ROV attitude control based on multi-motor cooperative propulsion北大核心CSCD

[目的]为了提高遥控水下航行器(ROV)在复杂水下环境中的姿态控制性能,开展多电机协同推进的ROV姿态控制研究。[方法]首先,针对多电机系统的结构和算法,分别提出一种基于PID速度补偿器的偏差耦合结构和一种新型非奇异终端滑模控制(SMC)算法,并设计一种新颖的基于多电机协同推进的ROV姿态控制方法;然后,建立ROV的运动学和动力学模型,开展推进器组推力建模分析、解耦简化ROV动力学模型研究;最后,设计一种ROV滑模姿态控制器。[结果]仿真结果表明,所提的结构和算法可提高多电机系统的抗干扰性、同步性和快速响应能力,进而提高ROV姿态控制系统的稳定性与鲁棒性。[结论]所提方法可为ROV姿态控制提供一种新的可用方案。     

多类型信息下的网络交通流演化模型

交通信息发布机构提供描述信息和规范信息给不同的出行者，描述信息接收者依据信息和经验更新路径行程时间认知，根据认知选择路径；规范信息接收者仅根据经验更新认知.规范信息遵从者选择推荐路径，非遵从者依据认知选择路径.两类信息遵从率都取决于信息准确度.依据非线性动力学理论分析了模型性质，研究表明，模型不动点存在但是不一定唯一，不动点状态与信息混合使用情况有关.数值试验结果表明，模型不动点与随机用户均衡点不同，以恰当比例混合使用两类信息可提高交通流稳定性.     

Economic and ecological optimization of electric bus charging considering variable electricity prices and CO2eq intensities

In many cities, diesel buses are being replaced by electric buses with the aim of reducing local emissions and thus improving air quality. The protection of the environment and the health of the population is the highest priority of our society. For the transport companies that operate these buses, not only ecological issues but also economic issues are of great importance. Due to the high purchase costs of electric buses compared to conventional buses, operators are forced to use electric vehicles in a targeted manner in order to ensure amortization over the service life of the vehicles. A compromise between ecology and economy must be found in order to both protect the environment and ensure economical operation of the buses.In this study, we present a new methodology for optimizing the vehicles’ charging time as a function of the parameters CO_2eq emissions and electricity costs. Based on recorded driving profiles in daily bus operation, the energy demands of conventional and electric buses are calculated for the passenger transportation in the city of Aachen in 2017. Different charging scenarios are defined to analyze the influence of the temporal variability of CO_2eq intensity and electricity price on the environmental impact and economy of the bus. For every individual day of a year, charging periods with the lowest and highest costs and emissions are identified and recommendations for daily bus operation are made. To enable both the ecological and economical operation of the bus, the parameters of electricity price and CO₂ are weighted differently, and several charging periods are proposed, taking into account the priorities previously set. A sensitivity analysis is carried out to evaluate the influence of selected parameters and to derive recommendations for improving the ecological and economic balance of the battery-powered electric vehicle.In all scenarios, the optimization of the charging period results in energy cost savings of a maximum of 13.6% compared to charging at a fixed electricity price. The savings potential of CO_2eq emissions is similar, at 14.9%. From an economic point of view, charging between 2 a.m. and 4 a.m. results in the lowest energy costs on average. The CO_2eq intensity is also low in this period, but midday charging leads to the largest savings in CO_2eq emissions. From a life cycle perspective, the electric bus is not economically competitive with the conventional bus. However, from an ecological point of view, the electric bus saves on average 37.5% CO_2eq emissions over its service life compared to the diesel bus. The reduction potential is maximized if the electric vehicle exclusively consumes electricity from solar and wind power.     

面向新型混合交通流的智能交叉口网络布局优化

考虑网联自动驾驶车辆(Connected Autonomous Vehicle, CAV)应用先进的车联网与自动驾驶技术，可以采用智能交叉口的组织形式，大幅提升交叉口的通行效率，为降低CAV与人工驾驶车辆(Human-driven Vehicle, HV)混行条件下城市交通系统的整体出行成本，提出智能交叉口在城 市交通网络中的布局优化问题，建立数学优化模型并求解。首先，基于对两类车辆行驶特性的分析，建立混合用户均衡模型，描述CAV与HV的路径选择行为；其次，从交通规划者的角度，以系统最优为目标，整合混合用户均衡模型，建立面向新型混合交通流的智能交叉口网络布局优化模型，并利用改进的遗传算法求解；最后，选取Sioux-Falls交通网络作为案例分析，验证模型与算法的有效性，并研究CAV渗透率变化对优化结果的影响。研究表明，智能交叉口在城市路网中的合理规划极大地提高了新型混行场景下城市交通系统的出行效率，同时，大幅降低了由于网联自动 驾驶单方面技术优势带来的CAV与HV的出行效率差距，增进了出行公平性。     

基于车辆自动定位数据的有轨电车运行效率分析与应用

结合有轨电车线路的现有车辆自动定位数据,分析有轨电车运行效率及其相关影响因素。其中,影响因素从站台、路段、交叉口3个方面进行考虑。定性分析了不同站台型式、站台位置、交叉口类型的属性特征,并量化不同路段的路段长度、所包含的交叉口个数,同时考虑了交叉口控制策略对有轨电车运行时间的影响。以某已运营的有轨电车线路为例,通过建立多元线性回归模型,从不同层面探究不同因素对已运营有轨电车线路运行效率的影响。最后用模型对有轨电车新建线路的运行效率进行预测,并提出建议。     

S^2 BHCA Multiple AUVs cooperation oriented control architecture

Oceanographic survey, or other similar applications should be the applications of multiple AUVs. In this paper, the skill ＆ simulation based hybrid control architecture （S^2BHCA） as the controller＇s design reference was proposed. It is a multi-robot cooperation oriented intelligent control architecture based on hybrid ideas. The S^2BHCA attempts to incorporate the virtues of the reactive controller and of the deliberative controller by introducing the concept of the ＂skill＂. The additional online task simulation ability for cooperation is supported, too. As an application, a multiple AUV control system was developed with three ＂skills＂ for the MCM mission including two different cooperative tasks. The simulation and the sea trials show that simple task expression, fast reaction and better cooperation support can be achieved by realizing the AUV controller based on the S^2BHCA.     

列车通信网络研究现状及展望

介绍了列车通信网络的主要任务和列车通信网络的拓扑结构,阐述了列车通信网络(TCN)的发展历程及目前国内外列车通信网络的发展现状,并展望了列车通信网络技术的发展趋势。     

横甩研究概况与发展方向

介绍了非线性动力学理论在船舶横甩研究中的应用，总结了近年来横甩研究的主要方法和结论，最后指出了横甩问题尚需深入研究的几个方面。     

柴油机主副连杆机构动力分析

认为主、副连杆是两个独立运动的刚体，它们通过关节销连接起来．通过坐标转换关系，研究主副连杆机构平面运动规律，导出了主副活塞运动的速度、加速度以及主、副连杆不动、摆动的加速度、角加速度．基于刚体平面运动理论，对V型柴油机主副连杆机构进行动力学分新，给出了计算公式，便于编程计算。     

摩擦焊接工艺在全浮式汽车半轴制造中的应用

介绍了国内汽车半轴生产所采用的三种型式——锻造式半轴、分体式半轴及摩擦焊接式半轴。对摩擦焊接式半轴的生产工艺、摩擦焊接结合机理、生产设备及应用特点等作了介绍，为我国中小型汽车企业在工艺水平方面提供借鉴。