| 1. |
- Alam, Assad, et al.
(författare)
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Experimental evaluation of decentralized cooperative cruise control for heavy-duty vehicle platooning
- 2015
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Ingår i: Control Engineering Practice. - : Elsevier BV. - 0967-0661 .- 1873-6939. ; 38, s. 11-25
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we consider the problem of finding decentralized controllers for heavy-duty vehicle (HDV) platooning by establishing empiric results for a qualitative verification of a control design methodology. We present a linear quadratic control framework for the design of a high-level cooperative platooning controller suitable for modern HDVs. A nonlinear low-level dynamical model is utilized, where realistic response delays in certain modes of operation are considered. The controller performance is evaluated through numerical and experimental studies. It is concluded that the proposed controller behaves well in the sense that experiments show that it allows for short time headways to achieve fuel efficiency, without compromising safety. Simulation results indicate that the model mimics real life behavior. Experiment results show that the dynamic behavior of the platooning vehicles depends strongly on the gear switching logic, which is confirmed by the simulation model. Both simulation and experiment results show that the third vehicle never displays a bigger undershoot than its preceding vehicle. The spacing errors stay bounded within 6.8. m in the simulation results and 7.2. m in the experiment results for varying transient responses. Furthermore, a minimum spacing of -0.6. m and -1.9. m during braking is observed in simulations and experiments, respectively. The results indicate that HDV platooning can be conducted at close spacings with standardized sensors and control units that are already present on commercial HDVs today.
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| 2. |
- Alam, Assad, et al.
(författare)
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Heavy-Duty Vehicle Platooning for Sustainable Freight Transportation A COOPERATIVE METHOD TO ENHANCE SAFETY AND EFFICIENCY
- 2015
-
Ingår i: IEEE CONTROL SYSTEMS MAGAZINE. - 1066-033X. ; 35:6, s. 34-56
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Tidskriftsartikel (refereegranskat)abstract
- The current system of global trade is largely based on transportation and communication technology from the 20th century. Advances in technology have led to an increasingly interconnected global market and reduced the costs of moving goods, people, and technology around the world [1]. Transportation is crucial to society, and the demand for transportation is strongly linked to economic development. Specifically, road transportation is essential since about 60% of all surface freight transportation (which includes road and rail transport) is done on roads [2]. Despite the important role of road freight transportation in the economy, it is facing serious challenges, such as those posed by increasing fuel prices and the need to reduce greenhouse gas emissions. On the other hand, the integration of information and communication technologies to transportation systems-leading to intelligent transportation systems-enables the development of cooperative methods to enhance the safety and energy efficiency of transportation networks. This article focuses on one such cooperative approach, which is known as platooning. The formation of a group of heavy-duty vehicles (HDVs) at close intervehicular distances, known as a platoon (see Figure 1) increases the fuel efficiency of the group by reducing the overall air drag. The safe operation of such platoons requires the automatic control of the velocity of the platoon vehicles as well as their intervehicular distance. Existing work on platooning has focused on the design of controllers for these longitudinal dynamics, in which simple vehicle models are typically exploited and perfect environmental conditions, such as flat roads, are generally assumed. The broader perspective of how platooning can be effectively exploited in a freight transportation system has received less attention. Moreover, experimental validations of the fuel-saving potential offered by platooning have typically been performed by reproducing the perfect conditions as assumed in the design of the automatic controllers. This article focuses on these two aspects by addressing the following two objectives.
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| 3. |
- Besselink, Bart, et al.
(författare)
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Cyber-Physical Control of Road Freight Transport
- 2016
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Ingår i: Proceedings of the IEEE. - : IEEE. - 0018-9219 .- 1558-2256. ; 104:5, s. 1128-1141
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Tidskriftsartikel (refereegranskat)abstract
- Freight transportation is of outmost importance in our society and is continuously increasing. At the same time, transporting goods on roads accounts for about 26% of the total energy consumption and 18% of all greenhouse gas emissions in the European Union. Despite the influence the transportation system has on our energy consumption and the environment, road transportation is mainly done by individual long-haulage trucks with no real-time coordination or global optimization. In this paper, we review how modern information and communication technology supports a cyber-physical transportation system architecture with an integrated logistic system coordinating fleets of trucks traveling together in vehicle platoons. From the reduced air drag, platooning trucks traveling close together can save about 10% of their fuel consumption. Utilizing road grade information and vehicle-to-vehicle communication, a safe and fuel-optimized cooperative look-ahead control strategy is implemented on top of the existing cruise controller. By optimizing the interaction between vehicles and platoons of vehicles, it is shown that significant improvements can be achieved. An integrated transport planning and vehicle routing in the fleet management system allows both small and large fleet owners to benefit from the collaboration. A realistic case study with 200 heavy-duty vehicles performing transportation tasks in Sweden is described. Simulations show overall fuel savings at more than 5% thanks to coordinated platoon planning. It is also illustrated how well the proposed cooperative look-ahead controller for heavy-duty vehicle platoons manages to optimize the velocity profiles of the vehicles over a hilly segment of the considered road network.
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| 4. |
- Eilers, S., et al.
(författare)
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COMPANION-Towards Co-operative Platoon Management of Heavy-Duty Vehicles
- 2015
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Ingår i: IEEE Conference on Intelligent Transportation Systems, Proceedings, ITSC. - : IEEE. - 9781467365956 ; , s. 1267-1273
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Konferensbidrag (refereegranskat)abstract
- The objective of the EU project COMPANION is to develop co-operative mobility technologies for supervised vehicle platooning, in order to improve fuel efficiency and safety for goods transport. The potential social and environmental benefits inducted by heavy-duty vehicle platoons have been largely proven. However, until now, the creation, coordination, and operation of such platoons have been mostly neglected. In addition, the regulation and standardization of coordinated platooning, together with its acceptance by the end-users and the society need further attention and research. In this paper we give an overview over the project and present the architecture of the off-board and onboard platforms of the COMPANION cooperative platoon management system. Furthermore, the consortium reports on the first results of the human factors for platooning, legislative analysis of platooning aspects, clustering and optimization of platooning plans and prediction of congestion due to planned special events. Finally, we present the method of validation of the system via simulation and trials.
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| 5. |
- Frödin, Kerstin
(musiker, creator_code:cre_t)
-
Ska alla tecken låta? : Konsertprojekt med tre uruppföranden av svensk musik i iscensättning av Karl Dunér med ensemble Lipparella
- 2016
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Konstnärligt arbete (refereegranskat)abstract
- I projektet Ska alla tecken låta? framförde ensemblen Lipparella tre nyskrivna kompositioner av Per Mårtensson, Lisa Streich och Erik Peters. Den ”klassiska konserten” i en traditionell konsertsal förändras alltmer och ensemblen sökte med projektet nya former för närhet och dynamik i rummet mellan publiken och verken. Med projektet ville ensemblen erbjuda publiken ett spektrum av möjliga ingångar till de musikaliska och litterära verken, i lyssnandet, förståelsen och upplevelsen. Regissören Karl Dunér utvecklade det sceniska konceptet som anpassades efter olika rum och miljöer och utnyttjade olika lokalers egenart i helhetsupplevelsen.Lipparella:Mikael Bellini - kontratenorAnna lindahl - violinKerstin Frödin - blockflöjtLouise Agnani - viola da gambaPeter Söderberg - teorbSpelplatser: Baertlings foajé i första Hötorgshuset - 18 september 2016Svindersviks Paviljong i Nacka - 22 september 2016Färgfabriken - 29 september 2016Rönnells antikvariat - 13 oktober 2016Finansiärer:Statens Musikverk (projektbidrag) Diarienummer 1102/15 och Kulturrådet (samarbete med tonsättare) Projektnummer: 2014/5190
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| 6. |
- Johansson, Alexander, et al.
(författare)
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Multi-Fleet Platoon Matching : A Game-Theoretic Approach
- 2018
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Ingår i: 2018 21ST INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS (ITSC). - : IEEE. - 9781728103235 ; , s. 2980-2985
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Konferensbidrag (refereegranskat)abstract
- We consider the platoon matching problem for a set of trucks with the same origin, but different destinations. It is assumed that the vehicles benefit from traveling in a platoon for instance through reduced fuel consumption. The vehicles belong to different fleet owners and their strategic interaction is modeled as a non-cooperative game where the vehicle actions are their departure times. Each truck has a preferred departure time and its utility function is defined as the difference between its benefit from platooning and the cost of deviating from its preferred departure time. We show that the platoon matching game is an exact potential game. An algorithm based on best response dynamics is proposed for finding a Nash equilibrium of the game. At a Nash equilibrium, vehicles with the same departure time are matched to form a platoon. Finally, the total fuel reduction at the Nash equilibrium is studied and compared with that of a cooperative matching solution where a common utility function for all vehicles is optimized.
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| 7. |
- Li, Yuchao, et al.
(författare)
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A hierarchical control system for smart parking lots with automated vehicles : Improve efficiency by leveraging prediction of human drivers
- 2019
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Ingår i: Proceedings 2019 18TH EUROPEAN CONTROL CONFERENCE (ECC). - : IEEE. ; , s. 2675-2681
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Konferensbidrag (refereegranskat)abstract
- In this work, we introduce a hierarchical architecture for management of multiple automated vehicles in a parking lot provided the existence of human-driven vehicles. The proposed architecture consists of three layers: behavior prediction, vehicle coordination and maneuver control, with the first two sitting in the infrastructure and the third one equipped on individual vehicles. We assume all three layers share a consistent view of the environment by considering it as a grid world. The grid occupancy is modeled by the prediction layer via collecting information from automated vehicles and predicting human-driven vehicles. The coordination layer assigns parking spots and grants permissions for vehicles to move. The vehicle control embraces the distributed model predictive control (MPC) technique to resolve local conflicts occurred due to the simplified vehicle models used in the design of the prediction and coordination layers. Numerical evaluation shows the effectiveness of the proposed control system.
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| 8. |
- Liang, Kuo-Yun, et al.
(författare)
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Experiments on Platoon Formation of Heavy Trucks in Traffic
- 2016
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Ingår i: 2016 IEEE 19TH INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS (ITSC). - : IEEE. - 9781509018895 ; , s. 1813-1819
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Konferensbidrag (refereegranskat)abstract
- Truck platooning is a means to significantly reduce the fuel consumption for the follower vehicle as the air drag is reduced when the inter-vehicle gap between the trucks is reduced. As each truck is assigned with different start and end locations, platoons will be frequently formed and split, while driving to their respective destinations. Additionally, the trucks are not the only ones driving on the road as there are other road users, which may influence how well a platoon can be formed. In this paper, an experimental study is conducted to investigate how traffic may affect a merging maneuver of two trucks trying to form a platoon on a public highway during rush hours. We obtained traffic data from Stockholm's motorway control system to determine the traffic condition for each testrun. Furthermore, we tried different truck speeds to study if it had any impacts on merge delay. Even in light traffic condition, a platoon merge could be delayed with over 10 % compared to the ideal case with the absence of traffic. This is partially caused by persistent drivers in which we encountered them in a fourth of the runs.
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| 9. |
- Liang, Kuo-Yun
(författare)
-
Fuel-Efficient Heavy-Duty Vehicle Platoon Formation
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is a need for intelligent freight transport solutions as the demand for road freight transport is continuously increasing while carbon footprint needs to be significantly reduced. Heavy-duty vehicle (HDV) platooning is one potential solution to partially mitigate the environmental impacts as well as to reduce fuel consumption, improve traffic safety, and increase traffic throughput on congested highways. However, as each goods transport has different origin, destination, and time restriction, it is not evident how the HDVs, carrying the goods, can fully utilize the platooning benefits during individual transport missions. Thus, there is a need to systematically coordinate scattered vehicles on the road to form platoons in order to maximize the benefits of platooning. This thesis addresses the problem of merging scattered HDVs to form platoons in traffic. The first contribution of the thesis is the investigation of how and when a pair of HDVs should form platoons given their positions, speeds, and destinations. We formulate the problem as an optimization problem and we derive a break-even ratio that describes how far a vehicle should check for possible vehicles to platoon with. The second contribution is to consider traffic during the merging maneuver when forming a platoon. Traffic may disturb and delay when the two HDVs will form a platoon and such delay leads to less fuel saved than initially planned. Based on shockwave and moving bottleneck theories, we derive a merge distance predictor that calculates where the HDVs will merge depending on the traffic condition. We first validate this in a microscopic traffic simulation tool. Then, we also conduct an experimental study during one month on a public highway between Stockholm and Södertälje to evaluate the merging maneuver with different traffic densities. Lastly, we use vehicle probe data obtained from a fleet management system to investigate the potential fuel savings from coordination in a larger road network. The number of vehicles platooning can be increased significantly through coordination compared to today. The main result of this thesis indicates that merging HDVs to form platoons leads to great fuel savings and that there are significant potentials to do so in reality. Traffic needs to be considered in order to guarantee that the HDVs save fuel and deliver the goods in time. Furthermore, the earlier the transport assignment is planned ahead of time, the more opportunities there are to collaborate with other fleet owners to reduce the fuel consumption.
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| 10. |
- Liang, Kuo-Yun, et al.
(författare)
-
Heavy-Duty Vehicle Platoon Formation for Fuel Efficiency
- 2016
-
Ingår i: IEEE transactions on intelligent transportation systems (Print). - : IEEE. - 1524-9050 .- 1558-0016. ; 17:4, s. 1051-1061
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Tidskriftsartikel (refereegranskat)abstract
- Heavy-duty vehicles driving close behind each other, also known as platooning, experience a reduced aerodynamic drag, which reduces the overall fuel consumption up to 20% for the trailing vehicle. However, due to each vehicle being assigned with different transport missions (with different origins, destinations, and delivery times), platoons should be formed, split, and merged along the highways, and vehicles have to drive solo sometimes. In this paper, we study how two or more scattered vehicles can cooperate to form platoons in a fuel-efficient manner. We show that when forming platoons on the fly on the same route and not considering rerouting, the road topography has a negligible effect on the coordination decision. With this, we then formulate an optimization problem when coordinating two vehicles to form a platoon. We propose a coordination algorithm to form platoons of several vehicles that coordinates neighboring vehicles pairwise. Through a simulation study with detailed vehicle models and real road topography, it is shown that our approach yields significant fuel savings.
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| 11. |
- Liang, Kuo-Yun, et al.
(författare)
-
The Influence of Traffic on Heavy-Duty Vehicle Platoon Formation
- 2015
-
Konferensbidrag (refereegranskat)abstract
- Heavy-duty vehicle (HDV) platooning is a mean to significantly reduce the fuel consumption for the trailing vehicle. By driving close to the vehicle in front, the air drag is reduced tremendously. Due to each HDV being assigned with different transport missions, platoons will need to be frequently formed, merged, and split. Driving on the road requires interaction with surrounding traffic and road users, which will influence how well a platoon can be formed. In this paper, we study how traffic may affect a merging maneuver of two HDVs trying to form a platoon. We simulate this for different traffic densities and for different HDV speeds. Even on moderate traffic density, a platoon merge could be delayed with 20% compared to the ideal case with no traffic.
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| 12. |
- Milstead, David A., et al.
(författare)
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Search for dark matter in events with a hadronically decaying vector boson and missing transverse momentum in pp collisions at √s=13 TeV with the ATLAS detector
- 2018
-
Ingår i: Journal of High Energy Physics. - : SPRINGER. - 1029-8479 .- 1126-6708. ; 2018:10
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Tidskriftsartikel (refereegranskat)abstract
- A search for dark matter (DM) particles produced in association with a hadronically decaying vector boson is performed using pp collision data at a centre-of-mass energy of s=13 TeV corresponding to an integrated luminosity of 36.1 fb−1, recorded by the ATLAS detector at the Large Hadron Collider. This analysis improves on previous searches for processes with hadronic decays of W and Z bosons in association with large missing transverse momentum (mono-W/Z searches) due to the larger dataset and further optimization of the event selection and signal region definitions. In addition to the mono-W/Z search, the as yet unexplored hypothesis of a new vector boson Z′ produced in association with dark matter is considered (mono-Z′ search). No significant excess over the Standard Model prediction is observed. The results of the mono-W/Z search are interpreted in terms of limits on invisible Higgs boson decays into dark matter particles, constraints on the parameter space of the simplified vector-mediator model and generic upper limits on the visible cross sections for W/Z+DM production. The results of the mono-Z′ search are shown in the framework of several simplified-model scenarios involving DM production in association with the Z′ boson.[Figure not available: see fulltext.]. © 2018, The Author(s).
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| 13. |
- Valerio, Turri, 1987-, et al.
(författare)
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Fuel-optimal look-ahead adaptive cruise control for heavy-duty vehicles
- 2018
-
Ingår i: 2018 Annual American Control Conference (ACC). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538654286 ; , s. 1841-1848
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Konferensbidrag (refereegranskat)abstract
- In this paper, we investigate the problem of how to optimally control a heavy-duty vehicle following another one, commonly referred as ad-hoc or non-cooperative platooning. The problem is formulated as an optimal control problem that exploits road topography information and the knowledge of the preceding vehicle speed trajectory to compute the optimal engine torque and gear request for the vehicle under control. The optimal control problem is implemented by dynamic programming and is tested in a simulation study that compares the performance of multiple longitudinal control strategies. The proposed look-ahead adaptive cruise controller is able to achieve fuel saving up to 7% with respect to the use of a reference vehicle-following controller, by combining the benefits of adjusting the inter-vehicular distance according to the future slope with those of alternating phases of throttling and freewheeling (driving in neutral gear).
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| 14. |
- van de Hoef, Sebastian, et al.
(författare)
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A predictive framework for dynamic heavy-duty vehicle platoon coordination
- 2019
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Ingår i: ACM Transactions on Cyber-Physical Systems. - : Association for Computing Machinery. - 2378-962X .- 2378-9638. ; 4:1
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Tidskriftsartikel (refereegranskat)abstract
- This article describes a system to facilitate dynamic en route formation of heavy-duty vehicle platoons with the goal of reducing fuel consumption. Safe vehicle platooning is a maturing technology that leverages modern sensor, control, and communication technology to automatically regulate the inter-vehicle distances. Truck platooning has been shown to reduce fuel consumption through slipstreaming by up to 10% under realistic highway-driving conditions. To further benefit from this technology, a platoon coordinator is proposed, which interfaces with fleet management systems and suggests how platoons can be formed in a fuel-efficient manner over a large region. The coordinator frequently updates the plans to react to newly available information. This way, it requires a minimum of customization with respect to the logistic operations.We discuss the system architecture in detail and introduce important underlying methodological foundations. Plans are derived in computationally tractable stages optimizing fuel savings from platooning. The effectiveness of this approach is verified in a simulation study. It shows that the coordinated platooning system can improve over spontaneously occurring platooning even under the presence of disturbances. A real demonstrator has also been developed. We present data from an experiment in which three vehicles were coordinated to form a platoon on public highways under normal traffic conditions. It demonstrates the feasibility of coordinated en route platoon formation with current communication and on-board technology. Simulations and experiments support that the proposed system is technically feasible and a potential solution to the problem of using vehicle platooning in an operational context.
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| 15. |
- Ye, Chen, et al.
(författare)
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Annihilation Versus Excimer Formation by the Triplet Pair in Triplet-Triplet Annihilation Photon Upconversion
- 2019
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 141:24, s. 9578-9584
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Tidskriftsartikel (refereegranskat)abstract
- The triplet pair is the key functional unit in triplet-triplet annihilation photon upconversion. The same molecular properties that stabilize the triplet pair also allow dimers to form on the singlet energy surface, creating an unwanted energy relaxation pathway. Here we show that excimer formation most likely is a consequence of a triplet dimer formed before the annihilation event. Polarity-dependent studies were performed to elucidate how to promote wanted emission pathways over excimer formation. Furthermore, we show that the yield of triplet-triplet annihilation is increased in higher-viscosity solvents. The results will bring new insights in how to increase the upconversion efficiency and how to avoid energy-loss channels.
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