse. Det här examensarbetet syftar till att designa ett helhetskoncept som visar hur bevakning av föraren kanimplementeras i en manuell distributionslastbil på Scania år 2035. Det huvudsakliga målet är att skapa värdeför förarna genom att hitta lösningar som bryggar gapet mellan förarnas behov och tekniken som möjliggörbevakning av föraren. Genom att introducera denna typ av förarbevakningsteknik ges möjligheten förfordonet att bättre förstå sig på föraren, vilket i sin tur möjliggör ökad säkerhet och bättre körupplevelser. Eniterativ och användarcentrerad designprocess användes och inleddes med intervjuer, observationer och enlitteraturstudie, vilket resulterade i en djup förståelse för förarnas behov samt en summering av den senasteforskningen och innovationerna. En kreativ fas genererade en mängd idéer som sedan utvärderas med hjälp avkvalitativ feedback från både förare och experter. Ett slutligt urval av funktioner togs fram och visualiseradesgenom att skapa en animerad film. Den färdiga åtta minuter långa filmen visar på möjligheterna med tekniksom bevakar föraren i en distributionslastbil år 2035. Det slutliga konceptet förenar 22 funktioner i en elektrisk distributionslastbil. Ett flertal tekniker utnyttjas föratt bevaka föraren och tillsammans bidrar de till en säkrare och mer njutbar körupplevelse. Konceptet ärinspirerat av- och bygger på den senaste forskningen och de senaste innovationerna inom fordonsindustrin,med målet att inspirera Scania i framtida projekt där förarbevakningssystem utvecklas och implementeras.Detta arbete är ett examensarbete gjort av två civilingenjörsstudenter inom tekniks design från Luleå tekniskauniversitet på Scania under våren 2020.

The transport industry is in the middle of a conceptual shift driven by delivering the targets set by the Paris Agreement. Proactive heavy-duty vehicle companies seek to further gather knowledge in a structured way on environmental impacts of its products and services. The method to be implemented is Life Cycle Assessment (LCA). For implementation of LCA certain organisational and operational factors pre-requirements need to be addressed. The study takes key factors of Life Cycle Management (LCM) as a framework for assessing the readiness of Scania CV AB to implement LCA. Said key factors of LCM are analysed through company-based case study observations and literature review. The results indicate the company is in the process of introducing majority of the key factors of LCM. The case study tested the possibilities of the company for LCA, and attempted second phase of LCA, Life Cycle Inventory (LCI). The greatest challenge to LCA is low availability and format of data for LCA. However, the case study deeply tested the data limits and offers good insight in actions to be taken.

The truck manufacturing field is expected to go through a disruptive change in the coming decade(s) due to a predicted implementation of autonomous (self-driving) heavy-duty vehicles. Here, companies face a challenge in that autonomous vehicles (AV) will include technologies and competences from multiple industries. This will most likely have an impact on how companies manage their intellectual property (IP) to protect their inventions if they wish to keep up with the changing market. To do this in the most optimal way, it is argued that a company’s IP-strategy needs to be incorporated into their business strategy. At the same time, studies show that companies are experiencing difficulties in extracting the full potential of their IP-management. Hence, this master thesis aims at investigating how a truck manufacturing company can adapt their IP-management policy in line with future developments within these emerging technologies and how their IP-strategy can become intertwined with their business strategy. Next to a literature review of these fields, the thesis conducts a qualitative case study of a truck manufacturer that intends to be part of this change based on 11 semi-structured interviews. From the empirical results, the company’s decision-making process regarding IP is identified, whereby this thesis suggests four points of improvement that could make their IP-management policy more effective. Further, this study presents three actions that can be taken in a company to incorporate their IP-strategy with their overall business strategy. The study ends with giving suggestions for future research and presenting six managerial implications that would come by implementing the suggestions made in this thesis.

The aim of this thesis is an analysis of bending vibrations of the heavy duty truck transmission and a design of construction modifications. The next target is to evaluate the contribution of the construction modification. In the thesis is also performed analysis of shaft support stiffness.

Automated gear-shifts are critical procedures for the driveline as they are demanded to work as fast and accurate as possible. The torque control of a driveline is especially important for the driver’s feeling of driveability. In the case of gear-shifts and torque control in general, the boost pressure is key to achieve good response and thereby a fast gear-shift. An experimental study is carried out to investigate the phenomena of boost pressure drop during gear-shift and gather data for the modelling work. Results confirm the stated fact on the influence of boost pressure drop on gear-shift completion time and also indicate a clear linear dependence between initial boost pressure and the following pressure drop. A dynamic predictive model of the engine is developed with focus on implementation in a heavy duty truck, considering limitations computational complexity and calibration need between truck configurations. The resulting approach is based on a mean value modelling scheme that uses engine control system parameters and functions when possible. To be able to be predictive, a model for demanded torque and engine speed during the gear-shift is developed as reference inputs to the simulation. The simulation is based on a filling and emptying process throughout the engine dynamics, and yields final values of several engine variables such as boost pressure. The model is validated and later evaluated in comparison to measurements gathered in test vehicle experiments and in terms of robustness to input and model deviations. Computer simulations yield estimations of the boost pressure drop within acceptable limits. Consid- ering estimations used prior to this thesis the performance is good. Input deviations and modelling inaccuracies are found to inflict significant but not devastating deviations to the model output, possibly more over time with ageing of hardware taken into account. Final implementation in a heavy duty truck ecu is carried out with results indicating that the current implementation of the module is relatively computationally heavy. At the time of ending the thesis it is not possible to analyse its performance further, and it is suggested that the module is optimized in terms of computational efficiency.

This thesis presents a predictive energy management controller for long-haul hybrid trucks. In a receding horizon control framework, the vehicle speed reference, battery energy reference, and engine on/off decision are optimized over a prediction horizon. A mixed-integer quadratic program (MIQP) is formulated by performing modelling approximations and by including the binary engine on/off decision in the optimal control problem. The branch-and-bound algorithm is applied to solve this problem. Simulation results show fuel consumption reductions between 10-15%, depending on driving cycle, compared to a conventional truck. The hybrid truck without the predictive control saves significantly less. Fuel consumption is reduced by 3-8% in this case. A sensitivity analysis studies the effects on branch-and-bound iterations and fuel consumption when varying parameters related to the binary engine on/off decision. In addition, it is shown that the control strategy can maintain a safe time gap to a leading vehicle. Also, the introduction of the battery temperature state makes it possible to approximately model the dynamic battery power limitations over the prediction horizon. The main contributions of the thesis are the MIQP control problem formulation, the strategy to solve this with the branch-and-bound method, and the sensitivity analysis.

Fault diagnosis can be used to early detect faults in a technical system, which means that workshop service can be planned before a component is fully degraded. Fault diagnosis helps with avoiding downtime, accidents and can be used to reduce emissions for certain applications. Traditionally, however, diagnosis systems have been designed using ad hoc methods and a lot of system knowledge. Model-based diagnosis is a systematic way of designing diagnosis systems that is modular and offers high performance. A model-based diagnosis system can be designed by making use of mathematical models that are otherwise used for simulation and control applications. A downside of model-based diagnosis is the modeling effort needed when no accurate models are available, which can take a large amount of time. This has motivated the use of data-driven diagnosis. Data-driven methods do not require as much system knowledge and modeling effort though they require large amounts of data and data from faults that can be hard to gather. Hybrid fault diagnosis methods combining models and training data can take advantage of both approaches decreasing the amount of time needed for modeling and does not require data from faults. In this thesis work a combined data-driven and model-based fault diagnosis system has been developed and evaluated for the exhaust treatment system in a heavy-duty diesel engine truck. The diagnosis system combines physical insights and neural networks to detect and isolate faults for the exhaust treatment system. This diagnosis system is compared with another system developed during this thesis using only model-based methods. Experiments have been done by using data from a heavy-duty truck from Scania. The results show the effectiveness of both methods in an industrial setting. It is shown how model-based approaches can be used to improve diagnostic performance. The hybrid method is showed to be an efficient way of developing a diagnosis system. Some downsides are highlighted such as the performance of the system developed using data-driven and model-based methods depending on the quality of the training data. Future work regarding the modularity and transferability of the hybrid method can be done for further evaluation.

Die Entwicklung schwerer Nutzfahrzeugmotoren unterliegt dem Zielkonflikt zwischen möglichst geringen Betriebskosten, hoher Leistung und der Einhaltung von Emissionsvorschriften. Bezüglich der Auslegung der Verdichterstufe des Abgasturboladers resultiert dies in einem Kompromiss zwischen Kennfeldbreite und den Wirkungsgraden im Nennpunkt sowie im Hauptfahrbereich. In der vorliegenden wissenschaftlichen Publikation wird untersucht, ob mit Hilfe einer geometrischen Verstellbarkeit des Verdichters eine bessere Lösung für das anspruchsvolle Anforderungsprofil gefunden werden kann. Das Ziel ist eine Reduktion des Kraftstoffverbrauchs eines 12,8l NFZ-Dieselmotors im schweren Fernverkehr, ohne dass hierbei Abstriche bezüglich weiterer Leistungsmerkmale der Verdichterstufe in Kauf genommen werden müssen. In einem ersten Schritt wird hierzu mit Hilfe der Auswertung von Lastkollektivdaten der für den Kraftstoffverbrauch relevante Betriebsbereich der Basis-Verdichterstufe identifiziert. Dieser befindet sich bei vergleichsweise geringen Massenströmen und hohen Totaldruckverhältnissen in der Nähe der Volllast-Schlucklinie im Verdichterkennfeld. Die Auswertung von ein- und dreidimensionalen Strömungssimulationen führt zur Erkenntnis, dass die hohen Tangentialgeschwindigkeiten im unbeschaufelten Diffusor ausschlagge- bend sind für die Strömungsverluste innerhalb der Verdichterstufe im Hauptfahrbereich. Eine Möglichkeit die Geschwindigkeitskomponente in Umfangsrichtung zu reduzieren, ist die Verwendung eines beschaufelten Diffusors. Zur Überprüfung des Potentials werden im Rahmen einer Parameterstudie 47 unterschiedliche Nachleitgitter im Diffusor der Basis-Verdichterstufe am Heißgasprüfstand untersucht. Es stellt sich heraus, dass durch den Einsatz einer Nachleitbeschaufelung der Verdichterwirkungsgrad um bis zu 8 Prozentpunkte verbessert werden kann, die Kennfeldbreite jedoch nicht ausreicht, um die motorischen Anforderungen bezüglich der Pumpstabilität oder der Bremsleistung zu erfüllen. Resultierend aus diesen Erkenntnissen werden drei variable Verdichter entwickelt, mit dem Ziel, den Wirkungsgradvorteil beschaufelter Diffusoren mittels einer geometrischen Verstellbarkeit für den schweren Nutzfahrzeugmotor nutzbar zu machen. Die Bewertung hinsichtlich der Ziele und Anforderungen erfolgt anhand von Versuchen am Heißgas- sowie Vollmotorenprüfstand. Die Variabilität mit der geringsten Komplexität ist die Kombination aus starrem Nachleitgitter und Schubumluftventil. Das System zeichnet sich dadurch aus, dass Strömungsabrisse im Bereich des Nachleitgitters durch Aktivieren des Schubumluftventils und somit Öffnen eines Rezirkulationskanals im Verdichtergehäuse in pumpkritischen Situationen vermieden werden können. Der Verzicht auf bewegliche Teile im Diffusor resultiert in der höchsten Reduktion des Kraftstoffverbrauchs um 0,6 − 1,4% im Hauptfahrbereich. Der Doppeldiffusor besitzt zwei separate Strömungskanäle unterschiedlicher Geometrie, die im Betrieb durch eine axiale Verschiebung mit Druckluft aktiviert werden können. Dieses völlig neuartige Konzept ermöglicht es, die Auslegungsziele auf zwei Diffusoren aufzuteilen und somit für jede Kennfeldhälfte die jeweils optimale Schaufelgeometrie auszuwählen. Mit dieser Variabilität kann die Einspritzmenge im Hauptfahrbereich um 0,5 − 0,8 Prozent gesenkt werden. Das System mit der höchsten Komplexität ist der Verdichter mit rotierbarer Nachleitbeschaufelung. Über einen elektronischen Steller können die Anstellwinkel und Halsquerschnitte in jedem Betriebspunkt den Anströmbedingungen angepasst werden, um den jeweils bestmöglichen Wirkungsgrad zu erhalten. Aufgrund der anspruchsvollen geometrischen Zwangsbedingungen bei der Auswahl der Schaufelgeometrie besitzt der Dreh- schaufler mit 0,3−0,6% das geringste Potential zur Verbesserung der Kraftstoffsparsamkeit, erzielt jedoch das beste Ergebnis bezüglich der Bremsleistung und der Pumpstabilität
Reducing the total costs of ownership, achieving the rated engine power and compliance with exhaust-emission legislation are competing goals regarding the development of heavy duty engines. This leads to demanding requirements for the aerodynamic design of the turbocharger compressor stage such as high efficiencies at various operating points and a broad map width. The aim of the present doctoral thesis is to investigate the potential of a compressor with variable geometry in order to obtain a better compromise between efficiency and compressor map width for the purpose of increasing fuel economy without sacrifices concerning the rated power, engine brake performance or surge stability. In a first step, the evaluation of load cycles yields operating points on which the fuel consumption is heavily dependent. Results of 1D- and 3D fluid flow simulations show that the high tangential velocity in the vaneless diffusor is the main cause for the reduction of compressor efficiency in the main driving range. A parameter study containing 47 different geometries is conducted at a hot gas test rig in order to examine the potential of vaned diffusers regarding the reduction of the tangential velocity component. It can be seen that by introducing diffuser vanes compressor efficiency can be increased by up to 8 percent. The narrow map width however prevents the use of a fixed geometry for heavy duty engines. Based on those results three variable geometry compressors are developed with the goal of maintaining the efficiency benefit of vaned diffusers while increasing the map width by adjustable geometric features. The evaluation of the variable compressor systems is based on hot gas and engine test bench measurements. The variable compressor system with the lowest complexity utilizes a recirculation valve in the compressor housing in combination with a fixed geometry vaned diffuser in order to improve the surge margin for a short period of time at a sudden load drop. The abandonment of functional gaps in the diffuser leads to the highest improvement of fuel economy of 0,6 − 1,4% in the main driving range. The compressor with stacked diffuser vanes has two separate flow channels in the diffuser. During engine operation only one vaned diffuser geometry is active. The axial movement is performed via pressure chambers in the compressor and bearing housing. The two diffuser geometries are either optimized for high or low mass flows. This way the fuel consumption in the main driving range can be reduced by 0,5 − 0,8%. The compressor with pivoting vanes in the diffuser has the highest complexity of all systems. With the aid of an electronic actuator the vane inlet angle and throat area can be adjusted to the impeller outlet flow conditions at each operating point. As a consequence the pivoting vanes compressor achieves the best results regarding engine brake performance and surge stability. The fuel economy in the main driving range can be improved by 0,3 − 0,6%. Higher benefits are prevented by demanding geometric constraints in order to ensure the rotatability of the vanes and to prevent vibrations of the impeller blades

The weight of a heavy duty vehicle plays an important role when dealing with different control systems. Examples of control units in a truck that need this parameter are the ones used to control the brakes, the engine and the gearbox. An accurate estimation of the weight leads not only to a more fuel efficient and safer transport, but also assures the driver that current law limits are not exceeded. The weight can be estimated with pretty good accuracy if the truck is equipped with air suspension. In trucks that lack this type of suspension other methods are used to estimate the weight. At present these methods are inaccurate. In this thesis a new method where the weight is to be estimated through frequency analysis of the truck's driveline is developed and evaluated.

A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science in Engineering. Johannesburg, November 1994.
Inventories are produced, used (e.g. for raw materials, supplies, spare parts, and So forth) or distributed by every organisation. Moreover, inventories represent a major investment from the perspectives of both individual firms and entire national economies. In addition, enormous costs are incurred in the planning, scheduling, control and actual carrying out of replenlshment-Iprocuretnentl related activities. Interest in the subject of inventory management is constantly increasing, yet Silver and Petarsonlll (P(eface) found that "although invi ,~ory management ha.l been studied in considerable depth from a theoretical perspective, yet, those of us who, throuah consulting work, come into. clos>!)contact with mananerlal decision procedures in this arer are repeatedly surprised to find how limited, and ad hoc, many of the existing decision systems actually are. The rate at which theory has been developed has far outstripped the rate at which decision practices of firms have been successft,Jlly upgraded. A major g~o has existed between the theoretical solutions, on the one hand, and the real world problems, on the other". Inventory control is the science-based art of ensuring that lust enough inventory (or stockl is held by an organisation to meet both its internal and external demand commitments economically. There can be disadvantages in holding either too much 01 too little inventory. Therefore, inventory control is primarily concerned with obtaining the correct inventory with compromise between these two extremes. The control and maintenance of inventories is a problem common to all enterprises in any sector of a given economy. The primary aim of this study is to identify What the inventory policy of a company shoull;I be to Secure a reduction in inventory-related costs while maintaining a high level of customer service. Lewis(2) defines two bMlt:~ tvpes of inventory policy. Those in which decisions concerning replenishment are based on the lellel of inventory held, are known as "fixed-order quantity models" or "re-order level policies" and those in which such declslons arc made on a time basis are known as "fixed-time period models" or "re-order cycle policies". According to Nadder(3) (7I 11) the basic distinction between fixed-order quantity models and fixed-tlme period models is that the former are "event-triggered" while the latter are "time-triggered". That is, a fixed-order quantity model initiates an order when the "event" of reaching a specified re-order level occurs. This event may take place at any time, depending on the demand for the items considered. In contrast, the fixed-time period model is limited to placing orders at the end of a predetermined time period; hence, the passage of time alone "triggers" the model. In this thesis, we shall discuss both classical inventory models and heuristic models. We shall also conduct an investigation into the factors affecting high levels of inventory ~ mainly lead times (supplier and internal lea' times) in relation to spare 9arts in the heavv-dutv truck and bus industry. The thesis also suggests guidelines for controlling stock or these types of commodities in a practical environment. This will be done by either researching the existing inventory models or developing new inventory models or a combination of both, the intention being not to look for absolute optimisation, but rather to achieve significant improvements over current operations.
GR 2016

A rear loading refuse truck was simulated with a conventional and hydraulic hybrid configuration. Models for the hydraulic hybrid components were developed to simulate the system. A control algorithm was developed using a stochastic dynamic programming approach. The results did not match those that are advertised by the commercially available systems, but reasons for this deviation are discussed. The predicted improvement in fuel economy ranged from 1% to 15% depending on variance in drive cycle and vehicle weight. A brief analysis of the cost of the hybrid system was also conducted based on an estimated drive cycle. This analysis showed that, at current fuel prices of about $4.00/gallon, the system may not make financial sense for a 10 year period of ownership.
text

碩士
國立成功大學
航空太空工程學系碩博士班
100
In 2009, transportation sector consumed almost 20% of the world’s total delivered energy. More than 50% of world’s liquid fuel is consumed by the transportation alone, and the consumption is predicted to keep increasing for several decades in near future. Among the transportation modes, heavy trucks have been the most dominant in commercial freight industry. Fifty percent of the energy consumption of ground vehicles is used to overcome the aerodynamic drag. These facts have triggered the idea of reducing the drag of heavy duty vehicles in order to reduce the fuel consumption. Efforts to reduce the aerodynamic drag of heavy vehicles have been seriously performed since 1950s. It is learned that the trailer back is the region with high total pressure loss contributing to the total drag. Fully three-dimensional Computational Fluid Dynamics (CFD) simulations were then proposed to evaluate this phenomenon. The research performed simulations of a Class-8 truck model, known as the Generic Conventional Model (GCM). The GCM has also been tested experimentally by the NASA using the 12-Ft Pressure Wind Tunnel in order to provide baseline measurements for further computational researches in the truck drag. The CFD simulations of the GCM were conducted at Reynolds number of 4 million, and Mach number of 0.15. The unstructured grid, false time approach, and the RNG k–epsilon turbulence model were used in the simulations. Mesh size was varied to ensure the mesh independency of the results. After successful computations, it is found that there are three critical regions which contribute to the truck drag, the tractor-trailer gap, the trailer back, and the trailer underbody. The tractor dominated the drag with 39% of the total drag, followed by the trailer with 37% of the total drag. As a final point, it is hoped that this research have brought and given birth to new ideas of truck drag reduction device potential.

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.

碩士
國立高雄應用科技大學
工業工程與管理系碩士在職專班
106
With the continuous increase of transportation volume between global industries, the method and efficiency of material handling and product shipment have become very important. Whether the upload and download speed of the incoming raw material or outgoing product shipment, the enterprise must take into much account of efficiency and accuracy, which should have good handling and transportation system, equipment, and upload/download approach. In so doing, it can facilitate the turnover of material and product, lower the cost, and then enhance the enterprise competitiveness. Since material handling and product shipment occupy the considerable cost ratio, performance evaluation is very important, with which this study uses the heavy duty truck of the KY case company to explore the influence on the enterprise. The current research applies analytic hierarchy process (AHP) to building the evaluation model, through literature review and expert interview to find the key factors of the performance evaluation of material handling and product shipment, including the four constructs of the fitness of the handling and transportation of machine and equipment, the quality of operators, the layout of on-site location, and finance planning. From the four constructs, the twelve rules are developed. As the results show in the current research, the fitness of the handling and transportation machine and equipment performance is the most important factor, followed by the quality of operators, the layout of on-site location, and finance planning. But in terms of the rules, the top five important factors are the size of the operation space, product structure and turnover, the familiarity of the process, the work safety inspection, and machine and equipment idle and operation time. This reflects that, for the handling and transportation of machine and equipment performance, except the machine and equipment construct, in which all rules are very important and must be particularly careful, other constructs have their important unique rule.

Thesis (Ph. D.) -- University of Tennessee, Knoxville, 2005.
Title from title page screen (viewed on June 28, 2005). Thesis advisor: Terry L. Miller. Document formatted into pages (xii, 467 p. ; ill. (some col.), maps). Vita. Includes bibliographical references (p. 118-122).

Die Entwicklung schwerer Nutzfahrzeugmotoren unterliegt dem Zielkonflikt zwischen möglichst geringen Betriebskosten, hoher Leistung und der Einhaltung von Emissionsvorschriften. Bezüglich der Auslegung der Verdichterstufe des Abgasturboladers resultiert dies in einem Kompromiss zwischen Kennfeldbreite und den Wirkungsgraden im Nennpunkt sowie im Hauptfahrbereich. In der vorliegenden wissenschaftlichen Publikation wird untersucht, ob mit Hilfe einer geometrischen Verstellbarkeit des Verdichters eine bessere Lösung für das anspruchsvolle Anforderungsprofil gefunden werden kann. Das Ziel ist eine Reduktion des Kraftstoffverbrauchs eines 12,8l NFZ-Dieselmotors im schweren Fernverkehr, ohne dass hierbei Abstriche bezüglich weiterer Leistungsmerkmale der Verdichterstufe in Kauf genommen werden müssen. In einem ersten Schritt wird hierzu mit Hilfe der Auswertung von Lastkollektivdaten der für den Kraftstoffverbrauch relevante Betriebsbereich der Basis-Verdichterstufe identifiziert. Dieser befindet sich bei vergleichsweise geringen Massenströmen und hohen Totaldruckverhältnissen in der Nähe der Volllast-Schlucklinie im Verdichterkennfeld. Die Auswertung von ein- und dreidimensionalen Strömungssimulationen führt zur Erkenntnis, dass die hohen Tangentialgeschwindigkeiten im unbeschaufelten Diffusor ausschlagge- bend sind für die Strömungsverluste innerhalb der Verdichterstufe im Hauptfahrbereich. Eine Möglichkeit die Geschwindigkeitskomponente in Umfangsrichtung zu reduzieren, ist die Verwendung eines beschaufelten Diffusors. Zur Überprüfung des Potentials werden im Rahmen einer Parameterstudie 47 unterschiedliche Nachleitgitter im Diffusor der Basis-Verdichterstufe am Heißgasprüfstand untersucht. Es stellt sich heraus, dass durch den Einsatz einer Nachleitbeschaufelung der Verdichterwirkungsgrad um bis zu 8 Prozentpunkte verbessert werden kann, die Kennfeldbreite jedoch nicht ausreicht, um die motorischen Anforderungen bezüglich der Pumpstabilität oder der Bremsleistung zu erfüllen. Resultierend aus diesen Erkenntnissen werden drei variable Verdichter entwickelt, mit dem Ziel, den Wirkungsgradvorteil beschaufelter Diffusoren mittels einer geometrischen Verstellbarkeit für den schweren Nutzfahrzeugmotor nutzbar zu machen. Die Bewertung hinsichtlich der Ziele und Anforderungen erfolgt anhand von Versuchen am Heißgas- sowie Vollmotorenprüfstand. Die Variabilität mit der geringsten Komplexität ist die Kombination aus starrem Nachleitgitter und Schubumluftventil. Das System zeichnet sich dadurch aus, dass Strömungsabrisse im Bereich des Nachleitgitters durch Aktivieren des Schubumluftventils und somit Öffnen eines Rezirkulationskanals im Verdichtergehäuse in pumpkritischen Situationen vermieden werden können. Der Verzicht auf bewegliche Teile im Diffusor resultiert in der höchsten Reduktion des Kraftstoffverbrauchs um 0,6 − 1,4% im Hauptfahrbereich. Der Doppeldiffusor besitzt zwei separate Strömungskanäle unterschiedlicher Geometrie, die im Betrieb durch eine axiale Verschiebung mit Druckluft aktiviert werden können. Dieses völlig neuartige Konzept ermöglicht es, die Auslegungsziele auf zwei Diffusoren aufzuteilen und somit für jede Kennfeldhälfte die jeweils optimale Schaufelgeometrie auszuwählen. Mit dieser Variabilität kann die Einspritzmenge im Hauptfahrbereich um 0,5 − 0,8 Prozent gesenkt werden. Das System mit der höchsten Komplexität ist der Verdichter mit rotierbarer Nachleitbeschaufelung. Über einen elektronischen Steller können die Anstellwinkel und Halsquerschnitte in jedem Betriebspunkt den Anströmbedingungen angepasst werden, um den jeweils bestmöglichen Wirkungsgrad zu erhalten. Aufgrund der anspruchsvollen geometrischen Zwangsbedingungen bei der Auswahl der Schaufelgeometrie besitzt der Dreh- schaufler mit 0,3−0,6% das geringste Potential zur Verbesserung der Kraftstoffsparsamkeit, erzielt jedoch das beste Ergebnis bezüglich der Bremsleistung und der Pumpstabilität.:1 Einleitung 1.1 Einführung 1.2 Stand der Technik 1.3 Zielsetzung 2 Grundlagen 2.1 Der schwere Nutzfahrzeugmotor 2.1.1 Aufbau 2.1.2 Kenngrößen 2.1.3 Motorbremse 2.2 Der Turbolader-Radialverdichter 2.2.1 Systembeschreibung 2.2.2 Definition von Kenngrößen 2.2.3 ThermodynamischeBeschreibung 2.3 Thermodynamik des Aufladesystems 2.3.1 Stationäre Lastkurven im Verdichterkennfeld 2.3.2 Grenzwerte im Stationärbetrieb 2.3.3 Transientverhalten 3 Methodik 3.1 Lösungsweg 3.2 Lastkollektivauswertung 3.3 Parametrisiertes Diffusormodell 3.3.1 Geometrischer Aufbau 3.3.2 Auslegungsgrößen 3.3.3 Parameterstudie 3.4 Simulation 3.4.1 1D-Strömungssimulation in Diffusor und Volute 3.4.2 3D-Strömungssimulation der Verdichterstufe 3.4.3 Motorprozesssimulation 3.5 Heißgasprüfstand 3.5.1 Kennfeldvermessung 3.5.2 Aerodynamikmessung 3.5.3 Verkokungsanfälligkeit 3.6 Motorprüfstand 3.6.1 Aufbau 3.6.2 Randbedingungen 3.6.3 Akustikmessung 4 Ergebnisse 4.1 Validierung 4.1.1 Strömungszustand am Verdichterradaustritt 4.1.2 Simulation der Verdichterstufe mit unbeschaufeltem Diffusor 4.1.3 Simulation der Verdichterstufe mit beschaufeltem Diffusor 4.2 Verlustanalyse Basisverdichter 4.2.1 Auswertung der Lastkollektive 4.2.2 Aerodynamische Verlustanalyse 4.2.3 Strömungsmechanik im Diffusor 4.3 Parameterstudie beschaufelter Diffusoren 4.3.1 Einfluss von Nachleitgittern auf das Verdichterkennfeld 4.3.2 Anforderungen des schweren Nutzfahrzeugmotors 4.4 Aerodynamik beschaufelter Diffusoren 4.4.1 Auslegungskriterien 4.5 Verkokung beschaufelter Diffusoren 5 Variable Verdichter 5.1 VRVC - Starres Nachleitgitter mit Schubumluftventil 5.1.1 Auslegung und Konstruktion 5.1.2 Heißgasprüfstand 5.2 VSVC-Doppeldiffusor 5.2.1 Auslegung und Konstruktion 5.2.2 Heißgasprüfstand 5.3 VPVC-RotierbareSchaufeln 5.3.1 Auslegung und Konstruktion 5.3.2 Heißgasprüfstand 5.4 Verhalten variabler Verdichter am schweren NFZ-Motor 5.4.1 Volllast 5.4.2 Lastvariation 5.4.3 DynamischesAnsprechverhalten 5.4.4 Low-End Torque 5.4.5 Dynamische Pumpstabilität 5.4.6 Bremsbetrieb 5.4.7 Ansteuerung 5.4.8 Akustik 5.5 Übersicht 6 Zusammenfassung und Ausblick 7 Anhang Literaturverzeichnis
Reducing the total costs of ownership, achieving the rated engine power and compliance with exhaust-emission legislation are competing goals regarding the development of heavy duty engines. This leads to demanding requirements for the aerodynamic design of the turbocharger compressor stage such as high efficiencies at various operating points and a broad map width. The aim of the present doctoral thesis is to investigate the potential of a compressor with variable geometry in order to obtain a better compromise between efficiency and compressor map width for the purpose of increasing fuel economy without sacrifices concerning the rated power, engine brake performance or surge stability. In a first step, the evaluation of load cycles yields operating points on which the fuel consumption is heavily dependent. Results of 1D- and 3D fluid flow simulations show that the high tangential velocity in the vaneless diffusor is the main cause for the reduction of compressor efficiency in the main driving range. A parameter study containing 47 different geometries is conducted at a hot gas test rig in order to examine the potential of vaned diffusers regarding the reduction of the tangential velocity component. It can be seen that by introducing diffuser vanes compressor efficiency can be increased by up to 8 percent. The narrow map width however prevents the use of a fixed geometry for heavy duty engines. Based on those results three variable geometry compressors are developed with the goal of maintaining the efficiency benefit of vaned diffusers while increasing the map width by adjustable geometric features. The evaluation of the variable compressor systems is based on hot gas and engine test bench measurements. The variable compressor system with the lowest complexity utilizes a recirculation valve in the compressor housing in combination with a fixed geometry vaned diffuser in order to improve the surge margin for a short period of time at a sudden load drop. The abandonment of functional gaps in the diffuser leads to the highest improvement of fuel economy of 0,6 − 1,4% in the main driving range. The compressor with stacked diffuser vanes has two separate flow channels in the diffuser. During engine operation only one vaned diffuser geometry is active. The axial movement is performed via pressure chambers in the compressor and bearing housing. The two diffuser geometries are either optimized for high or low mass flows. This way the fuel consumption in the main driving range can be reduced by 0,5 − 0,8%. The compressor with pivoting vanes in the diffuser has the highest complexity of all systems. With the aid of an electronic actuator the vane inlet angle and throat area can be adjusted to the impeller outlet flow conditions at each operating point. As a consequence the pivoting vanes compressor achieves the best results regarding engine brake performance and surge stability. The fuel economy in the main driving range can be improved by 0,3 − 0,6%. Higher benefits are prevented by demanding geometric constraints in order to ensure the rotatability of the vanes and to prevent vibrations of the impeller blades.:1 Einleitung 1.1 Einführung 1.2 Stand der Technik 1.3 Zielsetzung 2 Grundlagen 2.1 Der schwere Nutzfahrzeugmotor 2.1.1 Aufbau 2.1.2 Kenngrößen 2.1.3 Motorbremse 2.2 Der Turbolader-Radialverdichter 2.2.1 Systembeschreibung 2.2.2 Definition von Kenngrößen 2.2.3 ThermodynamischeBeschreibung 2.3 Thermodynamik des Aufladesystems 2.3.1 Stationäre Lastkurven im Verdichterkennfeld 2.3.2 Grenzwerte im Stationärbetrieb 2.3.3 Transientverhalten 3 Methodik 3.1 Lösungsweg 3.2 Lastkollektivauswertung 3.3 Parametrisiertes Diffusormodell 3.3.1 Geometrischer Aufbau 3.3.2 Auslegungsgrößen 3.3.3 Parameterstudie 3.4 Simulation 3.4.1 1D-Strömungssimulation in Diffusor und Volute 3.4.2 3D-Strömungssimulation der Verdichterstufe 3.4.3 Motorprozesssimulation 3.5 Heißgasprüfstand 3.5.1 Kennfeldvermessung 3.5.2 Aerodynamikmessung 3.5.3 Verkokungsanfälligkeit 3.6 Motorprüfstand 3.6.1 Aufbau 3.6.2 Randbedingungen 3.6.3 Akustikmessung 4 Ergebnisse 4.1 Validierung 4.1.1 Strömungszustand am Verdichterradaustritt 4.1.2 Simulation der Verdichterstufe mit unbeschaufeltem Diffusor 4.1.3 Simulation der Verdichterstufe mit beschaufeltem Diffusor 4.2 Verlustanalyse Basisverdichter 4.2.1 Auswertung der Lastkollektive 4.2.2 Aerodynamische Verlustanalyse 4.2.3 Strömungsmechanik im Diffusor 4.3 Parameterstudie beschaufelter Diffusoren 4.3.1 Einfluss von Nachleitgittern auf das Verdichterkennfeld 4.3.2 Anforderungen des schweren Nutzfahrzeugmotors 4.4 Aerodynamik beschaufelter Diffusoren 4.4.1 Auslegungskriterien 4.5 Verkokung beschaufelter Diffusoren 5 Variable Verdichter 5.1 VRVC - Starres Nachleitgitter mit Schubumluftventil 5.1.1 Auslegung und Konstruktion 5.1.2 Heißgasprüfstand 5.2 VSVC-Doppeldiffusor 5.2.1 Auslegung und Konstruktion 5.2.2 Heißgasprüfstand 5.3 VPVC-RotierbareSchaufeln 5.3.1 Auslegung und Konstruktion 5.3.2 Heißgasprüfstand 5.4 Verhalten variabler Verdichter am schweren NFZ-Motor 5.4.1 Volllast 5.4.2 Lastvariation 5.4.3 DynamischesAnsprechverhalten 5.4.4 Low-End Torque 5.4.5 Dynamische Pumpstabilität 5.4.6 Bremsbetrieb 5.4.7 Ansteuerung 5.4.8 Akustik 5.5 Übersicht 6 Zusammenfassung und Ausblick 7 Anhang Literaturverzeichnis