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Viewing 1 to 30 of 1491
2015-09-29
Technical Paper
2015-01-2895
Prasad Vegendla, Tanju Sofu, Rohit Saha, Mahesh Madurai Kumar, Long-Kung Hwang
This paper investigates the aerodynamic influence of multiple on-highway trucks in different platooning configurations. Complex pressure fields are generated on the highways due to interference of multiple vehicles. This pressure field causes an aerodynamic drag to be different than the aerodynamic drag of vehicle in no traffic condition. In order to study, the effect of platooning, three-dimensional modeling and numerical simulations are performed using STAR-CCM+® commercial Computational Fluid Dynamics (CFD) tool. The aerodynamic characteristics of vehicles are analyzed in five different platooning configurations with two and three vehicles in single and multiple lanes. A significant Yaw Averaged Aerodynamic Drag (YAD) reduction is observed in both leading and trailing vehicles. It is noted that YAD is based on the average result of three different yaw angles at 0, -6 and 6o. In single lane traffic, YAD reduction is up to 8% and 38% in leading and trailing vehicles, respectively.
2015-09-29
Technical Paper
2015-01-2896
Matthew Ellis, Joaquin Ivan Gargoloff, Raja Sengupta
The increasing importance of reducing greenhouse gas emissions and the ongoing evolution of vehicle-to-vehicle connectivity technologies have generated significant interest in platooning for commercial vehicles, where two or more vehicles travel in same traffic lane in relatively close proximity. This paper examines the effect of platooning on four increasingly aerodynamic tractor-trailer configurations, using a Lattice Boltzmann based CFD solver. Each platoon consisted of three identical tractor-trailer configurations traveling in the same lane at 65mph. Two different vehicle to vehicle gaps were studied, 5m and 9m, in addition to singleton vehicles, representing an effectively infinite gap. Aerodynamic drag for the lead, middle, and trailing vehicle in the platooning configurations were compared to the corresponding single vehicle tractor-trailer configuration.
2015-09-29
Technical Paper
2015-01-2897
Rick Mihelic, Jeff Smith, Matthew Ellis
Modern aerodynamic Class 8 freight tractors can improve vehicle freight efficiency and fuel economy versus older traditional style tractors when pulling Canadian style A- or B-Train double trailer long combination vehicles (LCV's) at highway speeds. This paper compares the aerodynamic performance of a current generation aerodynamic tractor with several freight hauling configurations through computational fluid dynamics evaluations using the Lattice-Boltzmann methodology. The configurations investigated include the tractor hauling a standard 53' trailer, a platooning configuration with a 30' separation distance, and an A-Train configuration including two 48' trailers connected with a dolly converter. The study demonstrates CFD's capability of evaluating extremely long vehicle combinations that might be difficult to accomplish in traditional wind tunnels due to size limitations.
2015-09-15
Technical Paper
2015-01-2480
Giorgio Gaviraghi
Developing the MAAT (Multibody advanced airship for transport ) project concept, a cruiser-feeder airship, all green, transportation system, financed by the European Union in the frame of the FP 7 research plan, we realized that is possible to explore future potential developments of the basic concepts , the multibody transportation system, also for regular aircrafts with most implications and issues that the new concept may raise.
2015-06-15
Technical Paper
2015-01-2300
Robert Fiedler, Chadwyck Musser, Petr Cuchý
Abstract This paper addresses the NVH design of a light rail vehicle whose maximum allowable interior SPL levels at certain speeds are regulated and may vary between countries, states, and cities. The objective of this study was to predict sound pressure levels (SPL) at several interior locations across a wide range of frequencies and estimate if the current design configuration will meet the noise level limits. Statistical Energy Analysis (SEA) was used to predict interior SPL and to understand and rank the various noise contribution paths and give a better understanding of the physics of transmission and what types of design changes are most effective to reduce the overall interior SPL to meet targets. A typical light rail vehicle is composed of a frame-like structure covered by lightweight panels and with interior panels that are increasingly made from composites, sandwich, laminated, or honeycomb materials or extruded panels.
2015-04-14
Technical Paper
2015-01-0282
Emrah Adamey, Guchan Ozbilgin, Umit Ozguner
Abstract Vehicle tracking problem is of crucial importance in intelligent vehicles research, as it is amongst the basic components of any comprehensive situation awareness technology. In mixed-traffic environments, where vehicles with varying degrees of sensing and communication capabilities coexist, the vehicle-tracking problem becomes particularly more demanding. In this paper, a collaborative vehicle tracking approach is presented, where onboard sensing and inter-vehicular communication resources are utilized in an efficient manner to provide track lists to all participating vehicles in a mixed-traffic environment. The approach is implemented on SimVille, our indoor testbed for urban driving, in accordance with our system development philosophy. The performance of the approach is evaluated using entropy values of vehicle tracks-an information theoretic measure of uncertainty. The experimental results of our scaled-down tests demonstrate the effectiveness of our approach.
2015-04-14
Journal Article
2015-01-0469
Ning Wang, Yafei Liu
Abstract The Chinese government initiated the “Ten Cities, Thousand Vehicles” program for electric vehicles from the year of 2009 to 2012. The demonstration results indicate that an integral city readiness system is required in the promotion of electric vehicles, including the government policies, charging infrastructure, after-sales service, business models and consumer awareness. Through the analysis of related literature and summary reports from 25 demonstration cities, a partial least squares (PLS) path model with 5 major factors and 13 observation indicators was developed to assess the city readiness of electric vehicle adoption. The 5 factors consist of government policies and investment, charging infrastructure construction and operation, business models and maintenance service system, consumer awareness education, operation scope and environmental benefits. Based on the PLS results, 25 cities are classified into 6 groups with the clustering analysis model.
2015-04-14
Technical Paper
2015-01-0294
Takamasa Koshizen, MAS Kamal, Hiroyuki Koike
Abstract Our study unveils what smart cars are needed to minimize congestion by traffic stability. We have previously considered pacer cars with single lane road networks based on a car following model, e.g. adaptive cruise control (ACC). However, pacer cars may have a limitation with multi-lane roadways in terms of lane distribution of traffic and shockwave suppression. Therefore, we motivate building a new smart car which extends the capability of pacer cars allowing lane changing at the timing of congestion detection. In essence, the congestion detection plays a role of adjusting the (time) headway of smart cars to determine whether lane changes should be undertaken. Lane changes can be used to uniformize (or equalize) lane distribution for traffic (flow) stability. Our simulation study has suggested that the proposed smart cars enforce the capability of traffic stability more than manual and pacer cars.
2015-04-14
Technical Paper
2015-01-0299
Saurav Talukdar
Abstract Control of vehicular platoons has been a problem of interest in the controls domain for the past 40 years. This problem gained a lot of popularity when the California PATH (Partners for Advanced Transportation Technology) program was operational. String stability is an important design criterion in this problem and it has been shown that lead vehicle information is essential to achieve it. This work builds upon the existing framework and presents a controller form for each follower in the string where the lead vehicle information is used explicitly to analytically demonstrate string stability. The discussion is focused on using information from immediate neighbors to achieve string stability. Recent developments in distributed control are an attractive framework for control design where each agent has access to states of the neighbors and not all agents in the network. In this work, the aim is to design sparse H2 controllers and then perform a check on string stability.
2015-04-14
Technical Paper
2015-01-0291
Radovan Miucic, Samer Rajab, Sue Bai, James Sayer, Dillon Funkhouser
Abstract Many Intelligent Transportation System (ITS) technologies have been developed to improve the safety and efficiency of cars, trucks, public transport and infrastructure. However, very few ITS have been developed specifically for the motorcycle user protection. In this paper an analysis of dynamic and static communications tests between a vehicle and two motorcycles are provided. The system enables vehicles and motorcycles to exchange safety information such as speed, heading, location, and brake status through the use of 5.9 GHz Dedicated Short Range Communication (DSRC) protocol. The vehicles and motorcycles can then assess the potential threat level based on the incoming messages from the nearby traffic. Several high-impact motorcycle-to-vehicle collision scenarios are analyzed. Technical challenges, such as motorcycle wireless unit antenna direction performance, communication performance and target classification accuracy are further investigated.
2015-04-14
Journal Article
2015-01-0297
Jianbo Lu, Dimitar Filev, Finn Tseng
Abstract This paper proposes an approach that characterizes a driver's driving behavior and style in real-time during car-following drives. It uses an online learning of the evolving Takagi-Sugeno fuzzy model combined with the Markov model. The inputs fed into the proposed algorithm are from the measured signals of on-board sensors equipped with current vehicles, including the relative distance sensors for Adaptive Cruise Control feature and the accelerometer for Electronic Stability Control feature. The approach is verified using data collected using a test vehicle from several car-following test trips. The effectiveness of the proposed approach has been shown in the paper.
2015-04-14
Technical Paper
2015-01-0296
Roman Schmied, Harald Waschl, Luigi del Re
Abstract Adaptive cruise control (ACC) systems allow a safe and reliable driving by adapting the velocity of the vehicle to velocity setpoints and the distance from preceding vehicles. This substantially reduces the effort of the driver especially in heavy traffic conditions. However, standard ACC systems do not necessarily take in account comfort and fuel efficiency. Recently some work has been done of the latter aspect. This paper extends previous works for CI engines by incorporating a prediction model of the surrounding traffic and a simplified control law capable for real time use in experiments. The prediction model itself uses sinusoidal functions as the traffic measurements often show periodic behavior and is adapted in every sample instant with respect to the predecessor's velocity. Furthermore, the controlled vehicle is forced to stay within a specific inter-vehicle distance corridor to avoid collisions and ensure safe driving.
2015-04-14
Journal Article
2015-01-0295
Dominik Moser, Harald Waschl, Roman Schmied, Hajrudin Efendic, Luigi del Re
Abstract Modern cars feature a variety of different driving assistance systems, which aim to improve driving comfort and safety as well as fuel consumption. Due to the technical advances and the possibility to consider vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, cooperative adaptive cruise control (CACC) strategies have received significant attention from both research and industrial communities. The performance of such systems can be enhanced if the future velocity of the surrounding traffic can be predicted. Generally, human driving behavior is a complex process and influenced by several environmental impacts. In this work a stochastic model of the velocity of a preceding vehicle based on the incorporation of available information sources such as V2I, V2V and radar information is presented. The main influences on the velocity prediction considered in this approach are current and previous velocity measurements and traffic light signals.
2015-03-10
Technical Paper
2015-01-0031
Jung-Ok (Jo) Kuys, Gavin Melles, Scott Thompson-Whiteside, Ajay Kapoor
Abstract The Malaysia National Automotive Policy (NAP 2014) focuses on the systemic changes needed for the country to develop a competitive and sustainable automotive manufacturing sector. Alternative electric vehicles (EV) -including the public transport sector, in particular buses - forms part of this strategy. This also features in the Transport Scenarios for the Kuala Lumpur Structure Plan for 2020. Kuala Lumpur's population is expected to reach 10 million by 2020, the current public transport system is beset by problems, e.g. route congestion, a growing trend of private car ownership among a rising middle-class, and a range of environmental and infrastructure issues which must be challenged. A human-centred design approach to public transport focuses on developing (future) scenarios to accommodate the 2020 economic, environmental and social considerations building on Design for Sustainability (DfS), user needs, behaviour change and inclusivity principles.
2015-03-10
Technical Paper
2015-01-0050
Shane Richardson, John McIver
Abstract Mining operations which utilise Haul Trucks to move product or overburden have to also build and maintain a network of roads which the Haul Truck can operate on. As the development of the mine progress typically the road network changes and the maintenance of a mining road can influence the productivity of the mine and specifically the Haul Truck fuel consumption on the mine. The current class of Ultra class Haul Trucks can have a Gross mass from 450t to 590t with 60lt to 90lt engines developing 1,830kW to 2,800kW. By managing the roughness of the mining road network the rolling resistance of the Haul Trucks can be controlled/managed within a defined band and hence the mine can control part of the Haul Truck fuel consumption. Conversely constantly maintaining mine roads affects the productivity of the mine. Typically the decision to conduct maintenance work on a Haul Road is made subjectively, based on the feel of how rough the roads are getting.
2015-01-14
Technical Paper
2015-26-0233
Marc Pinilla, Pau Kuipers
Abstract Asphalt specifications for a Wet Handling Track (WHT) are very stringent regarding coefficient of adherence and homogeneity of this coefficient over time. Currently, asphalt mixture pavements used in wet conditions have a very limited useful life and continue degrading following different patterns depending on the asphalt mixtures used. This is due to many reasons, but mainly as a consequence of supporting big strains and the extreme conditions during its useful life. During its lifetime, the asphalt is constantly immersed in water and submitted to adverse weather conditions. Moreover, Wet Handling pavements should provide very specific and stable adherence values for vehicle testing during the asphalt aging evolution. Consequently, the study, execution and testing of the new asphalt concrete mixture for the pavements and the materials used for WHT is necessary to reach durable, homogenous in time and cost effective pavements with very low adherence parameters.
2014-09-30
Technical Paper
2014-36-0359
Alessandro Cezar Pinto, Geovanni Vezzaro Mattioli
Abstract This paper describes the development of an Intelligent Traffic Lights Control System using Fuzzy Logic concepts. Fuzzy Logic offers the possibility to ‘compute with words’, by using a mechanism for representing linguistic constructs common on real world problems. This is very important when the complexity of a task (problem) exceeds a certain threshold. Real world complex problems such human controlled systems involve a certain degree of uncertainty, which cannot be handled by traditional binary set theory. The algorithm implementation will be done inside Mathworks MATLAB software, and the results will be measured on Simulink Tool to create traffic scenarios and comparisons between simple time-based algorithms and the proposed system. During Project phase, a Robustness Parameter-Diagram will be used to design the system and cover its variables, error states, possible noises and control factors.
2014-09-30
Technical Paper
2014-36-0205
Fábio Coelho Barbosa
Abstract The growing concentration of population in world metropolis caused by increasing urbanization rates has pushed the demand for high capacity and efficient public transport systems. At the same time, environmental concerns have led to increasingly stricter emission standards. In this context, transit authorities have become strongly focused on making their bus fleets more efficient and cleaner, by incorporating new alternative fuels and clean propulsion technologies. This has led to increased interest in electric driven technologies, with their intrinsic efficient, quiet and environment friendly features. Trolleybuses, a well proven mature electric technology already adopted in some cities, although efficient and clean, are burdened by high infrastructure costs and operational inflexibility.
2014-04-01
Journal Article
2014-01-0463
Clive D'Souza
The purpose of this paper is to demonstrate the impact of low- floor bus seating configuration, passenger load factor (PLF) and passenger characteristics on individual boarding and disembarking (B-D) times -a key component of vehicle dwell time and overall transit system performance. A laboratory study was conducted using a static full-scale mock-up of a low-floor bus. Users of wheeled mobility devices (n=48) and walking aids (n=22), and visually impaired (n=17) and able-bodied (n=17) users evaluated three bus layout configurations at two PLF levels yielding information on B-D performance. Statistical regression models of B-D times helped quantify relative contributions of layout, PLF, and user characteristics viz., impairment type, power grip strength, and speed of ambulation or wheelchair propulsion. Wheeled mobility device users, and individuals with lower grip strength and slower speed were impacted greater by vehicle design resulting in increased dwell time.
2014-03-24
Technical Paper
2014-01-2007
Arturo Davila, Adria Ferrer
Abstract In recent years, platooning emerged as a realistic configuration for semi-autonomous driving. In the SARTRE project, simulation and physical tests were performed to validate the platooning system not only in testing facilities but also in conventional highways. Five vehicles were adapted with autonomous driving systems to have platooning functionalities, enabling to perform platoon tests and assess the feasibility, safety and benefits. Although the tested system was in a prototype, it demonstrated sturdiness and good functionality, allowing performing conventional road tests. First of all the fuel consumption decreased up to 16% in some configurations and different gaps between the vehicles were tested in order to establish the most suitable for platooning in terms of safety and economy. Additionally, the platooning technology enables a new level of safety in highways. Around 85% of the accident causation is the human factor.
2014-01-15
Journal Article
2013-01-9094
Waleed Faris, Hesham Rakha, Salah A.M. Elmoselhy
Climate change due to greenhouse gas emissions has led to new vehicle emissions standards which in turn have led to a call for vehicle technologies to meet these standards. Modeling of vehicle fuel consumption and emissions emerged as an effective tool to help in developing and assessing such technologies, to help in predicting aggregate vehicle fuel consumption and emissions, and to complement traffic simulation models. The paper identifies the current state of the art on vehicle fuel consumption and emissions modeling and its utilization to test the environmental impact of the Intelligent Transportation Systems (ITS)’ measures and to evaluate transportation network improvements. The study presents the relevant models to ITS in the key classifications of models in this research area. It demonstrates that the trends of vehicle fuel consumption and emissions provided by current models generally do satisfactorily replicate field data trends.
2013-10-07
Technical Paper
2013-36-0108
Carlos Bustamante, Eduard Mateu, Jesús Hernández, Álvaro Arrúe
By using telecommunications, Intelligent Transport Systems (ITS) improve traffic safety and efficiency, facilitating an integral transport of people and goods. Even with the benefits obtained through ITS Systems nowadays, significant innovations will take place in the following years such as the ubiquitous and integral use of computer vision, or the development and future implementation of Cooperative ITS (C-ITS) that will allow a direct communication between vehicles (Vehicle-to-Vehicle, V2V) and with the roadside elements (Vehicle-to-Infrastructure, V2I) by means of mobile and wireless communication. In this context, the INTELVIA project was implemented, with the clear objective of developing ITS technologies and Intelligent Human-Machine Interfaces (HMI) to obtain the advantages of using information and communication technologies in the field of road transport and traffic management.
2013-09-24
Technical Paper
2013-01-2387
Giorgio Malaguti, Massimo Dian, Massimiliano Ruggeri
Ethernet is by now the most adopted bus for fast digital communications in many environments, from household entertainment, to PLC robotics in industrial assembly lines. Even in avionic applications, new standards are fixing research results. In a similar way in automotive industry, the interest in this technology is increasingly growing, pushed forward by much research and basically by the need of high throughput, that high dynamics distributed control requests. In the world of heavy-duty machines various needs suggest to investigate for a possible Ethernet Network implementation for both real time control and services. On the other hand Bosch proposes the FlexCAN, CAN Flexible rate, but it seems a short term solution for today's congested networks.
2013-09-17
Journal Article
2013-01-2303
Antonio Dumas, Mauro Madonia, Michele Trancossi, Dean Vucinic
The European project MAAT (Multi-body Advanced Airship for Transport) is producing the design of a transportation system for transport of people and goods, based on the cruiser feeder concept. This project defined novel airship concepts capable of handling safer than in the past hydrogen as a buoyant gas. In particular, it has explored novel variable shape airship concepts, which presents also intrinsic energetic advantages. It has recently conduced to the definition of an innovative design method based on the constructal principle, which applies to large transport vehicles and allows performing an effective energetic optimization and an effective optimization for the specific mission.
2013-09-08
Technical Paper
2013-24-0081
Federico Millo, Rocco Fuso, Luciano Rolando, Jianning Zhao, Andrea Benedetto, Filippo Cappadona, Paolo Seglie
Nowadays the increasing demand for sustainable mobility has fostered the introduction of innovative propulsion systems also in the public transport sector in order to achieve a significant reduction of pollutant emissions in highly congested urban areas. Within this context this paper describes the development of the HYBUS, an environmental friendly hybrid bus for on-road urban transportation, which was jointly carried out by Pininfarina and Politecnico di Torino in the framework of the AMPERE project. The first prototype of the bus was built by integrating an innovative hybrid propulsion system featuring a plug-in series architecture into the chassis of an old IVECO 490 TURBOCITY. The bus is 12 meters long and has a capacity of up to 116 passengers in the original layout. The project relied on a modular approach where the powertrain could be easily customized for size and power depending on the specific application.
2013-04-08
Technical Paper
2013-01-0621
Hidetoshi Imaizumi, Koji Sengoku
This paper clarifies influence rate of traffic-flow and eco-driving factors that have effect on on-road fuel economy and a case study was conducted to estimate the CO₂ reduction potential due to traffic-flow smoothing and eco-driving promotion by analyzing floating car data from throughout Japan. The data employed in the study was obtained from hybrid vehicles equipped with an Eco Assist system. Previous research has reported that repeated use of these vehicles enhances fuel economy by approximately 10%. First, multiple regression analysis was performed on the subject floating car data to obtain a polynomial with fuel economy as the explained variable and items related to traffic flow and eco-driving as the explanatory variables. Average travel speed was found to have the greatest effect on fuel economy.
2013-04-08
Technical Paper
2013-01-0989
Mohamad Abdul-Hak, Youssef Bazzi, Oliver Cordes, Nizar Alholou, Malok alamir
Vehicles equipped with wireless communication technology, “Dedicated Short Range Communication” are a promising field for fuel optimization navigation applications. This paper presents a vehicle routing methodology modeled as a Petri Net (PN) for optimizing travel time and vehicle emission in a connected roadway network with minimal total traffic capacity to route vehicle in a dynamically changing traffic environment, and in an optimal and predictive manner. The novel unfolded PN model presented in this paper incorporates the essential features in Dynamic Programming (DP) to solve the stochastic traffic routing problem. The effectiveness of the proposed eco-friendly navigation methodology is validated by comparing the performance with conventional travel time based navigation methods.
2013-04-08
Technical Paper
2013-01-0987
Tang Xinpeng
Two vehicles non-cooperation differential game model of the vehicle automatic tracking was established and the corresponding optimization control algorithm was proposed using the differential game's theory. Based on this method, the simulation was carried out with high speed ISO Lane Change, Sine Steer and low speed circular motion. The preliminary study result indicated that applied differential game's theory in the vehicles automatic tracking's research was completely feasible; the computation accuracy was also satisfying.
2013-04-08
Technical Paper
2013-01-0728
Hadj Hamma Tadjine, Benedikt Schonlau, Robert Schwaiger, Klaus Krumbiegel
In order to meet the growing requirements on vehicle safety, additional safety systems are usually integrated that then fulfill a certain function. The function only becomes active in the defined use cases, since it could have a negative effect on the vehicle safety in other situations, or the necessity of intervention is not at all recognized. For the implementation of a traffic system without traffic fatalities, it is very difficult to implement this method, since an infinitely large number of situations have to be taken into consideration. In an integral safety concept, the individual safety systems are closely networked and act interdependently with each other. This paper will examine in simple scenarios whether it is possible to ensure accident-free driving such that the so-called Vision Zero can be realized in any case.
2013-04-08
Journal Article
2013-01-0617
Jan-Mou Li, Zhiming Gao
It is rare for an attempt towards optimization at the fleet-level when consideration is given to the sheer number of seemingly unpredictable interactions among vehicles and infrastructure in congested urban areas. To close the gap, we introduce a simulation based framework to explore the impact of speed synchronization on fuel economy improvement for fleets in traffic. The framework consists of traffic and vehicle modules. The traffic module is used to simulate driver behavior in urban traffic; and the vehicle module is employed to estimate fuel economy. Driving schedule is the linkage between these two modules. To explore the impact, a connected vehicle technology sharing vehicle speed information is used for better fuel economy of a fleet including six vehicles. In all scenarios analyzed, the leading vehicle operates under the EPA Urban Dynamometer Driving Schedule (UDDS), while the other five vehicles follow the leader consecutively.
Viewing 1 to 30 of 1491