On the experimental analysis of single input single output control of yaw rate and sideslip angle

Electric vehicles with individually controlled drivetrains allow torque-vectoring, which improves vehicle safety and drivability. This paper investigates a new approach to the concurrent control of yaw rate and sideslip angle. The proposed controller is a simple single input single output (SISO) yaw rate controller, in which the reference yaw rate depends on the vehicle handling requirements, and the actual sideslip angle. The sideslip contribution enhances safety, as it provides a corrective action in critical situations, e.g., in case of oversteer during extreme cornering on a low friction surface. The proposed controller is experimentally assessed on an electric vehicle demonstrator along two maneuvers on surfaces with significantly varying tire-road friction coefficient. Different longitudinal locations of the sideslip angle used as control variable are compared during the experiments. Results show that: i) the proposed SISO approach provides significant improvements with respect to the vehicle without torque-vectoring, and the controlled vehicle with a reference yaw rate solely based on the handling requirements for high-friction maneuvering; and ii) the control of the rear axle sideslip angle provides better performance than the control of the sideslip angle at the center of gravity.     

The use of equilibrium network models in logistics management: With application to the U.S. coal industry

This paper discusses the use in logistics management of the freight network equilibrium model, developed in Harker and Friesz (1985a, b), called the Generalized Spatial Price Equilibrium Model, or GSPEM. After this discussion, computational techniques for solving this model are presented. The application of GSPEM to the analysis of the U.S. coal economy is then presented and future extensions of this line of research are discussed.     

Ballast water treatment ashore — Better for the environment and for seafarers

After a brief overview of the International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM Convention), 2004, the status of ratification and its applicability to ships the main methods for ballast water treatment required by the BWM Convention are introduced. Port-based reception and treatment facilities would offer many benefits compared to treatment of ballast water on board — shore-based facilities would be more efficient and provide both economical and environmental advantages. The choice to impose the ballast water treatment obligations on the ships and their crews may have been the solution of least resistance, but it may also be the solution, which represents the least efficiency and the greatest overall cost as well as a potential for negative consequences for the crew responsible for ballast water management.     

BP对油轮的检查

<正>英国石油公司(BP)非常关注船舶质量,希望通过审查,降低风险,降低事故率。为此,BP在世界上建立了很多检查网点,如新加坡、上海、墨尔本、伦敦,鹿特丹、休斯顿以及芝加哥等,都设有专门机构。同时,BP还有一支由70名经过认证的检查员组成的检查队伍,他们在全世界范围内进行检查,然后提交相关报告。     

碧海之上 挑衅骄阳 航海防晒攻略

夏季是乘风破浪的最佳季节，热爱冒险刺激的你渴望出海扬帆，注重生活品质的你又需要保护好皮肤——航海防晒，就成为了航行之前，你不可不做的”功课”。只需要一点点时间和心思，将以下7点身体力行，你就可以尽享在碧波蓝天下，驯服烈日的快乐。     

Peak period tolls: Precepts and prospects

This article presents the economic rationale for road pricing and provides some scale on the magnitude of peak period tolls that might be justified. It discusses the impacts of such tolls on congestion, air quality and economic development and suggests a long term strategy towards areawide implementation of peak period pricing. It discusses current trends which are increasing the likelihood for implementation of congestion pricing and toll roads in the future. In particular, it discusses some aspects of the 1991 Intermodal Surface Transportation Efficiency Act (ISTEA) which will eliminate some of the current restraints on congestion pricing and toll highways.Abbreviations ETC Electronic toll collection - FHWA Federal Highway Administration - HOV High occupancy vehicle - ISTEA Intermodal Surface Transportation Efficiency Act - LOS Level of service - TCM Transportation control measure - V/C Volume-to-capacity ratio - VMT Vehicle mile(s) of travel - vphpl Vehicles per hour per lane     

On the Experimental Analysis of Integral Sliding Modes for Yaw Rate and Sideslip Control of an Electric Vehicle with Multiple Motors

With the advent of electric vehicles with multiple motors, the steady-state and transient cornering responses can be designed and implemented through the continuous torque control of the individual wheels, i.e., torque-vectoring or direct yaw moment control. The literature includes several papers on sliding mode control theory for torque-vectoring, but the experimental investigation is so far limited. More importantly, to the knowledge of the authors, the experimental comparison of direct yaw moment control based on sliding modes and typical controllers used for stability control in production vehicles is missing. This paper aims to reduce this gap by presenting and analyzing an integral sliding mode controller for concurrent yaw rate and sideslip control. A new driving mode, the Enhanced Sport mode, is proposed, inducing sustained high values of sideslip angle, which can be limited to a specified threshold. The system is experimentally assessed on a four-wheel-drive electric vehicle. The performance of the integral sliding mode controller is compared with that of a linear quadratic regulator during step steer tests. The results show that the integral sliding mode controller significantly enhances the tracking performance and yaw damping compared to the more conventional linear quadratic regulator based on an augmented singletrack vehicle model formulation.