The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Larry Shughart - One of the best experts on this subject based on the ideXlab platform.
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solving real life Locomotive scheduling problems
Transportation Science, 2005Co-Authors: Ravindra K Ahuja, Jian Liu, James B Orlin, Dushyant Sharma, Larry ShughartAbstract:In the Locomotive-scheduling problem (or the Locomotive-assignment problem), we must assign a consist (a set of Locomotives) to each train in a preplanned train schedule so as to provide each train with sufficient Locomotive power to pull the train from its origin to its destination. Locomotive-scheduling problems are among the most important problems in railroad scheduling. In this paper, we report the results of a study on the Locomotive-scheduling problem as it is faced by CSX Transportation, a major U.S. railroad company. We consider the planning version of the Locomotive-scheduling model (LSM) in which multiple types of Locomotives exist, and we need to decide which set of Locomotives should be assigned to each train. We present an integrated model that determines: the set of active and deadheaded Locomotives for each train; the light-traveling Locomotives from power sources to power sinks; and train-to-train connections (for which we specify which inbound trains and outbound trains can directly connect). An important feature of our model is that we explicitly consider consist bustings and consistency. A consist is said to be busted when a set of Locomotives coming on an inbound train is broken into subsets to be reassigned to two or more outbound trains. A solution is consistent over a week if a train receives the same Locomotive assignment each day that it runs. We will provide a mixed-integer programming (MIP) formulation of the Locomotive-assignment problem. However, an MIP of this size cannot be solved to optimality or near optimality in acceptable running times using commercially available software. Using problem decomposition, integer programming, and very large-scale neighborhood search, we have developed a solution technique to solve this problem within 30 minutes of computation time on a Pentium III computer. Our solution obtained a potential savings of over 400 Locomotives over the solution obtained by the in-house software developed by CSX.
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solving real life Locomotive scheduling problems
Social Science Research Network, 2002Co-Authors: Ravindra K Ahuja, Jian Liu, James B Orlin, Dushyant Sharma, Larry ShughartAbstract:The Locomotive scheduling problem (or the Locomotive assignment problem) is to assign a consist (a set of Locomotives) to each train in a pre-planned train schedule so as to provide them sufficient power to pull them from their origins to their destinations. Locomotive scheduling problems are among the most important problems in railroad scheduling. In this paper, we report the results of a study of the Locomotive scheduling problem faced by CSX Transportation, a major US railroad company. We consider the planning version of the Locomotive scheduling model (LSM), where there are multiple types of Locomotives and we need to decide the set of Locomotives to be assigned to each train. We present an integrated model that determines the set of active and deadheaded Locomotives for each train, light traveling Locomotives from power sources to power sinks, and train-to-train connections (specifying which inbound train and outbound trains can directly connect). An important feature of our model is that we explicitly consider consist-bustings and consistency. A consist is said to be busted when the set of Locomotives coming on an inbound train is broken into subsets to be reassigned to two or more outbound trains. A solution is said to be consistent over a week with respect to a train, if the train gets the same Locomotive assignment each day it runs. We give a mixed integer programming (MIP) formulation of the problem that contains about 197 thousand integer variables and 67 thousand constraints. An MIP of this size cannot be solved to optimality or near-optimality in acceptable running times using commercially available software. Using problem decomposition, integer programming, and very large-scale neighborhood search, we developed a solution technique to solve this problem within 30 minutes of computation time on a Pentium III computer. When we compared our solution with the solution obtained by the software in-house developed by CSX, we obtained a savings of over 400 Locomotives, which translates into savings of over one hundred million dollars annually.
Maksym Spiryagin - One of the best experts on this subject based on the ideXlab platform.
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Locomotive Adhesion Control + Rail Friction Field Measurements = ?
Lecture Notes in Mechanical Engineering, 2020Co-Authors: Maksym Spiryagin, Harold Harrison, Dwayne Nielsen, Colin Cole, Chris Bosomworth, Peter Wolfs, Mark HaymanAbstract:The design and validation of a Locomotive adhesion control system is a very complex multi-disciplinary engineering problem that not only requires consideration of the electrical system but also requires to go very deeply into mechanical and material engineering as well as tribology. The typical approach for advanced Locomotive traction studies focuses on the development of the following models and algorithms: train dynamics modelling, multibody Locomotive model, traction power system model, adhesion control algorithms, wheel-rail contact modelling and track models. These are required to cover all the physical processes present in the system. One of the complicated parts of this system is how to represent the creep force characteristics at the wheel-rail interface properly without measurements being performed on existing or modified/upgraded Locomotives under traction or braking because any Locomotive field measurements involve high testing costs. This paper discusses how this can be avoided using friction measurement data obtained in the field with an experimental tribometer and how that data should be interpreted for Locomotive studies, and how it might affect Locomotive performance outcomes considering Locomotive adhesion control strategies. Numerical experiments have been performed by the co-simulation of two full traction control systems developed in Simulink, and two Locomotive mechanical models developed in Gensys multibody software, representing two standard gauge heavy haul Locomotives running under traction operational scenarios. All possible limitations and results observed during the development and implementation studies have been discussed.
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Locomotive Studies Utilizing Multibody and Train Dynamics
2017 Joint Rail Conference, 2017Co-Authors: Maksym Spiryagin, Colin Cole, Yan Quan Sun, Ingemar PerssonAbstract:Locomotive traction studies have been extensively performed in multi-body software packages. Generally, these research activities have been focused on purely mechanical system design issues and, as a result, there is a limited amount of information available on modeling Locomotives under the influence of traction/braking capabilities and train dynamics. Evidence of using results from longitudinal train dynamics simulations as input to Locomotive dynamics simulations has also been limited and information on this is rarely presented in the public domain. This means that Locomotive traction/braking studies are commonly focused on the dynamics of an individual Locomotive and are limited in terms of implementation of intrain forces. Recent progress shows some activities involving the application of approximations of lateral coupler forces to replicate a Locomotive’s dynamics on the track. However, such an approach has its own limitations and does not fully depict the real behavior of Locomotives. At this stage, the optimal technique capable of covering all Locomotive behavior issues when traveling in a train configuration is to use a co-simulation approach between a multibody software package and a train dynamics code. This paper describes a methodology for the development of such a technique and presents numerical experiments for Locomotive dynamics studies. The results obtained from co-simulation runs for three heavy haul Locomotives in a head-end consist, taking into account in-train forces and speeds, are discussed along with limitations found during the development process.
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Investigation of Locomotive multibody modelling issues and results assessment based on the Locomotive model acceptance procedure
Proceedings of the Institution of Mechanical Engineers Part F: Journal of Rail and Rapid Transit, 2013Co-Authors: Maksym Spiryagin, Colin Cole, Yan Quan Sun, Andrew George, Tim Mcsweeney, Scott SimsonAbstract:The acceptable dynamic behaviour of railway Locomotives is governed by different standards in different parts of the world. Some standards allow the use of multibody simulation tools (such as VAMPIRE, NUCARS, GENSYS and SIMPACK) in place of physical testing, but generally not for all Locomotive tests within each standard. Virtual multibody Locomotive models can allow simple analyses, such as for slightly modified and relocated Locomotives, to be completed in less time, and lower cost and effort in comparison with physical type testing. Unfortunately, the detailed Locomotive model acceptance procedures required to achieve this for Locomotive designs do not presently exist. This paper discusses the methodology behind a proposed Locomotive model acceptance procedure that is currently intended for Australian freight Locomotives, although it can be modified to suit other countries and Locomotive types. A review of relevant international standards was first undertaken to determine which tests to include and to ...
Colin Cole - One of the best experts on this subject based on the ideXlab platform.
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Locomotive Adhesion Control + Rail Friction Field Measurements = ?
Lecture Notes in Mechanical Engineering, 2020Co-Authors: Maksym Spiryagin, Harold Harrison, Dwayne Nielsen, Colin Cole, Chris Bosomworth, Peter Wolfs, Mark HaymanAbstract:The design and validation of a Locomotive adhesion control system is a very complex multi-disciplinary engineering problem that not only requires consideration of the electrical system but also requires to go very deeply into mechanical and material engineering as well as tribology. The typical approach for advanced Locomotive traction studies focuses on the development of the following models and algorithms: train dynamics modelling, multibody Locomotive model, traction power system model, adhesion control algorithms, wheel-rail contact modelling and track models. These are required to cover all the physical processes present in the system. One of the complicated parts of this system is how to represent the creep force characteristics at the wheel-rail interface properly without measurements being performed on existing or modified/upgraded Locomotives under traction or braking because any Locomotive field measurements involve high testing costs. This paper discusses how this can be avoided using friction measurement data obtained in the field with an experimental tribometer and how that data should be interpreted for Locomotive studies, and how it might affect Locomotive performance outcomes considering Locomotive adhesion control strategies. Numerical experiments have been performed by the co-simulation of two full traction control systems developed in Simulink, and two Locomotive mechanical models developed in Gensys multibody software, representing two standard gauge heavy haul Locomotives running under traction operational scenarios. All possible limitations and results observed during the development and implementation studies have been discussed.
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Locomotive Studies Utilizing Multibody and Train Dynamics
2017 Joint Rail Conference, 2017Co-Authors: Maksym Spiryagin, Colin Cole, Yan Quan Sun, Ingemar PerssonAbstract:Locomotive traction studies have been extensively performed in multi-body software packages. Generally, these research activities have been focused on purely mechanical system design issues and, as a result, there is a limited amount of information available on modeling Locomotives under the influence of traction/braking capabilities and train dynamics. Evidence of using results from longitudinal train dynamics simulations as input to Locomotive dynamics simulations has also been limited and information on this is rarely presented in the public domain. This means that Locomotive traction/braking studies are commonly focused on the dynamics of an individual Locomotive and are limited in terms of implementation of intrain forces. Recent progress shows some activities involving the application of approximations of lateral coupler forces to replicate a Locomotive’s dynamics on the track. However, such an approach has its own limitations and does not fully depict the real behavior of Locomotives. At this stage, the optimal technique capable of covering all Locomotive behavior issues when traveling in a train configuration is to use a co-simulation approach between a multibody software package and a train dynamics code. This paper describes a methodology for the development of such a technique and presents numerical experiments for Locomotive dynamics studies. The results obtained from co-simulation runs for three heavy haul Locomotives in a head-end consist, taking into account in-train forces and speeds, are discussed along with limitations found during the development process.
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Investigation of Locomotive multibody modelling issues and results assessment based on the Locomotive model acceptance procedure
Proceedings of the Institution of Mechanical Engineers Part F: Journal of Rail and Rapid Transit, 2013Co-Authors: Maksym Spiryagin, Colin Cole, Yan Quan Sun, Andrew George, Tim Mcsweeney, Scott SimsonAbstract:The acceptable dynamic behaviour of railway Locomotives is governed by different standards in different parts of the world. Some standards allow the use of multibody simulation tools (such as VAMPIRE, NUCARS, GENSYS and SIMPACK) in place of physical testing, but generally not for all Locomotive tests within each standard. Virtual multibody Locomotive models can allow simple analyses, such as for slightly modified and relocated Locomotives, to be completed in less time, and lower cost and effort in comparison with physical type testing. Unfortunately, the detailed Locomotive model acceptance procedures required to achieve this for Locomotive designs do not presently exist. This paper discusses the methodology behind a proposed Locomotive model acceptance procedure that is currently intended for Australian freight Locomotives, although it can be modified to suit other countries and Locomotive types. A review of relevant international standards was first undertaken to determine which tests to include and to ...
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simulation of curving at low speed under high traction for passive steering hauling Locomotives
Vehicle System Dynamics, 2008Co-Authors: Scott Simson, Colin ColeAbstract:The traction control in modern electric and diesel electric Locomotives has allowed rail operators to utilise high traction adhesion levels without undue risk of damage from uncontrolled wheel spin. At the same time, some Locomotive manufacturers have developed passive steering Locomotive bogies to reduce wheel rail wear and further improve Locomotive adhesion performance on curves. High Locomotive traction loads in curving are known to cause the loss of steering performance in passive steering bogies. At present there are few publications on the curving performance of Locomotive steering with linkage bogies. The most extreme traction curving cases of low speed and high adhesion for hauling Locomotives have not been fully investigated, with effects of coupler forces and cant excess being generally ignored. This paper presents a simulation study for three axle bogie Locomotives in pusher and pulling train positions on tight curves. The simulation study uses moderate and high traction adhesion levels of 16....
Michael E Iden - One of the best experts on this subject based on the ideXlab platform.
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Battery Storage of Propulsion-Energy for Locomotives
2014 Joint Rail Conference, 2014Co-Authors: Michael E IdenAbstract:Significant technical, regulatory and media attention has recently been given to the use of electrical storage batteries onboard a line-haul (long-distance) Locomotive or “energy storage tender” (coupled adjacent to a Locomotive) as a means of improving railroad fuel efficiency and reducing freight Locomotive exhaust emissions. The extent to which electrical energy stored onboard could supplement or replace diesel generated power has yet to be quantified or proven. There are significant technical design, maintainability, logistical and safety challenges to making this technology commonplace, especially for over-the-road (line-haul) freight trains. The use of electrical batteries to provide some amount of point-source fuel- and/or emissions-free Locomotive power is not a new concept. Recent claims that onboard storage of Locomotive propulsion energy is “new Locomotive technology” are unfounded. The world’s first all-battery-powered Locomotive was built in 1838 only 34 years after the world’s first steam Locomotive operated. A total of 126 identifiable Locomotives using onboard batteries to store propulsion energy have been built and operated to some extent in the United States (US) since 1920. Almost all were low-power switching Locomotives and none are currently in revenue freight service. Two high-horsepower line-haul experimental engineering test Locomotives with an experimental battery design and regenerative dynamic braking have been built (in 2004 and 2007) but very little revenue service testing has occurred. This paper reviews propulsion battery-equipped Locomotives over the past 95 years in the US, and discusses future options and possibilities including the technical and logistical challenges to such propulsion. Capturing dynamic braking energy (developed by Locomotive traction motors during deceleration or downhill operation) could be a source of onboard battery recharging, but will require significant additional Locomotive control system development work to achieve practicality. New battery technologies are being developed but none are yet practical for large-scale Locomotive applications. Retrofitting of large amounts of onboard battery storage on existing (or even future) diesel-electric Locomotives will be limited by onboard space constraints. The development and use of energy storage “tenders” will bring complications to Locomotive and train operations to make effective use (if commercialized) practical and safe. This paper is also intended to provide technical background and clarity for various regulatory agencies regarding battery energy storage technologies for future Locomotive propulsion.
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Battery Storage of Propulsion-Energy for Locomotives
2014 Joint Rail Conference, 2014Co-Authors: Michael E IdenAbstract:Significant technical, regulatory and media attention has recently been given to the use of electrical storage batteries onboard a line-haul (long-distance) Locomotive or “energy storage tender” (coupled adjacent to a Locomotive) as a means of improving railroad fuel efficiency and reducing freight Locomotive exhaust emissions. The extent to which electrical energy stored onboard could supplement or replace diesel generated power has yet to be quantified or proven. There are significant technical design, maintainability, logistical and safety challenges to making this technology commonplace, especially for over-the-road (line-haul) freight trains.The use of electrical batteries to provide some amount of point-source fuel- and/or emissions-free Locomotive power is not a new concept. Recent claims that onboard storage of Locomotive propulsion energy is “new Locomotive technology” are unfounded. The world’s first all-battery-powered Locomotive was built in 1838 only 34 years after the world’s first steam Locomotive operated. A total of 126 identifiable Locomotives using onboard batteries to store propulsion energy have been built and operated to some extent in the United States (US) since 1920. Almost all were low-power switching Locomotives and none are currently in revenue freight service. Two high-horsepower line-haul experimental engineering test Locomotives with an experimental battery design and regenerative dynamic braking have been built (in 2004 and 2007) but very little revenue service testing has occurred.This paper reviews propulsion battery-equipped Locomotives over the past 95 years in the US, and discusses future options and possibilities including the technical and logistical challenges to such propulsion.Capturing dynamic braking energy (developed by Locomotive traction motors during deceleration or downhill operation) could be a source of onboard battery recharging, but will require significant additional Locomotive control system development work to achieve practicality. New battery technologies are being developed but none are yet practical for large-scale Locomotive applications. Retrofitting of large amounts of onboard battery storage on existing (or even future) diesel-electric Locomotives will be limited by onboard space constraints. The development and use of energy storage “tenders” will bring complications to Locomotive and train operations to make effective use (if commercialized) practical and safe.This paper is also intended to provide technical background and clarity for various regulatory agencies regarding battery energy storage technologies for future Locomotive propulsion.Copyright © 2014 by ASME
Mark Hayman - One of the best experts on this subject based on the ideXlab platform.
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Locomotive Adhesion Control + Rail Friction Field Measurements = ?
Lecture Notes in Mechanical Engineering, 2020Co-Authors: Maksym Spiryagin, Harold Harrison, Dwayne Nielsen, Colin Cole, Chris Bosomworth, Peter Wolfs, Mark HaymanAbstract:The design and validation of a Locomotive adhesion control system is a very complex multi-disciplinary engineering problem that not only requires consideration of the electrical system but also requires to go very deeply into mechanical and material engineering as well as tribology. The typical approach for advanced Locomotive traction studies focuses on the development of the following models and algorithms: train dynamics modelling, multibody Locomotive model, traction power system model, adhesion control algorithms, wheel-rail contact modelling and track models. These are required to cover all the physical processes present in the system. One of the complicated parts of this system is how to represent the creep force characteristics at the wheel-rail interface properly without measurements being performed on existing or modified/upgraded Locomotives under traction or braking because any Locomotive field measurements involve high testing costs. This paper discusses how this can be avoided using friction measurement data obtained in the field with an experimental tribometer and how that data should be interpreted for Locomotive studies, and how it might affect Locomotive performance outcomes considering Locomotive adhesion control strategies. Numerical experiments have been performed by the co-simulation of two full traction control systems developed in Simulink, and two Locomotive mechanical models developed in Gensys multibody software, representing two standard gauge heavy haul Locomotives running under traction operational scenarios. All possible limitations and results observed during the development and implementation studies have been discussed.
