Connected and automated vehicle (CAV) technologies have great potential to improve road safety. However, an emerging type of mixed traffic flow with human-driven vehicles (HDVs) and CAVs has also arisen in recent years. To improve the overall safety of this mixed traffic flow, a novel car-following model is proposed to control the driving behaviors of the above two types of vehicles in a platoon from the perspective of a mechanical system, mass-spring-damper (MSD) system. Furthermore, a quantitative index is proposed by incorporating the psychological field theory into the MSD model. The errors of spacing and speed in the car-following processes can be expressed as the accumulation of the virtual total energy, and the magnitude of the energy is used to reflect the danger level of vehicles in the mixed platoon. At the same time, the optimization model of minimum total energy is solved under the constraints of vehicle dynamics and the mechanical characteristics of the MSD system, and the optimal solutions are used as the parameters of the MSD car-following model. Finally, a mixed platoon composed of 3 CAVs and 2 HDVs without performing lane changing is tested using the driver-in-the-loop test platform. The test results show that, in the mixed platoon, CAVs can optimally adjust the intervehicle spacing by making full use of the braking distance, which also provides sufficient reaction time for the driver of HDV to avoid rear-end collisions. Furthermore, in the early stage of the emergency braking, the spacing error is the dominant factor influencing the car-following behaviors, but in the later stage of emergency braking, the speed error becomes the decisive factor of the car-following behaviors. These results indicate that the proposed car-following model and quantitative index are of great significance for improving the overall safety of the mixed traffic flow with CAVs and HDVs.

中文翻译：

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基于质量-弹簧-阻尼器模型的混合交通排的风险建模和量化

联网和自动车辆（CAV）技术在改善道路安全方面具有巨大潜力。然而，近年来也出现了一种新兴类型的混合交通流，其中包括人力车辆（HDV）和CAV。为了提高这种混合交通流的总体安全性，提出了一种新型的汽车跟随模型，以从机械系统质量弹簧阻尼器（MSD）的角度控制上述两种类型的车辆在排中的驾驶行为。系统。此外，通过将心理场理论纳入MSD模型来提出定量指标。跟车过程中间距和速度的误差可以表示为虚拟总能量的累积，并且能量的大小用于反映混合排中车辆的危险程度。同时，在车辆动力学和MSD系统机械特性的约束下，求解了最小总能量的优化模型，并将最优解作为MSD跟随模型的参数。最后，使用“在环驾驶员测试”平台测试由3个CAV和2个HDV组成的混合排而不执行换道。测试结果表明，在混合排中，CAV可以通过充分利用制动距离来最佳地调节车距，这也为HDV驾驶员提供了足够的反应时间，避免了追尾事故。此外，在紧急制动的早期，间距误差是影响汽车跟随行为的主要因素，但在紧急制动的后期，速度误差成为汽车追随行为的决定性因素。这些结果表明，提出的跟车模型和量化指标对提高CAV和HDV混合交通流的整体安全性具有重要意义。