In this article, we study the optimal coordination of automated vehicles at intersections. The problem can be stated as an optimal control problem (OCP), which can be decomposed as a bi‐level scheme composed by one nonlinear program (NLP) which schedules the access to the intersection and one OCP per vehicle which computes the appropriate vehicle commands. We discuss a practical implementation of the bi‐level controller where the NLP is solved with a tailored semi‐distributed sequential quadratic programming (SQP) algorithm that enables distribution of most computation to the vehicles. Results from an extensive experimental campaign are presented, where the bi‐level controller and the semi‐distributed SQP are implemented on a test setup consisting of three automated vehicles. In particular, we show that the vehicle‐level controller can enforce the scheduled intersection access beyond the accuracy admitted by the sensor system, and that the bi‐level controller can handle large perturbations and large communication delays, which makes the scheme applicable in practical scenarios. Finally, the use of wireless communication introduces delays in the outer control loop. To allow faster feedback, we introduce a real‐time iteration (RTI) like variation of the bi‐level controller. Experimental and simulated results indicate that the RTI‐like variation offers comparable performance using less computation and communication.

中文翻译：

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半分布式顺序二次规划方法在交叉路口自动车辆最佳协调的实验验证

在本文中，我们研究交叉路口的自动驾驶车辆的最佳协调。该问题可以说成是最优控制问题（OCP），可以分解为一个由一个非线性程序（NLP）组成的双层方案，该程序计划对交叉路口的访问，而每辆车则由一个OCP来计算适当的车辆命令。我们讨论了双层控制器的实际实现，其中使用定制的半分布式顺序二次规划（SQP）算法解决了NLP，该算法可将大部分计算分配给车辆。展示了来自广泛实验活动的结果，其中双层控制器和半分布式SQP在由三个自动车辆组成的测试装置上实施。尤其是，我们显示，车辆高度控制器可以强制执行计划的交叉路口访问，而超出传感器系统允许的精度，并且该双层高度控制器可以处理较大的扰动和较大的通信延迟，这使得该方案适用于实际场景。最后，无线通信的使用在外部控制环路中引入了延迟。为了获得更快的反馈，我们引入了实时迭代（RTI），例如双层控制器的变化形式。实验和模拟结果表明，类似RTI的变体使用较少的计算和通信即可提供可比的性能。这使得该方案适用于实际情况。最后，无线通信的使用在外部控制环路中引入了延迟。为了获得更快的反馈，我们引入了实时迭代（RTI），例如双层控制器的变化形式。实验和模拟结果表明，类似RTI的变体使用较少的计算和通信即可提供可比的性能。这使得该方案适用于实际情况。最后，无线通信的使用在外部控制环路中引入了延迟。为了获得更快的反馈，我们引入了实时迭代（RTI），例如双层控制器的变化形式。实验和模拟结果表明，类似RTI的变体使用较少的计算和通信即可提供可比的性能。