四轮独立转向-独立驱动车辆转向模式动态切换原理与方法研究

项目名称： 四轮独立转向-独立驱动车辆转向模式动态切换原理与方法研究

项目编号： No.51505290

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 来鑫

作者单位： 上海理工大学

项目金额： 20万元

中文摘要： 四轮独立转向-独立驱动车辆除了继承分布式驱动电动车辆的优点外，机动性及冗余控制自由度更高，具备直行、斜行、前轮/后轮/四轮/原地转向等多种转向模式，应用领域与前景广阔。目前该车辆转向模式切换是在停车后进行，严重影响行驶安全性、机动性及智能性。鉴于此本项目提出“充分利用车辆冗余控制自由度，科学规划及控制各车轮的运动轨迹，实现转向模式不停车动态切换”的科学设想。据车辆运动/动力学建立转向模式动态切换数学模型，结合车辆位姿模型分析动态切换原理；构建优化目标泛函(如能量最优、时间最优等)、约束条件及边界条件，分别求解各转向模式动态切换时车辆及各车轮最优运动轨迹，并对切换过程进行仿真及动力学评价，探索动态切换过程与方法；设计车辆运动协调控制与车轮轨迹跟踪相结合的控制策略，并通过实车实验验证研究结论的有效性。本项目旨在提高该车辆行驶安全性、机动性及智能性，为其工程应用及实际道路行驶提供理论与技术基础。

中文关键词： 四轮独立转向—独立驱动车辆；转向模式动态切换；最优运动规划；轨迹跟踪控制；协调控制

英文摘要： The four wheel independent steering and independent drive (4WIS-4WID) vehicle have higher maneuverability and redundancy control degrees of freedom, besides the advantages of distributed drive electric vehicle. The 4WIS-4WID vehicle can steer in several modes, such as straight moving, oblique moving, front wheel steering, rear wheel steering, four wheel steering, point-turn motion, so it have vast application field and prospect. However, the vehicle must be completely still when the steering mode switching, a lot of problems such as driving safety and moving mobility are more and more serious, especially in the environment of high speed and intensive. In view of this, this project put forward the scientific ideas that can be expressed as “using the redundant control of the vehicle fully, planning and optimizing the trajectory of each wheel, realizing the steering mode dynamic switching in no parking condition”. Steering mode dynamic switching mathematical model will be established based on vehicle kinematics and dynamics，combined with the vehicle pose model, dynamic switching principle will be described; Several typical objective functions (e.g. energy optimization, time optimization, etc.), dynamic constraints and boundary condition are built, then the optimal trajectory of each wheel will be solved respectively in these optimization objectives when each steering mode dynamic switching, and simulation and dynamic evaluation will be done, the dynamic switching process and method will be explored later. A composite control strategy called “vehicle coordinated motion control and wheels trajectory tracking” will be designed. Through theoretical analysis, simulation and experimental research, a new method of steering mode dynamic switching base on vehicle optimal motion planning and control is built. The purpose of this project is to improve the driving safety, mobility and intelligence of 4WIS-4WID vehicle, and the research achievements provide a solid theoretical and technical foundation for the engineering application and the actual road running.

英文关键词： four wheel independent steering and drive vehicle;steering mode dynamic swiching ;optimal motion panning ;trajectory tracking control;coordination control