# Enhancing Freeway Traffic Capacity: The Impact of Autonomous Vehicle Platooning Intensity
## 5 Conclusions  
This paper proposes a theoretical model to discuss the capacity of heterogeneous saturated flow. The platooning intensity, which represents the willingness of connected and autonomous vehicles to form platoons, has been taken into consideration. The relationship between platooning intensity and CAVs penetration rate was evaluated by considering the number of vehicles in the fleet. Numerical analysis was conducted, which further improved the proposed theoretical model. Finally, microscopic simulation has been used to verify the accuracy of the proposed model. The simulated outcomes closely align with the theoretical predictions, providing compelling evidence for the soundness of the proposed theoretical model. The primary contribution of this study is that it reveals the intrinsic relationship between MPR and platooning intensity. On this basis, an improved formula has been given that enables the calculation of the maximum theoretical capacity of mixed flow, accounting for the platooning intensity of CAVs. An additional interesting finding has emerged, showing that as the number of vehicles within a fleet increased, the weighted average of the platoon intensity gradually converged towards the market penetration rate (MPR). The formulation has provided valuable insights into traffic performance within a heterogeneous flow context. Both speed and MPR have exhibited significant impacts on capacity; however, these impacts were non-linear. Specifically, the slope of the speed-affected curve gradually decreased, while the slope of the MPR-affected curve gradually increased. Moreover, the influence of MPR on theoretical capacity intensified with increasing speed. In our study, we primarily focus on the impact of connected and autonomous vehicles (CAVs) on platooning behavior and capacity. However, we acknowledge that user behavior, including drivers of traditional vehicles, plays a significant role in maintaining appropriate headway. Respecting the desired headway for users driving traditional vehicles relies on a combination of factors, including traffic regulations, driver awareness, and individual driving habits. While our methodology assumes a certain level of compliance with headway requirements, it is important to note that actual user behavior may vary. To address this aspect, it is better to emphasize the need to consider user behavior and its potential influence on headway compliance. Furthermore, it would be useful to discuss the importance of traffic education, enforcement of traffic regulations, and public awareness campaigns to encourage responsible driving practices that promote safe and efficient headway management. Policy implications derived from this study provide valuable guidance to decision makers and transport providers. These include incorporating infrastructure elements for CAVs, implementing adaptive traffic management systems, establishing comprehensive regulatory frameworks, prioritizing public engagement and education, fostering collaboration among stakeholders, and developing robust data management practices. Decision makers should consider these implications to create efficient, sustainable, and safe transportation systems that leverage the potential of CAV technology. This involves integrating dedicated lanes and communication infrastructure, optimizing signal timings and lane assignments, addressing safety and privacy through regulations, raising public awareness and trust, promoting collaboration, and implementing responsible data collection and usage practices. By considering these policy implications, decision makers can drive innovation and make informed choices to enhance transportation networks. Traffic capacity has been analyzed from both macroscopic and microscopic perspectives in this study. The findings presented in this paper significantly contribute to the comprehension of the effects of CAV maneuvers on traffic flow. However, there are several areas of potential expansion that should be considered in future research.