论文标题

在城市和高速公路驾驶场景中,车辆避免和碰撞的车辆风险评估和控制

Vehicle Risk Assessment and Control for Lane-Keeping and Collision Avoidance in Urban and Highway Driving Scenarios

论文作者

Fahmy, Hazem, Ghany, Mohamed A. Abd El, Baumann, Gerd

论文摘要

本文研究了一种符号数值方法,可以优化车辆的自动驾驶和避免碰撞的轨道。新方法使用经典的成本函数定义,将车辆动态状态的基本方面纳入了轮胎滑动角度的位置,方向,时间抽样和约束。优化过程可以最大程度地减少成本函数,并通过改变转向和破坏幅度来同时确定最佳轨道。车辆的当前速度仅限于最大速度,因此可以稳定地搜索最佳轨道。障碍物的参数定义为低速和高速模拟产生了灵活的环境。影响最少的影响优化变量可确保最佳结果稳定,直接生成。通过当前在最佳轨道上控制车辆的新方法,我们能够自主在低阶多项式近似的任意轨道上自主移动车辆。优化方法还能够处理各种不同的障碍物和相应的最佳光滑障碍路径。这些计算证明了在正常运行中对四轮车辆的有效控制,并在不断可区分的障碍物避免轨道的情况下进行了出色的避免障碍。使用3m/s,6m/s,76m/s,10m/s,12m/s和18m/s的车辆速度进行仿真测试。在高级车辆的速度下,仅数学方法不够,并且需要对轮胎进行机械干预作为控制滑动角的免费零件。结果表明,在大多数测试的方案中,成本函数的平均收敛速度对零率成功达到了相当高的速度。

This article examines a symbolic numerical approach to optimize a vehicle's track for autonomous driving and collision avoidance. The new approach uses the classical cost function definition incorporating the essential aspects of the dynamic state of the vehicle as position, orientation, time sampling, and constraints on slip angles of tires. The optimization processes minimize the cost function and simultaneously determine the optimal track by varying steering and breaking amplitudes. The current velocity of the vehicle is limited to a maximal velocity, thus, allowing a stable search of the optimal track. The parametric definition of obstacles generates a flexible environment for low and high speed simulations. The minimal number of influential optimization variables guarantees a stable and direct generation of optimal results. By the current new approach to control a vehicle on an optimal track, we are able to autonomously move the vehicle on an arbitrary track approximated by low order polynomials. The optimization approach is also able to deal with a variety of different obstacles and the corresponding optimal smooth obstacle path. The computations demonstrate the effective control of a four wheel vehicle in normal operation and exceptional obstacle avoidance with continuously differentiable obstacle avoidance tracks. Simulation tests are done using vehicle's velocities of 3m/s, 6m/s, 7.6m/s, 10m/s, 12m/s, and 18m/s. At higher vehicle's velocities, a mathematical-only approach is not sufficient and a mechanical intervention for tires is needed as a complimentary part to control the slip angle. The results shows that the cost function reached a considerably high average convergence-to-zero rate success in most of the tested scenarios.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源