# Comprehensive Review of Traffic Modeling: Towards Autonomous Vehicles
## 9 Future Directions and Emerging Trends  
The future directions and emerging trends in cooperative autonomous vehicle (AV) systems emphasize advanced communication technologies and collaborative strategies. The feasibility of using reconfigurable intelligent surfaces (RISs) to enhance cooperative driving was explored by [PERSON] et al. [298], who highlighted the potential of RISs to improve signal reflections in challenging vehicular environments. Similarly, the integration of mmWave communications with RISs to support dependable coordination in AV platoons was discussed by [PERSON] and colleagues in another study, demonstrating the benefits of RISs for wireless coverage extensions [299]. In the realm of unmanned aerial vehicles (UAVs), a comprehensive review by authors in IEEE Transactions on intelligent transportation systems underscores the need for high-speed communication links, flexible control strategies, and efficient collaborative decision-making algorithms to improve the autonomy and reliability of UAV swarms [300]. These studies collectively point to the importance of robust communication frameworks and intelligent surface technologies in the advancement of cooperative AV systems. The future directions and emerging trends in urban air mobility (UAM) integration emphasize the development of robust infrastructures, advanced communication technologies, and regulatory frameworks. [PERSON] [301] discussed the vision and challenges of UAM, highlighting the need for real-time autonomous scheduling, dynamic route planning, and airspace traffic management to support sustainable urban mobility. [PERSON] et al. [302] focused on the integration of Unmanned Aircraft Systems (UASs) with existing air traffic management frameworks, emphasizing the importance of communications, navigation, and surveillance technologies for safe operations. A comprehensive study by another group of researchers outlined the optimization techniques to achieve environmental, sustainability, or climate change mitigation goals [303]. [PERSON] et al. [304] discussed the role of the Internet of Things (IoT) in UAM, proposing an IoT-supported network to address control, safety, and communication challenges. These studies collectively underscore the importance of integrating advanced technologies and developing comprehensive regulatory frameworks to ensure the successful implementation of UAM. The future directions and emerging trends in autonomous freight transport highlight significant transformations driven by advanced technologies and innovative business models. [PERSON] et al. [305] examined the impact of technologies like AI, IoT, and autonomous vehicles on logistics, emphasizing their potential to enhance efficiency but also posing challenges such as job displacements and supply chain vulnerabilities. [PERSON] [306] discussed the influence of automated and autonomous vehicles on freight transport, highlighting the need for new frameworks to manage these advancements. [PERSON] and [PERSON] [307] introduced the Autonomous Transfer Hub Network (ATHN) model, which optimizes freight operations by integrating autonomous and human-driven trucks. Lastly, [PERSON] and [PERSON] [308] discussed digitalization trends in freight transport, categorizing them into connecting, collaborating, and capitalizing technologies, which drive significant changes in logistics systems. The future directions and emerging trends in policy and regulatory considerations for autonomous vehicles (AVs) are critical for their successful deployment and integration into society. [PERSON] et al. [309] discussed the shift in liability from human drivers to AVs, highlighting the need for states to redefine what constitutes a driver. They emphasized the importance of creating consistent regulatory objectives to manage this transition. [PERSON] and [PERSON] [310] analyzed the regulatory frameworks in ASEAN countries, comparing them with those in Europe to suggest effective legal approaches for AV integration. [PERSON] et al.