Current Issue : April-June Volume : 2023 Issue Number : 2 Articles : 5 Articles
Traffic flow optimization and trajectory guidance in merging zones have significant implications for improving capacity and reducing time consumption. The development of V2X communication provides new insights to solve this problem by tackling the information and releasing trajectories schemes. Therefore, this paper aims to discuss the trajectory management in the merging zone for ACC vehicles. A vehicle dispatching and car-following model is proposed to generate steady traffic flow first. An algorithm framework for consecutive traffic flow is presented with the idea of FIFO rules. Then, a two-step method for an individual vehicle is discussed in detail to compute a trajectory. The first step is to select and determine the priority of the optional gaps. The next step is to verify the options’ feasibility, decide on the target gap, and output the trajectories to merge successfully. Numerical experiments validate that the proposed method guarantees safe driving and provides relatively smooth trajectories to the vehicles. Furthermore, increased capacity and higher velocity are observed in a comparative experiment. The cooperative optimization algorithm could be applied efficiently in practice and benefit from its rapid response and low computation complexity....
The electric vehicle (EV) industry has made significant progress but, in many markets, there are still barriers holding back its advancement. A key issue is the anxiety caused to the drivers by the limited range of current EV models and the inadequate access to charging stations in long-distance trips, as is the case on highways. We propose an intuitive multi-criteria approach that optimally places EV charging stations on highways that (partially) lack such points. The approach, which is applied in an iterative fashion to dynamically evaluate the alternatives, considers a set of practical criteria related to the traffic intensity and the relative location of the charging stations with interchanges, major cities, and existing stations, thus supporting decisions in a pragmatic way. The optimal locations are determined by taking into consideration constraints about the EV driving range and installation preferences to improve the operation of the highway while ensuring reasonable cost of investment. The proposed approach is showcased in the Egnatia Motorway, the longest highway in Greece that runs a total of 670 km but currently involves a single EV charging point. Our findings illustrate the utility of the proposed approach and highlight its merits as a decision-support tool....
The research consisted of simulating the movement of a single vehicle in relation to the swarm leader on a square-shaped path, taking into account measurement errors characteristic of typical cheap navigation devices and the hydroacoustic system. The research showed that these methods allow for estimating position coordinates with an accuracy of about 0.5 m (RMS) in the case of a calibrated navigation system and about 3.6 m (RMS) in the case of a non-calibrated navigation system. It also showed that it can provide a higher accuracy of estimating position coordinates in terms of abeam angles of the swarm leader (relative bearing equal to approximately ±90◦), as well as while ensuring minimizing systematic errors values and proper estimation of mean errors values concerning course and speed measurements....
The development of the electric mobility market in cities is becoming more and more important every year. With this development, more and more electric scooters are appearing in cities. Currently, the restrictions that result from the upcoming trends are reducing the number of vehicles powered by combustion engines in favor of vehicles equipped with electric motors. Considering the number of electric vehicles, the dominant type is an electric scooter. The aim of this article is to determine the CO2 that is emitted into the atmosphere by using this type of vehicle. The main suppliers of this type of vehicle in cities are shared mobility systems. To recognize the research gap, consisting of the lack of CO2 emissions of an electric scooter type vehicle, studies were carried out on the energy consumption of an electric scooter and CO2 emissions, which were calculated based on the CO2 emission value needed to produce a given energy value kWh. The plan of the research performed was developed on the basis of the D-optimal plan of the experiment, thanks to which the results could be saved in the form of mathematical models based on formulas....
The improvement of handling and stability performance of Distributed Drive Electric Vehicle (DDEV) is analyzed, visualized, and designed by proposing and deploying the mixed control strategies in this paper including Direct Yaw Control (DYC), Antislip Regulation (ASR) and a novel Dual-mode Switching Control (DMSC). First, by drawing the phase trajectory stability domain, the vehicle stability limit boundary can be determined, which provides the basis for the lateral stability constraint of the vehicle. Then, the practicability and real time visualization of driving efficiency and timeliness of DDEV is achieved to reduce the margin of error for the desired torque value by employing the DYC strategy which uses a fuzzy PID algorithm. Furthermore, the ASR strategy which adopts the optimal slip rate algorithm to determine the requirement of desired torque value based on the different road conditions is used to reduce slip phenomenon effectively and to maintain handling control of DDEV. In response to different scenes especially conflict and coexistence between DYC and ASR, the DMSC strategy is applied to find a more suitable slip rate range by using the root mean square error method (REME). Finally, the cosimulation platform of ADAMS/Car and MATLAB/ Simulink is built to simulate the mixed control strategies by integrating DYC, ASR, and DMSC. The simulation results show that the DMSC can effectively prevent DDEV from entering the dangerous limit driving state when turning and driving. The strategy has a more significant control effect needed to meet the requirements of the driving safety of the vehicle and handling stability. The DMSC is adopted and downloaded into the electronic control unit of our student type formula vehicle called Flash V6 which was designed and developed by a team of students, the ZUST ATTACKER Team....
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