Assurance technology for the mode change of autonomous decentralised train control system

Since 1981, the conventional automatic train control (ATC) system has been used on the Yamanote and Keihin-Tohoku lines, which are the most crowded commuter routes in Tokyo. The conventional ATC is a ground oriented system with cumbersome wayside equipment. Therefore, they have several problems and an obstacle to improvements in transportation service. The D-ATC system with on-board intelligence was introduced, an 'autonomous decentralised' technology, and with this technology was realised a new concept. Following introduction to Yamanote and Keihin-Tohoku several years ago, D-ATC system will be introduced into Negishi Line next. There are two problems in system construction: these are 'Coexistence of heterogeneous systems' and 'autonomous on-board mode change'. We clarified these problems and solved them by using the assurance technology. In this paper, we will outline the D-ATC system and these solution techniques.