Cooperative Adaptive Cruise Control (CACC) system is an expansion to existing Adaptive Cruise Control (ACC) control strategy by using wireless communication with preceding vehicles (V2V) and/or the infrastructure (I2V). Both multi vehicle V2V data and I2V infrastructure data are within the scope of this document. When V2V data is used CACC can enable shorter time gaps and more accurate gap control, which can help increase traffic throughput and reduce fuel consumption. It can also receive data from the infrastructure, such as recommended speed and time gap setting, to improve traffic flow and safety.
This document addresses two types of Cooperative Adaptive Cruise Control (CACC): V2V, and I2V. Both types of CACC system require active sensing using for example radar, lidar, or camera systems. The combined V2V and I2V CACC is not addressed in this document. The following requirements are addressed in this document:
— classification of the types of CACC;
— definition of the performance requirements for each CACC type;
— CACC state transitions diagram;
— minimum set of wireless data requirements;
— test procedures.
— does only longitudinal vehicle speed control;
— uses time gap control strategy similar to ACC;
— has similar engagement criteria as ACC.
Coordinated strategies to control groups of vehicles, such as platooning, in which vehicle controllers base their control actions on how they affect other vehicles, and may have a very short following clearance gap are not within the scope of this document. CACC system operates under driver responsibility and supervision.
This document is applicable to motor vehicles including light vehicles and heavy vehicles.