The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is develope...The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is developed. Using tools of Simulink, the transient characteristics during the vehicle starting, including the jerk and the clutch slip time, are provided here. Based on the analyses of the simulation results and driver’s experiences, a fuzzy controller is designed to control the clutch engagement. Simulation results verify its value.展开更多
The simulation model of the E car HS2000 including the permanent magnetic direct current motor with the augment magnet winding is constructed based on tests in order to simulate the synthetic performance of the elec...The simulation model of the E car HS2000 including the permanent magnetic direct current motor with the augment magnet winding is constructed based on tests in order to simulate the synthetic performance of the electric car. The performance of E car HS2000 is analyzed by means of modeling and programming according to data acquired during tests. The simulation results show that the performance of E car HS2000 is successfully predicted and the model and the corresponding simulation software are feasible for simulating E cars. They can be used as effective tools for analyzing the performance parameters as well as specifications of E cars during prototype stage.展开更多
Based on optimM velocity car-following model, in this paper, we propose a new railway tramc model for describing the process of train movement control. In the proposed model, we give an improved form of the optimal ve...Based on optimM velocity car-following model, in this paper, we propose a new railway tramc model for describing the process of train movement control. In the proposed model, we give an improved form of the optimal velocity function V^opt, which is considered as the desired velocity function for train movement control under different control conditions. In order to test the proposed model, we simulate and analyze the trajectories of train movements, moreover, discuss the relationship curves between the train allowable velocity and the site of objective point in detail. Analysis results indicate that the proposed model can well capture some realistic futures of train movement control.展开更多
The application of new-designed levitation controller requires extensive validation prior to enter into commercial service. However, huge mounts of approximations and assumptions lead the theoretical analysis away fro...The application of new-designed levitation controller requires extensive validation prior to enter into commercial service. However, huge mounts of approximations and assumptions lead the theoretical analysis away from the engineering practice. The experimental methods are time-consuming and financial expensive, even unrealizable due to the lack of suitable sensors. Numerical simulations can bridge the gap between the theoretical analysis and experimental techniques. A complete overall dynamic model of maglev levitation system is derived in this work, which includes the simple-supported bridges, the calculation of electromagnetic force with more details, the stress of levitation modules and the cabin. Based on the aforementioned model, it shows that the inherent nonlinearity, inner coupling, misalignments between the sensors and actuators, and self-excited vibration are the main issues that should be considered during the design process of controller. Then, the backstepping controller based on the mathematical model of the module with reasonable simplifications is proposed, and the stability proofs are listed. To show the advantage of controller, two numerical simulation experiments are carried out. Finally, the results illustrating closed-loop performance are provided.展开更多
A trajectory generator based on vehicle kinematics model was presented and an integrated navigation simulation system was designed.Considering that the tight relation between vehicle motion and topography,a new trajec...A trajectory generator based on vehicle kinematics model was presented and an integrated navigation simulation system was designed.Considering that the tight relation between vehicle motion and topography,a new trajectory generator for vehicle was proposed for more actual simulation.Firstly,a vehicle kinematics model was built based on conversion of attitude vector in different coordinate systems.Then,the principle of common trajectory generators was analyzed.Besides,combining the vehicle kinematics model with the principle of dead reckoning,a new vehicle trajectory generator was presented,which can provide process parameters of carrier anytime and achieve simulation of typical actions of running vehicle.Moreover,IMU(inertial measurement unit) elements were simulated,including accelerometer and gyroscope.After setting up the simulation conditions,the integrated navigation simulation system was verified by final performance test.The result proves the validity and flexibility of this design.展开更多
In this paper, we propose a new cellular automata model to simulate the railway traffic at station. Based on NaSch model, the proposed station model is composed of the main track and the siding track. Two different sc...In this paper, we propose a new cellular automata model to simulate the railway traffic at station. Based on NaSch model, the proposed station model is composed of the main track and the siding track. Two different schemes for trains passing through station are considered. One is the scheme of "pass by the main track, start and stop by the siding track". The other is the scheme of "two tracks play the same role". We simulate the train movement using the proposed model and analyze the traffic flow at station. The simulation results demonstrate that the proposed cellular automata model can be successfully used for the simulations of railway traffic. Some characteristic behaviors of railway traffic flow can be reproduced. Moreover, the simulation values of the minimum headway are close to the theoretical values. This result demonstrates the dependability and availability of the proposed model.展开更多
Abstract: The current method to solve the problem of active suspension control for a vehicle is often dealt with a quarter-car or half-car model. But it is not enough to use this kind of model for practical applicatio...Abstract: The current method to solve the problem of active suspension control for a vehicle is often dealt with a quarter-car or half-car model. But it is not enough to use this kind of model for practical applications. In this paper, based on considering the influence of factors such as, seat and passengers, a MDOF(multi-degree-of-freedom) model describing the vehicle motion is set up. The MODF model, which is 8DOF of four independent suspensions and four wheel tracks, is more applicable by comparison of its analysis result with some conventional vehicle models. Therefore, it is more suitable to use the 8DOF full-car model than a conventional 4DOF half-car model in the active control design for car vibration. Based on the derived 8DOF model, a controller is designed by using LQ (linear quadratic ) control theory, and the appropriate control scheme is selected by testing various performance indexes. Computer simulation is carried out for a passenger car running on a road with step disturbance and random road disturbance expressed by Power Spectral Density (PSD). Vibrations corresponding to ride comfort are derived under the foregoing road disturbances. The response results for uncontrolled and controlled system are compared. The response of vehicle vibration is greatly suppressed and quickly damped, which testifies the effect of the active suspension. The results achieved for various controllers are compared to investigate the influence of different control schemes on the control effect.展开更多
Based on the discrete time method, an effective movement control model is designed for a group of high- speed trains on a rail network. The purpose of the model is to investigate the specific traffic characteristics o...Based on the discrete time method, an effective movement control model is designed for a group of high- speed trains on a rail network. The purpose of the model is to investigate the specific traffic characteristics of high-speed trains under the interruption of stochastic irregular events. In the model, the high-speed rail traffic system is supposed to be equipped with the moving-block signalling system to guarantee maximum traversing capacity of the railway. To keep the safety of trains' movements, some operational strategies are proposed to control the movements of trains in the model, including traction operation, braking operation, and entering-station operation. The numerical simulations show that the designed model can well describe the movements of high-speed trains on the rail network. The research results can provide the useful information not only for investigating the propagation features of relevant delays under the irregular disturbance but also for rerouting and reseheduling trains on the rail network.展开更多
Based on an improved three-dimensional wheel-rail contact trace algorithm and a new model of wheel-rail contact force, wheel-rail derailment dynamical model is established on China Railways High-speed(CRH) vehicle a...Based on an improved three-dimensional wheel-rail contact trace algorithm and a new model of wheel-rail contact force, wheel-rail derailment dynamical model is established on China Railways High-speed(CRH) vehicle and developed in MATLAB software, which is called dynamical derailment system for CRH (DDSCRH). Analyzed on dynamical derailment process of high speed vehicle by DDSCRH, the critical position on chmb wheel and influence factors on lateral force for derailment are obtained. Finally, high-speed vehicle dynamical simulation is verified on DDSCRH by comparing with the existing results of the line test.展开更多
In order to improve the yaw stability of the vehicle with active front steering system, an adaptive PID-type fuzzy control scheme is designed to make the yaw rate tracking the desired values as close as possible. A 2-...In order to improve the yaw stability of the vehicle with active front steering system, an adaptive PID-type fuzzy control scheme is designed to make the yaw rate tracking the desired values as close as possible. A 2-DOF vehicle model with active front steering is built firstly, and then the fuzzy PID controller is designed in detail. The simulation investigations of the yaw stability with different steering ma- neuvers are performed. The simulation results show the effectiveness of the fuzzy PID controller for improving the vehicle's yaw stability.展开更多
Automotive manufacturing is complex and includes the coordination of design in the manufacturing system. The manufacturing approaches over the past few years, disassembly have been a key issue, and it seems that simul...Automotive manufacturing is complex and includes the coordination of design in the manufacturing system. The manufacturing approaches over the past few years, disassembly have been a key issue, and it seems that simulation models are usually tailored to address a narrow set of industrial issues. This paper describes the development of the production line in the automobile manufacturing system through design, operation, and maintenance, based on multi-objectives of Algorithm and Simulation Model called MOA-SM. The both models are being developed at three different levels: the production line in the body and assembly shop, supply chain, and the production plan. The optimization tries to involve more objectives to solve the issues in manufacturing system. A solution that may optimize one performance measure may deteriorate since other performance solutions are difficult. The resulting algorithms are comparable to the simulation and multi-object in terms of success rate, assembly times, peak forces, moments, and have assembly times superior to those of a benchmark blind search algorithm.展开更多
This paper aims to present a simulation model for heterogeneous high-speed train traffic flow based on an improved discrete-time model(IDTM).In the proposed simulation model,four train control strategies,including d...This paper aims to present a simulation model for heterogeneous high-speed train traffic flow based on an improved discrete-time model(IDTM).In the proposed simulation model,four train control strategies,including departing strategy,traveling strategy,braking strategy,overtaking strategy,are well defined to optimize train movements.Based on the proposed simulation model,some characteristics of train traffic flow are investigated.Numerical results indicate that the departure time intervals,the station dwell time,the section length,and the ratio of fast trains have different influence on traffic capacity and train average velocity.The results can provide some theoretical support for the strategy making of railway departments.展开更多
Gipps' model, a well-known safe distance car-following model, has a very strict restriction on the car-following behavior that the following vehicle has to maintain the exact safe distance to the leading vehicle t...Gipps' model, a well-known safe distance car-following model, has a very strict restriction on the car-following behavior that the following vehicle has to maintain the exact safe distance to the leading vehicle to avoid rear crash. However, this restriction is not consistent with the real traffic condition. Due to that, an enhanced safe distance car-following model is proposed first, and then calibrated and evaluated using the field data. Furthermore, the simulation is conducted to analyze the characteristics of the new model. The results of evaluation and simulation illustrate that the proposed model has higher simulation accuracy than the original Gipps' model, and can reproduce the stable flow and shock wave phenomena that are very common in real traffic.Moreover, the simulation results also prove that the enhanced model can better stabilize the traffic flow than Gipps' model.展开更多
Based on the Nagel-Schreckenberg model, we propose a new cellular automata model to simulate the urban rail traffic flow under moving block system and present a new minimum instantaneous distance formula under pure mo...Based on the Nagel-Schreckenberg model, we propose a new cellular automata model to simulate the urban rail traffic flow under moving block system and present a new minimum instantaneous distance formula under pure moving block. We also analyze the characteristics of the urban rail traffic flow under the influence of train density, station dwell times, the length of train, and the train velocity. Train delays can be decreased effectively through flexible departure intervals according to the preceding train type before its departure. The results demonstrate that a suitable adjustment of the current train velocity based on the following train velocity can greatly shorten the minimum departure intervals and then increase the capacity of rail transit.展开更多
文摘The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is developed. Using tools of Simulink, the transient characteristics during the vehicle starting, including the jerk and the clutch slip time, are provided here. Based on the analyses of the simulation results and driver’s experiences, a fuzzy controller is designed to control the clutch engagement. Simulation results verify its value.
文摘The simulation model of the E car HS2000 including the permanent magnetic direct current motor with the augment magnet winding is constructed based on tests in order to simulate the synthetic performance of the electric car. The performance of E car HS2000 is analyzed by means of modeling and programming according to data acquired during tests. The simulation results show that the performance of E car HS2000 is successfully predicted and the model and the corresponding simulation software are feasible for simulating E cars. They can be used as effective tools for analyzing the performance parameters as well as specifications of E cars during prototype stage.
基金Supported by the National Natural Science Foundation of China under Grant Nos.60634010 and 60776829the State Key Laboratory of Rail Traffic Control and Safety (Contract No.RCS2008ZZ001 and RCS2010ZZ001),Beijing Jiaotong University
文摘Based on optimM velocity car-following model, in this paper, we propose a new railway tramc model for describing the process of train movement control. In the proposed model, we give an improved form of the optimal velocity function V^opt, which is considered as the desired velocity function for train movement control under different control conditions. In order to test the proposed model, we simulate and analyze the trajectories of train movements, moreover, discuss the relationship curves between the train allowable velocity and the site of objective point in detail. Analysis results indicate that the proposed model can well capture some realistic futures of train movement control.
基金Projects(60404003,11202230)supported by the National Natural Science Foundation of China
文摘The application of new-designed levitation controller requires extensive validation prior to enter into commercial service. However, huge mounts of approximations and assumptions lead the theoretical analysis away from the engineering practice. The experimental methods are time-consuming and financial expensive, even unrealizable due to the lack of suitable sensors. Numerical simulations can bridge the gap between the theoretical analysis and experimental techniques. A complete overall dynamic model of maglev levitation system is derived in this work, which includes the simple-supported bridges, the calculation of electromagnetic force with more details, the stress of levitation modules and the cabin. Based on the aforementioned model, it shows that the inherent nonlinearity, inner coupling, misalignments between the sensors and actuators, and self-excited vibration are the main issues that should be considered during the design process of controller. Then, the backstepping controller based on the mathematical model of the module with reasonable simplifications is proposed, and the stability proofs are listed. To show the advantage of controller, two numerical simulation experiments are carried out. Finally, the results illustrating closed-loop performance are provided.
基金Projects(90820302, 60805027, 61175064) supported by the National Natural Science Foundation of ChinaProject(2011ssxt231) supported by the Master Degree Thesis Innovation Project Foundation of Central South University, China+1 种基金Project(200805330005) supported by the Research Fund for the Doctoral Program of Higher Education, ChinaProject(2011FJ4043) supported by the Academician Foundation of Hunan Province, China
文摘A trajectory generator based on vehicle kinematics model was presented and an integrated navigation simulation system was designed.Considering that the tight relation between vehicle motion and topography,a new trajectory generator for vehicle was proposed for more actual simulation.Firstly,a vehicle kinematics model was built based on conversion of attitude vector in different coordinate systems.Then,the principle of common trajectory generators was analyzed.Besides,combining the vehicle kinematics model with the principle of dead reckoning,a new vehicle trajectory generator was presented,which can provide process parameters of carrier anytime and achieve simulation of typical actions of running vehicle.Moreover,IMU(inertial measurement unit) elements were simulated,including accelerometer and gyroscope.After setting up the simulation conditions,the integrated navigation simulation system was verified by final performance test.The result proves the validity and flexibility of this design.
基金supported by National Natural Science Foundation of China under Grant Nos. 60634010 and 60776829Key Technology Research of Train Control System,and Urban Rail Transit Automation and Control Beijing Municipal Government Key Laboratory
文摘In this paper, we propose a new cellular automata model to simulate the railway traffic at station. Based on NaSch model, the proposed station model is composed of the main track and the siding track. Two different schemes for trains passing through station are considered. One is the scheme of "pass by the main track, start and stop by the siding track". The other is the scheme of "two tracks play the same role". We simulate the train movement using the proposed model and analyze the traffic flow at station. The simulation results demonstrate that the proposed cellular automata model can be successfully used for the simulations of railway traffic. Some characteristic behaviors of railway traffic flow can be reproduced. Moreover, the simulation values of the minimum headway are close to the theoretical values. This result demonstrates the dependability and availability of the proposed model.
文摘Abstract: The current method to solve the problem of active suspension control for a vehicle is often dealt with a quarter-car or half-car model. But it is not enough to use this kind of model for practical applications. In this paper, based on considering the influence of factors such as, seat and passengers, a MDOF(multi-degree-of-freedom) model describing the vehicle motion is set up. The MODF model, which is 8DOF of four independent suspensions and four wheel tracks, is more applicable by comparison of its analysis result with some conventional vehicle models. Therefore, it is more suitable to use the 8DOF full-car model than a conventional 4DOF half-car model in the active control design for car vibration. Based on the derived 8DOF model, a controller is designed by using LQ (linear quadratic ) control theory, and the appropriate control scheme is selected by testing various performance indexes. Computer simulation is carried out for a passenger car running on a road with step disturbance and random road disturbance expressed by Power Spectral Density (PSD). Vibrations corresponding to ride comfort are derived under the foregoing road disturbances. The response results for uncontrolled and controlled system are compared. The response of vehicle vibration is greatly suppressed and quickly damped, which testifies the effect of the active suspension. The results achieved for various controllers are compared to investigate the influence of different control schemes on the control effect.
基金Supported by the National Natural Science Foundation of China under Grant No. 70901006Research Foundation of Beijing Jiaotong University under Grant Nos. 2011JBM158, 2011JBM162Research Foundation of State Key Laboratory of Rail Traffic Control and Safety under Grant Nos. RCS2009ZT001, RCS2010ZZ001
文摘Based on the discrete time method, an effective movement control model is designed for a group of high- speed trains on a rail network. The purpose of the model is to investigate the specific traffic characteristics of high-speed trains under the interruption of stochastic irregular events. In the model, the high-speed rail traffic system is supposed to be equipped with the moving-block signalling system to guarantee maximum traversing capacity of the railway. To keep the safety of trains' movements, some operational strategies are proposed to control the movements of trains in the model, including traction operation, braking operation, and entering-station operation. The numerical simulations show that the designed model can well describe the movements of high-speed trains on the rail network. The research results can provide the useful information not only for investigating the propagation features of relevant delays under the irregular disturbance but also for rerouting and reseheduling trains on the rail network.
文摘Based on an improved three-dimensional wheel-rail contact trace algorithm and a new model of wheel-rail contact force, wheel-rail derailment dynamical model is established on China Railways High-speed(CRH) vehicle and developed in MATLAB software, which is called dynamical derailment system for CRH (DDSCRH). Analyzed on dynamical derailment process of high speed vehicle by DDSCRH, the critical position on chmb wheel and influence factors on lateral force for derailment are obtained. Finally, high-speed vehicle dynamical simulation is verified on DDSCRH by comparing with the existing results of the line test.
基金Supported by the National Natural Science Foundation of China (No.50705008)
文摘In order to improve the yaw stability of the vehicle with active front steering system, an adaptive PID-type fuzzy control scheme is designed to make the yaw rate tracking the desired values as close as possible. A 2-DOF vehicle model with active front steering is built firstly, and then the fuzzy PID controller is designed in detail. The simulation investigations of the yaw stability with different steering ma- neuvers are performed. The simulation results show the effectiveness of the fuzzy PID controller for improving the vehicle's yaw stability.
文摘Automotive manufacturing is complex and includes the coordination of design in the manufacturing system. The manufacturing approaches over the past few years, disassembly have been a key issue, and it seems that simulation models are usually tailored to address a narrow set of industrial issues. This paper describes the development of the production line in the automobile manufacturing system through design, operation, and maintenance, based on multi-objectives of Algorithm and Simulation Model called MOA-SM. The both models are being developed at three different levels: the production line in the body and assembly shop, supply chain, and the production plan. The optimization tries to involve more objectives to solve the issues in manufacturing system. A solution that may optimize one performance measure may deteriorate since other performance solutions are difficult. The resulting algorithms are comparable to the simulation and multi-object in terms of success rate, assembly times, peak forces, moments, and have assembly times superior to those of a benchmark blind search algorithm.
基金Supported by the National Basic Research Program of China under Grant No.2012CB725400the National Natural Science Foundation of China under Grant No.71222101+1 种基金the Research Foundation of State Key Laboratory of Rail Traffic Control and Safety under Grant No.RCS2014ZT16the Fundamental Research Funds for the Central Universities No.2015YJS088,Beijing Jiaotong University
文摘This paper aims to present a simulation model for heterogeneous high-speed train traffic flow based on an improved discrete-time model(IDTM).In the proposed simulation model,four train control strategies,including departing strategy,traveling strategy,braking strategy,overtaking strategy,are well defined to optimize train movements.Based on the proposed simulation model,some characteristics of train traffic flow are investigated.Numerical results indicate that the departure time intervals,the station dwell time,the section length,and the ratio of fast trains have different influence on traffic capacity and train average velocity.The results can provide some theoretical support for the strategy making of railway departments.
基金the National Natural Science Foundation of China(No.51278429)the Key Laboratory of Road and Traffic Engineering of the Ministry of Education,Tongji University(No.K201207)the Program for New Century Excellent Talents in University(No.NCET-13-0977)
文摘Gipps' model, a well-known safe distance car-following model, has a very strict restriction on the car-following behavior that the following vehicle has to maintain the exact safe distance to the leading vehicle to avoid rear crash. However, this restriction is not consistent with the real traffic condition. Due to that, an enhanced safe distance car-following model is proposed first, and then calibrated and evaluated using the field data. Furthermore, the simulation is conducted to analyze the characteristics of the new model. The results of evaluation and simulation illustrate that the proposed model has higher simulation accuracy than the original Gipps' model, and can reproduce the stable flow and shock wave phenomena that are very common in real traffic.Moreover, the simulation results also prove that the enhanced model can better stabilize the traffic flow than Gipps' model.
基金Supported by the National Basic Research Program of China under Grant No. 2012CB725400the National Natural Science Foundation of China under Grant No. 71131001-1the Research Foundation of State Key Laboratory of Rail Traffic Control and Safety under Grant No. RCS2011ZZ003, Beijing Jiaotong University
文摘Based on the Nagel-Schreckenberg model, we propose a new cellular automata model to simulate the urban rail traffic flow under moving block system and present a new minimum instantaneous distance formula under pure moving block. We also analyze the characteristics of the urban rail traffic flow under the influence of train density, station dwell times, the length of train, and the train velocity. Train delays can be decreased effectively through flexible departure intervals according to the preceding train type before its departure. The results demonstrate that a suitable adjustment of the current train velocity based on the following train velocity can greatly shorten the minimum departure intervals and then increase the capacity of rail transit.