Vehicle Moving Research Articles

Application of Adjoint Aerodynamics Optimization for a High-Speed Vehicle Moving in a Tube

Application of Adjoint Aerodynamics Optimization for a High-Speed Vehicle Moving in a Tube

A Rapid Solver for the Prediction of Flow-Field of High-Speed Vehicle Moving in a Tube

High-speed vehicles traveling in a tube with pressures similar to those experienced by aircraft at their maximum altitude are presented. Although the concept resembles Hyperloop, the pressure level investigated here is much higher and safer than that suggested by Hyperloop, and, therefore, the system design is markedly different. Calculating a vehicle’s aerodynamic performance in the initial design stages requires low-budget computational tools to enable iterative design processes. This study presents an algorithm for rapid flow-field prediction based on a one-dimensional Reimann solution, including viscosity and heat transfer effects. The flow-field is divided into near- and far-fields, where the near-field represents the solution directly around the vehicle. The far-field demonstrates the impact of the vehicle’s motion on the vehicle’s flow-field upstream and downstream. Two-dimensional URANS models are compared to the current numerical scheme. The developed algorithm analyzes the flow-field and the propagation of pressure waves along the tube to simulate the vehicle’s movement. The one-dimensional model shows the robustness and predictability of the near and far flow-fields. The results from the developed scheme provide good agreement, with less than a few percent deviations, compared to CFD simulations but with significantly lower computational resources.

Intelligent Vehicle Moving Trajectory Prediction Based on Residual Attention Network

Skilled drivers have the driving behavioral characteristic of pre-sighted following, and similarly intelligent vehicles need accurate prediction of future trajectories. The LSTM (Long Short-Term Memory) is a common model of trajectory prediction. The existing LSTM models pay less attention to the interactions between the target and the surrounding vehicles. Furthermore, the impacts on future trajectories of the target vehicle have also barely been a focus of the current models. On these bases, a Residual Attention-based Long Short-Term Memory (RA-LSTM) model was proposed, an interaction tensor based on the surroundings of the target vehicle at the predictive moments was constructed and the weight coefficients of the interaction tensor for the surrounding vehicles relative to the target vehicle were calculated and re-programmed in this study. The proposed RA-LSTM model can implicitly represent the different degrees of influence of the surrounding vehicles on the target vehicle; the probability distributions of the future trajectory coordinates of the target vehicle is predicted based on the extracted interaction features. The RA-LSTM model was tested and verified in multiple scenarios by using the NGSIM (next generation simulation) public dataset, and the results showed that the prediction accuracy of the proposed model is significantly improved compared with the current LSTM models.

The High-Speed Railway Bridges Under Vehicle Moving Load And Near Fault Seismic Ground Motions – Review.

All-time needs of maintenance of high-speed train system and its infrastructure safety are must all over the world. Nowadays, for the smooth running of HSR trains, most of the country depends on the HSR bridge structures, but there is still a lack of understanding of the behavior of structures under various factors like seismic and high speed moving load effects. To study the dynamic behavior of HSR bridges, it is important to consider the interaction of moving vehicle – Bridge structure – Ground surface showing that the different parameters involved in understanding the response of the structure. The main motivation of this study is to initiate a better understanding of the various parameters effects by those seismic and moving vehicles over the dynamic behavior of the HSR bridges. The effects of forwarding directivity pulses were considered to understand the behavior of HSR bridges against near-fault earthquakes, which can make a substantial impact on the seismic demand capacity of the moving vehicles and structures. The effects of high-speed moving vehicles over the HSR bridges to understanding the parameters involved in the dynamic behavior of the coupled system. This literature review can help the beginners and who initiate the study based on the dynamic behavior of high-speed railway bridges and their components under seismic and moving load effects.

Analysis of Vehicle Moving Parameters in Various Road Conditions

The safety of road users is one of the priority issues raised by those involved in vehicle design, latest passive and active safety systems, traffic organization or driver education. Nowadays, an important road safety problem is the behaviour of drivers in emergency situations. In order to measurably estimate the driving quality, parameters such as velocity, acceleration, the way and frequency of using the control pedals are quite often used. This article describes how to assess driver's behaviour based on measurements taken on the road. The frequency of different acceleration ranges during the vehicle drive was determined based on the results obtained. For the arbitrarily adopted acceleration range of - 0.5 - 0.5 m/s2, the driver's working time was over 77 percent on average, with the difference varying significantly between different route sections. Similarly, the study compares the driving times for other ranges of acceleration.

Numerical and Analytical Study of a Battery Powered Vehicle Moving in a Vacuum Tunnel

The present work focuses on an aerodynamic and heat transfer study of a battery powered vehicle moving in a vacuum tunnel. The conducted research was based on analytical analysis and numerical calculations. Four different vacuum levels in the tunnel were considered—100 Pa, 1 kPa, 10 kPa and 100 kPa—and two distinct velocities of the vehicle—125 and 166 m/s—to address subsonic and supersonic conditions. It allowed defining limitations related to vacuum transportation in terms of velocity of the vehicle and a blocking ratio of the tunnel. Power consumption and drag coefficient for the considered tunnel pressures were analyzed. The cooling analysis of the batteries by passing air was performed numerically and analytically in the function of flow conditions in the tunnel. It gave some insight into main problems related to cooling of the batteries under low pressure and possible directions to solve it. It was shown that the proposed analytical model compared satisfactorily with the numerical results.

Effect of the Number of Vehicle Moving Load Axles on Peak Impact Factor and Response Factors of Simply Supported Bridges

Effect of the Number of Vehicle Moving Load Axles on Peak Impact Factor and Response Factors of Simply Supported Bridges

차량의 이동 방향과 거리 기반의 그리디 애니캐스트 포워딩 프로토콜

차량의 이동 방향과 거리 기반의 그리디 애니캐스트 포워딩 프로토콜

A Dynamic Thresholding Technique In Spatially Co-Located Objects Mining From Vehicle Moving Data

Co-location pattern discovery is intended towards the processing data with spatial contexts to discover classes of spatial objects that are frequently located together. The existing moving vehicle location prediction technique not analyses the moving vehicles co-location instance. So, we improve the previous technique process by mining spatially co-located moving objects using spatial data mining techniques. Initially, the neighbour relationship is computed by the prim's algorithm. After that, the candidate co-locations are pruned according to the presence of candidate co-location in the input data and the final stage of co-location instances selection is performed by compute neighbourhood and node membership functions. The values obtained using neighbourhood membership function is compared with the dynamic threshold values. The co-location instances are selected which satisfy the dynamic threshold value. Moreover, the proposed co-location pattern mining with dynamic thresholding technique is compared with the existing co-location pattern mining technique.

Analysis on Inverse Problem of Lunar Roving Vehicle Moving Trajectory with Continuous Curvature

Analysis on Inverse Problem of Lunar Roving Vehicle Moving Trajectory with Continuous Curvature

The Using of Vehicle Moving Simulation to Proposal of Construction Work

The Using of Vehicle Moving Simulation to Proposal of Construction Work

Risk Simulation Analysis of Vehicle Moving on Curved Sections based on Driver Braking

Risk Simulation Analysis of Vehicle Moving on Curved Sections based on Driver Braking

Optimization of Delivery Route for Multi-Vehicle under Time Various and Unsymmetrical Forward and Backward Vehicle Moving Speed

Optimization of Delivery Route for Multi-Vehicle under Time Various and Unsymmetrical Forward and Backward Vehicle Moving Speed

Stator Resistance Estimation for 4WD Electric Vehicle Moving in South East of Algeria in the Saharan Regions

The Direct Torque control is one of the modest control used in urban electric vehicle control. This kind of control is based on Stator resistance coefficient. This stator resistance coefficient is influenced with the temperature variation. In our present work, many more tests were carried on urban electric vehicle moved in Saharan area. Our example is examined in one the hottest regions in the Algerian Saharan region, exactly in Bechar city which located in the south east of Algeria. So the basic idea of this paper is the estimation of the stator resistance variations of the Four wheels electric vehicle moving in the high temperature conditions. The aim objective of this work is to study the behavior of an 4 wheels drive electric vehicle (4WDEV) controlled by the direct torque control in a Saharan city taking into account the Stator Resistance variation. A PI controller is used to adjust the 4WDEV stator resistance. The performances of the proposed strategy controller give a satisfactory simulation results. This actual studies make sure the safety and the stability of this vehicle moving in Saharan regions where, the future industrial's vehicle must take into considerations the of stator resistance variations into design.

An Efficient Vehicle Routing Heuristic for Various and Unsymmetric Forward and Backward Vehicle Moving Speed

An Efficient Vehicle Routing Heuristic for Various and Unsymmetric Forward and Backward Vehicle Moving Speed

Dynamic Analysis of Railway Vehicle Moving through Bridge with Varying Velocity

A dynamic model of vehicle-bridge interaction is presented considering the railway vehicle moving through bridge with varying velocity. Assuming the vehicle has a constant acceleration, the motion equations of coupled vehicle-bridge system were deduced based on DAlemberts principle and theory of Euler beam. Dynamic responses of system were analyzed both cases of the acceleration and drag acceleration for a moving car. Results show that the amplitudes of vibration of the system will enlarge sharply with the acceleration of vehicle increasing, and the maximum of responses occur when the vehicle moving at the middle point of bridge. In addition, the stiffness coefficient is one of the key factors to affect on dynamic responses of system. Generally, the suitable rigidity of structure is much important to decrease the responses and suppress the vibration of system.

The Simulation Research of Damping Characteristics for the Underwater Vehicle Moving under or Exceeding Water

The vehicle may vibrate when it moves under or exceeding water. This vibration will interact with the flow filed around to form a fluid-structure interactiondynamics system. In this paper, the numerical simulation of a cylinder in the process of moving under or exceeding water with ABAQUS and FLUENT is presented. Simultaneously, the first three damping ratio of the system are obtained by damping identification. For different density, viscosity and velocity of water, model separately to get the impact of each factor. Besides, the continuous process of exceeding water has been discretized to obtaindifferent oscillating curvesat different positions with respect to the water,and then the change of the damping ratio is presented. Thus the damping characteristics of the system in the water-exit process have been obtained approximately.

Response of a Maglev Vehicle Moving on a Two-Span Flexible Guideway

AbstractThis paper is intended to present a preliminary framework for dynamic interaction analysis of a maglev (magnetically levitated) vehicle running on a two-span guideway using a comprehensive iterative approach. A maglev vehicle with electrodynamic suspension (EDS) system is simplified as a two degrees-of-freedom (2-DOF) maglev oscillator tuned by a PID (Proportional-Integral-Derivative) controller. The guideway is modeled as a two-span continuous beam with uniform section. Two sets of equations of motion are written, with the first set for the guideway and the second set for the maglev oscillator traveling on the guideway through a motion-dependent magnetic force. To achieve the stable levitation gap for a maglev vehicle moving on a flexible guideway, Ziegler-Nicholas (Z-N) tuning rules are used to determine the tuning parameters of the PID controller. Numerical simulations demonstrate that the levitation gap affects the dynamic response of the maglev vehicle while little influence on the guideway response since the inertial force of the moving maglev vehicle is much lower than its static load.

Closure to “ Bridge Vibrations due to Vehicle Moving over Rough Surface ” by Mahil J. Inbanathan and Martin Wieland (September, 1987, Vol. 113, No. 9)

Closure to “ <i>Bridge Vibrations due to Vehicle Moving over Rough Surface</i> ” by Mahil J. Inbanathan and Martin Wieland (September, 1987, Vol. 113, No. 9)

Discussion of “ Bridge Vibrations due to Vehicle Moving over Rough Surface ” by Mahil J. Inbanathan and Martin Wieland (September, 1987, Vol. 113, No. 9)

Discussion of “ <i>Bridge Vibrations due to Vehicle Moving over Rough Surface</i> ” by Mahil J. Inbanathan and Martin Wieland (September, 1987, Vol. 113, No. 9)