Accuracy Improvement of Vehicular Collision Avoidance Support System (VCASS) for the next generation ITS

In recent years, researches and developments on ITS are carried out to solve many problems in road traffic. IVC (inter-vehicular communications) is the key technology to realize the next generation ITS (Tokuda et al., 2002 and Morioka et al., 2000). Vehicles install telecommunication equipments, and exchange information directly with each other. The authors have developed vehicular collision avoidance support system (VCASS) based on IVC in order to prevent a vehicular accident beforehand. The system grasps the relative location of vehicles by exchanging the GPS information in each vehicle. Then the system warns drivers if there is a danger of collision. In this paper we propose two schemes in order to improve the accuracy of VCASS. We evaluate the performance of conventional collision judgment algorithm and the proposal scheme for VCASS. We have verified the effectiveness of the new VCASS in typical road environments.