Investigating the Effect of Wireless Communication-Enabled Adaptive Cruise Control on Traffic Smoothing, 10-R9802Printer Friendly Version
Inclusive Dates: 04/01/08 04/01/09
Background - In the last decade, vehicle technology has been moving toward developing intelligent vehicles, or "smart cars." These vehicles provide technologically advanced active and passive safety, control and communications systems. These systems increase the safety, mobility, control and connectivity of vehicles and transportation systems. This movement is on-going through public and private efforts internationally. SwRI is actively involved in the research and development of the enabling technologies for intelligent and autonomous vehicles through several internal research and commercial projects.
Automobile platforms today implement cruise control through various sensors around the vehicle. Sensors such as radar, sonar and laser provide a passive and vehicle centric approach to adaptive cruise control and vehicle platoons or teams. Such systems require the driver to be actively involved with the system control. In addition, platoons of vehicles are not able to cooperatively operate along a roadway. A wireless system or network, enabling vehicle-to-vehicle communications, may pass vehicle-based information to accomplish such an activity. A byproduct of "platooning," or adaptive cruise control, may be traffic smoothing; however, the magnitude of the effect is unknown. Advanced notification of increased or decreased speed zones may reduce the traffic caterpillar effect.
Approach - The research conducted on this program will analyze the ability of a cooperative system, which utilizes both vehicle-to-vehicle communications and bi-directional communications between the vehicle and infrastructure, to improve traffic smoothing. Emphasis is placed on the investigation of the benefits of a sensorless adaptive cruise control enabled through wireless communications. The key research components are a comparative analysis of the impacts to the caterpillar effect of traffic-jam and convoy operations, and a performance analysis of the implementations operating in the same environment. An extension of the concept will be to process infrastructure-based information to formulate a higher level of roadway situational awareness. This will allow the platoon to operate within limits based on infrastructure information and real-time roadway conditions.
Accomplishments - The team has been working on the on-board vehicle processes for interfacing with the vehicle platform. These processes take different forms because the project is using three different vehicle platforms: traditional driven, semi-controlled and autonomous vehicle. The on-board processes provide the desired level of control that is required for each vehicle platform. In addition, the project team is integrating the ASN.1 data encoding schemes for the roadside infrastructure applications. The roadside infrastructure will transmit roadway information that will further determine the vehicle's and the team's operational characteristics.