541 |
Driver-truck models for software-in-the-loop simulationsDaniels, Oskar January 2014 (has links)
By using vehicle-to-vehicle communication, vehicles can cooperate in many waysby sending positions and other relevant data between each other. One popularexample is platooning where many, especially heavy vehicles, drive on a trailwith short distances resulting in a reduction of air resistance. To achieve a goodefficiency of the platooning it is required that vehicle fleets are coordinated, sothat the percentage of time for driving in platoon is maximized without affectingthe total driving time and distance too much. For large fleets, this is a complexoptimization problem which would be difficult to solve by only using the realworld as the test environment. To provide a more adaptable test environment for the communication and platooningcoordination, an augmented reality with virtual vehicles (“Ghost trucks")with relevant communication abilities are developed. In order to realise the virtualtesting environment for trucks, Scania initiated a project that could be dividedinto the workload of three master theses. This thesis involved the part ofdeveloping the virtual vehicles, which include the development of a truck modeland a driver model. The developed truck model consists of a single track vehicle model and severalpowertrain models of different complexity provided by Scania. Additionally, thedriver model consists of steering wheel and speed controls in order to keep thetruck on a safe distance from the lead truck and stay on a preferred lane. The keyfeature of the driver-truck model is its modular design, which provides great flexibilityin selecting the level of detail for each component. The driver-truck modelcan be duplicated and simulated together in real time and performs platooningwith each other in a road system based on the real world. As the driver-truckmodel is module based, it can easily be extended for future purposes with morecomplex functions. The driver-truck model is implemented in Simulink and the simulation performancefor different model complexity is evaluated. It is demonstrated that theflexibility of the developed model allows a balanced decision to be made betweenrealistic truck behavior and simulation speed. Furthermore, multi-truck simulationsare performed using the model, which demonstrate the effectiveness of themodel in the evaluation of truck platooning operations.
|
542 |
Field test of vehicle detection technologies for use at signalized intersections in WinnipegFlather, Colleen 22 August 2013 (has links)
The research analyzes the operating performance of three vehicle detection technologies for use in the City of Winnipeg. The technologies were: Autoscope Encore (video sensor), Iteris Vantage Edge2 (video sensor) and Matrix Wavetronix (microwave sensor). The sensors were tested in the tow eastbound lanes and two turning lanes on the intersection of Bishop Grandin Blvd and St.Mary's Road in Winnipeg, Manitoba. The research considered 24 weather, illumination, wind and traffic conditions. Testing and analysis was completed at the stop bar, and advance zone as well as for count performance. Sensitivity is a measure of the number of calls missed by the sensor. In terms of sensitivity, Iteris performed best overall, performing with greater sensitivity than Autoscope and Matrix in 17 of 24 conditions at the stop bar and outperforming in 11 of 12 conditions for advanced zone detection in this research. For count performance the Iteris had better accuracy when compared to ground truth established by Miovision Technologies, than Autoscope and Matrix.
|
543 |
Methods for Testing and Analyzing Lithium-Ion Battery Cells intended for Heavy-Duty Hybrid Electric VehiclesSvens, Pontus January 2014 (has links)
Lithium-ion batteries designed for use in heavy-duty hybrid vehicles are continuously improved in terms of performance and longevity, but they still have limitations that need to be considered when developing new hybrid vehicles. The aim of this thesis has been to study and evaluate potential test and analysis methods suitable for being used in the design process when maximizing lifetime and utilization of batteries in heavy-duty hybrid vehicles. A concept for battery cell cycling on vehicles has been evaluated. The work included development of test equipment, verification of hardware and software as well as an extended period of validation on heavy-duty trucks. The work showed that the concept has great potential for evaluating strategies for battery usage in hybrid vehicles, but is less useful for accelerated aging of battery cells. Battery cells encapsulated in flexible packaging material have been investigated with respect to the durability of the encapsulation in a demanding heavy-duty hybrid truck environment. No effect on water intrusion was detected after vibration and temperature cycling of the battery cells. Aging of commercial battery cells of the type lithium manganese oxide - lithium cobalt oxide / lithium titanium oxide (LMO-LCO/LTO) was investigated with different electrochemical methods to gain a deeper understanding of the origin of performance deterioration, and to understand the consequences of aging from a vehicle manufacturer's perspective. The investigation revealed that both capacity loss and impedance rise were largely linked to the positive electrode for this type of battery chemistry. Postmortem analysis of material from cycle-aged and calendar-aged battery cells of the type LMO-LCO/LTO and LiFePO4/graphite was performed to reveal details about aging mechanisms for those cell chemistries. Analysis of cycle-aged LMO-LCO/LTO cells revealed traces of manganese in the negative electrode and that the positive electrode exhibited the most severe aging. Analysis of cycle-aged LFP/graphite cells revealed traces of iron in the negative electrode and that the negative electrode exhibited the most severe aging. / Litiumjonbatterier anpassade för användning i tunga hybridfordon förbättras kontinuerligt med avseende på prestanda och livslängd men har fortfarande begränsningar som måste beaktas vid utveckling av nya hybridfordon. Syftet med denna avhandling har varit att studera och utvärdera potentiella prov- och analysmetoder lämpliga för användning i arbetet med att maximera livslängd och utnyttjandegrad av batterier i tunga hybridfordon. Ett koncept för battericykling på fordon har utvärderats. Arbetet innefattade utveckling av testutrustning, verifiering av hårdvara och mjukvara samt en längre periods validering på lastbilar. Arbetet har visat att konceptet har stor potential för utvärdering av strategier för användandet av batterier i hybridfordon, men är mindre användbar för åldring av batterier. Batterier kapslade i flexibelt förpackningsmaterial har undersökts med avseende på kapslingens hållbarhet i en krävande hybridlastbilsmiljö. Ingen påverkan på fuktinträngning kunde påvisas efter vibration och temperaturcykling av de testade battericellerna. Åldring av kommersiella battericeller av typen litiummanganoxid - litiumkoboltoxid/litiumtitanoxid (LMO-LCO/LTO) undersöktes med olika elektrokemiska metoder för att få en djupare förståelse för prestandaförändringens ursprung och för att förstå konsekvenserna av åldrandet ur en fordonstillverkares användarperspektiv. Undersökningen visade att både kapacitetsförlust och impedanshöjning till största delen var kopplat till den positiva elektroden för denna batterityp. Post-mortem analys av material från cyklade och kalenderåldrade kommersiella battericeller av typen LMO-LCO/LTO och LiFePO4/grafit utfördes för att avslöja detaljer kring åldringsmekanismerna för dessa cellkemier. Vid analys av cyklade LMO-LCO/LTO celler påvisades mangan i den negativa elektroden samt uppvisade den positiva elektroden kraftigast åldring. Vid analys av cyklade LFP/grafit celler påvisades järn i den negativa elektroden samt uppvisade den negativa elektroden kraftigast åldring. / <p>QC 20140520</p>
|
544 |
Fuel-Efficient Heavy-Duty Vehicle PlatooningAlam, Assad January 2014 (has links)
The freight transport industry faces big challenges as the demand for transport and fuel prices are steadily increasing, whereas the environmental impact needs to be significantly reduced. Heavy-duty vehicle (HDV) platooning is a promising technology for a sustainable transportation system. By semi-autonomously governing each platooning vehicle at small inter-vehicle spacing, we can effectively reduce fuel consumption, emissions, and congestion, and relieve driver tension. Yet, it is not evident how to synthesise such a platoon control system and how constraints imposed by the road topography affect the safety or fuel-saving potential in practice. This thesis presents contributions to a framework for the design, implementation, and evaluation of HDV platooning. The focus lies mainly on establishing fuel-efficient platooning control and evaluating the fuel-saving potential in practice. A vehicle platoon model is developed together with a system architecture that divides the control problem into manageable subsystems. Presented results show that a significant fuel reduction potential exists for HDV platooning and it is favorable to operate the vehicles at a small inter-vehicle spacing. We address the problem of finding the minimum distance between HDVs in a platoon without compromising safety, by setting up the problem in a game theoretical framework. Thereby, we determine criteria for which collisions can be avoided in a worst-case scenario and establish the minimum safe distance to a vehicle ahead. A systematic design methodology for decentralized inter-vehicle distance control based on linear quadratic regulators is presented. It takes dynamic coupling and engine response delays into consideration, and the structure of the controller feedback matrix can be tailored to the locally available state information. The results show that a decentralized controller gives good tracking performance and attenuates disturbances downstream in the platoon for dynamic scenarios that commonly occur on highways. We also consider the problem of finding a fuel-efficient controller for HDV platooning based on road grade preview information under road and vehicle parameter uncertainties. We present two model predictive control policies and derive their fuel-saving potential. The thesis finally evaluates the fuel savings in practice. Experimental results show that a fuel reduction of 3.9–6.5 % can be obtained on average for a heterogenous platoon of HDVs on a Swedish highway. It is demonstrated how the savings depend on the vehicle position in the platoon, the behavior of the preceding vehicles, and the road topography. With the results obtained in this thesis, it is argued that a significant fuel reduction potential exists for HDV platooning. / <p>QC 20140527</p>
|
545 |
The marketing of vehicles during the economic downturn / Magdalena MaliszewskaMaliszewska, Magdalena Beata January 2010 (has links)
South Africa's automotive industry has become an increasingly important contributor to the country's gross domestic product, largely through the strong growth in the motor vehicle and component exporting sector. The South African Motor Industry is ranked 20th in the world in terms of vehicle production. It is responsible for an estimated 80% of Africa's vehicle productivity and makes 0.85% of the world's vehicles.
In this study, the automotive industry in South Africa is investigated, how it was influenced during the recession which started at the end of 2008 and went through the 2009 period, what effect it had on the market as well as the influence on sales during that period.
In the literature section, the 4P's of the marketing mix are explained and discussed as well as how it influences the automotive industry. The purpose of this study is to see specifically how the Klerksdorp dealerships were influenced by the recession and what decisions they had undertaken to tackle the problems that they encountered. This study also investigates what influences the marketing mix had on the different dealerships in Klerksdorp area. From the empirical study done, the conclusion is that the dealerships in Klerksdorp were struggling through the economic crisis.
As far as the product was concerned, the different dealerships concentrated on the best selling lines during the recession period. Very few dealerships adjusted their prices and very few offered extras that were already included in the price. With the promotion, it was actually established that the dealerships did not actually put any extra effort in order to promote their vehicles. Four out of nine dealerships decreased their promotion expenditure, while the other five kept it at the same level. None of the dealerships has increased their promotional spending during the time of recession.
Finally, the recommendations to the dealerships, as how to improve the marketing and sales through the correct use of the marketing mix, especially through the use of promotion in the Klerksdorp dealerships were made. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2010.
|
546 |
Design and implementation process for controls integration using CAN bus on a full function electric vehicle conversionProvencher, Hugo 01 March 2014 (has links)
From the electrical engineering perspective, this thesis addresses the design and
implementation of the conversion process from a hybrid electric to a full function electric
vehicle (FFEV). The architecture selection process and main components of an electric
vehicle (EV) are described, and an exhaustive literature review on the controller area
network (CAN) is presented. The electrical and control system integration strategy is
explained, along with the model-based algorithm programmed into the vehicle
integration module (VIM). Emulating electronic control units (ECUs) from the original
powertrain and controlling additional ones for the electrical drivetrain through CAN bus,
along with keeping the same functionalities of a typical production vehicle makes this
vehicle conversion similar to a factory built model. Finally, the tests and results
originating from this conversion to a full electric powertrain are discussed. The vehicle
features a 83.5 kWh Li-ion battery built in-house, resulting in an estimated range of
482 km.
|
547 |
The marketing of vehicles during the economic downturn / Magdalena MaliszewskaMaliszewska, Magdalena Beata January 2010 (has links)
South Africa's automotive industry has become an increasingly important contributor to the country's gross domestic product, largely through the strong growth in the motor vehicle and component exporting sector. The South African Motor Industry is ranked 20th in the world in terms of vehicle production. It is responsible for an estimated 80% of Africa's vehicle productivity and makes 0.85% of the world's vehicles.
In this study, the automotive industry in South Africa is investigated, how it was influenced during the recession which started at the end of 2008 and went through the 2009 period, what effect it had on the market as well as the influence on sales during that period.
In the literature section, the 4P's of the marketing mix are explained and discussed as well as how it influences the automotive industry. The purpose of this study is to see specifically how the Klerksdorp dealerships were influenced by the recession and what decisions they had undertaken to tackle the problems that they encountered. This study also investigates what influences the marketing mix had on the different dealerships in Klerksdorp area. From the empirical study done, the conclusion is that the dealerships in Klerksdorp were struggling through the economic crisis.
As far as the product was concerned, the different dealerships concentrated on the best selling lines during the recession period. Very few dealerships adjusted their prices and very few offered extras that were already included in the price. With the promotion, it was actually established that the dealerships did not actually put any extra effort in order to promote their vehicles. Four out of nine dealerships decreased their promotion expenditure, while the other five kept it at the same level. None of the dealerships has increased their promotional spending during the time of recession.
Finally, the recommendations to the dealerships, as how to improve the marketing and sales through the correct use of the marketing mix, especially through the use of promotion in the Klerksdorp dealerships were made. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2010.
|
548 |
Steering capability assessment in upper limb rheumatoid arthritisPaton, Andrew Simon January 2000 (has links)
No description available.
|
549 |
Enhanced concurrent mapping and localisation using forward-looking sonarTena Ruiz, Ioseba Joaquin January 2001 (has links)
No description available.
|
550 |
Quantification of Vehicle-induced Turbulence on Roadways Using Computational Fluid Dynamics SimulationKim, Yesul 12 December 2011 (has links)
Turbulence is a significant factor in near-road air quality, as it affects the initial dilution, dispersion, and the ultimate fate of pollutants. This study used computational fluid dynamics simulations to model the turbulent kinetic energy (TKE) on roadways, focusing on vehicle-induced turbulence. TKE was shown to decay with different power-law exponents depending on vehicle types; vehicle speeds and winds affect TKE; and thermal impacts are negligible. It was found that TKE is superimposed for vehicles in series; TKE does not dissipate far laterally, and the side-by-side interactions are not significant regardless of the directions. Thus, TKE for different traffic compositions may be expressed as a sum of the contribution from each type of vehicle. Insights gained in this study may enable the quantification of TKE for various traffic scenarios based on TKE values of single vehicle of different types, and simplify the TKE estimations in regional air quality models.
|
Page generated in 0.0509 seconds