Development of an adaptive active trailer steering system for long combination vehicles

长途联合车辆(LCV)在加拿大各地的高速公路上越来越多地使用。一辆轻型货车由一辆牵引车和两辆挂车组成，每辆挂车的长度为16.2米，车辆总长度可达40米。轻型货车的两种主要配置为A型和B型列车。与拖拉机/半挂车组合相比，使用LCV可以使行驶里程减少45%，燃料消耗和温室气体排放减少30%，道路磨损减少40%。然而，A型列车的横向稳定性较差，B型列车的操纵性较差，轻型货车的方向性能不佳可能导致交通事故。现有高速公路匝道/立交的几何特征是在20世纪50年代至70年代设计的，没有充分考虑LCV的性能衡量标准。由于方向性能较差，轻型货车只能在指定的安大略省高速公路路段上行驶。加拿大漫长而严酷的冬季模式进一步降低了LCV的安全性。我们相信，为LCV开发自适应主动拖车转向(AATS)系统将对加拿大人产生多重影响，使卡车运输业和道路系统受益于这些车辆的积极影响，例如，更低的运输成本、更轻的环境影响和更少的道路损害，同时减轻交通事故增加和拥堵的不利风险。该项目旨在开发AATS技术，以改善B型列车的低速操纵性，并增强A型列车的高速横向稳定性。在我们以往对挂车主动转向研究的基础上，AATS系统将在高可靠性、对工况变化的适应性和容错设计方面具有显著的特点。我们将通过开展相关研究来开发创新的AATS技术：1)探索主动挂车转向的自适应和容错控制；2)基于驾驶员-硬件在环实时仿真，制作AATS原型并验证技术。这项研究将解决阻碍AATS技术成为市场产品的问题。

Long combination vehicles (LCVs) are increasingly used on highways across Canada. An LCV consists of a tractor and two trailers, the length of each trailer is 16.2 m, and the total length of the vehicle can be 40 m. Two main configurations of LCVs are A- and B-train. Compared with a tractor/semi-trailer combination, the use of an LCV can result in 45% reduction in mileage travelled, 30% drop in fuel consumption and greenhouse gas emissions, and 40% decrease in road wear. However, A-trains exhibit low lateral stability, B-trains show poor maneuverability, and the unsatisfactory directional performance of LCVs may lead to traffic accidents. The geometric features of existing highway ramps/interchanges were designed during the 1950s-70s without adequately considering the performance measures of LCVs. Due to the poor directional performance, LCVs are only allowed to travel on designated Ontario highway sections. Canada's long and severe winter patterns further degrade LCV safety. We believe that developing an adaptive active trailer steering (AATS) system for LCVs will have a multifold impact on Canadians by allowing the trucking industry and road systems to benefit from the positive effects of these vehicles, e.g., lower shipping costs, lighter environmental impact, and reduced road damage, while mitigating the adverse risks of increased traffic accidents and congestion. The proposed project aims at developing the AATS technology to improve the low-speed maneuverability of B-trains and enhance the high-speed lateral stability of A-trains. Built upon our previous investigations on active trailer steering, the AATS system will be developed with distinguished features in terms of high reliability, adaptability to operating condition variation, and fault-tolerant design. We will develop the innovative AATS technology by performing interrelated investigations: 1) exploring adaptive and fault-tolerant control of active trailer steering; and 2) fabricating AATS prototypes and validating the technology based on driver-hardware-in-the-loop real-time simulation. The research will resolve the problems that are impeding the AATS technology from becoming a marketable product.