论文标题
在动态环境中自动化车辆安全性和性能的实时轨迹计划
Real-time trajectory planning for automated vehicle safety and performance in dynamic environments
论文作者
论文摘要
在具有静态和移动障碍的环境中,对高性能自动化车辆的安全轨迹计划是一个挑战性的问题。挑战的一部分是开发一种可以实时解决的公式,同时包括以下规格:最低时间到目标,动态车辆模型,最小控制工作,静态和移动的障碍物避免,同时对速度和转向的同时优化,以及短期执行。本文介绍了一种非线性模型预测基于控制的轨迹计划公式,该计划是针对大型高速无人接地车辆量身定制的,其中包括上述规格。本文还评估了NloptControl与Knitro非线性编程问题求解器实时解决此配方的能力; NLOPTCONTROL是我们的开源,基于直接交付的最佳控制问题求解器。使用各种规格测试了该公式。特别是,一项与执行范围和障碍速度有关的参数研究表明,当计划者具有较小的执行范围($ \ leq0.375 \; s $)时,不需要安全障碍物规范,并且障碍物的移动缓慢($ \ leq leq leq leq leq2.11 \ frac {m} {m} {s} {s}。但是,当障碍物移动更快时,需要进行移动的避免障碍规格,并且该规范将整体安全性提高了$ 6.73 $($ p = 2.2 \ times10^{ - 16} $),而在大多数情况下,则增加了求解时间。总体而言,结果表明,(1)高性能自动化车辆的安全轨迹规划师应包括上述整个规格集,除非静态或低速环境允许不太全面的计划者; (2)NloptControl可以实时解决该公式。
Safe trajectory planning for high-performance automated vehicles in an environment with both static and moving obstacles is a challenging problem. Part of the challenge is developing a formulation that can be solved in real-time while including the following set of specifications: minimum time-to-goal, a dynamic vehicle model, minimum control effort, both static and moving obstacle avoidance, simultaneous optimization of speed and steering, and a short execution horizon. This paper presents a nonlinear model predictive control-based trajectory planning formulation, tailored for a large, high-speed unmanned ground vehicle, that includes the above set of specifications. This paper also evaluates NLOptControl's ability to solve this formulation in real-time in conjunction with the KNITRO nonlinear programming problem solver; NLOptControl is our open-source, direct-collocation based, optimal control problem solver. This formulation is tested with various sets of the specifications. In particular, a parametric study relating execution horizon and obstacle speed, indicates that the moving obstacle avoidance specification is not needed for safety when the planner has a small execution horizon ($\leq0.375\;s$) and the obstacles are moving slowly ($\leq2.11\frac{m}{s}$). However, a moving obstacle avoidance specification is needed when the obstacles are moving faster, and this specification improves the overall safety by a factor of $6.73$ ($p=2.2\times10^{-16}$) without, in most cases, increasing the solve-times. Overall, the results indicate that (1) safe trajectory planners for high-performance automated vehicles should include the entire set of specifications mentioned above, unless a static or low-speed environment permits a less comprehensive planner; and (2) NLOptControl can solve the formulation in real-time.