| Demand for highway travel continues to grow as population increases. The United States is home to the largest motor vehicle market in the world with over 250 million registered motor vehicles according to a 2012 report by U.S. Department of Transportation. Filling roads with vehicles causes traffic congestion which has adverse impact on society such as traffic delays, increased fuel consumption and pollution, road rage, etc. Intelligent Transportation System (ITS) which consists of electronics, communications, or information processing used singly or in combination, tries to improve the efficiency or safety of a surface transportation system.;Collaborative driving is a component of ITS aiming at building autonomous vehicles that can cooperate using communication. First we focused on designing a car-following model for ACC/CACC vehicles. In particular, we designed an enhanced CACC longitudinal controller that consists of three modes, namely, speed control, gap control, and collision avoidance modes. We analyzed local and string stability theoretically and using our developed simulator, VENTOS, we evaluated the performance of our CACC controller under different scenarios, including worst-case stopping, different time gap settings, and under realistic stop-and-go traffic.;In the second work, we developed a platoon management protocol based on VANET and CACC vehicles that uses three basic platoon maneuvers: merge, split and lane-change. These three basic maneuvers can be used to accomplish various platoon operations, such as vehicle entry, platoon leader leave, and follower leave. Our protocol is based on V2V communication with single-hop beacon messages as well as event-driven messages to coordinate the maneuvers with other neighboring vehicles. CACC car-following model based on one-vehicle look-ahead communication and platoon management protocol are implemented in VENTOS in order to study CACC platooning performance.;In the third work, we focused on designing an interactive intersection that supports multi-modal traffic, namely, pedestrians, bicyclists, and motor vehicles. Vehicles, pedestrians and cyclists are given an active role and they can contribute to the detection process by giving inputs to the system which in turn increases the detection accuracy. This vision is easily realizable due to advances in miniaturization of sensors and communication chips and is referred to as Internet of Things (IoT).;We also performed a study of the security vulnerabilities and risks associated with deploying VANET communication in connected vehicle streams to achieve automated sensing and control such as CACC. We consider various types of what-if scenarios when communications between autonomous vehicles participating in CACC are compromised. In addition, we examine existing countermeasures, explore limitations of these methods and possible ways to alleviate negative effects. Using our developed simulator, VENTOS, we also simulated the impact of application and network layer attacks by a malicious insider on the performance of a CACC vehicle stream. |
