CLAIMING an industry first, Toshiba has developed an ATO system for operation at Grade of Automation 2.5 (GoA2.5) that does not require the installation of lineside equipment to transmit data between track and train and determine the train’s position.

The new system has been developed jointly with Japan’s Nagano Electric Railway, where overnight testing took place between August 2023 and February 2024 to verify basic operation on urban sections of the network.

The test train operated with an attendant in the lead car, who under GoA2.5 is not required to be a qualified driver but can initiate emergency braking and undertake other safety-related procedures such as passenger evacuation.

The ATO system determines the position of the train using GNSS satellite location data and an inertial measurement unit (IMU), and uses a stereo camera and Lidar for obstacle detection.

Position information is checked against a track map database to control acceleration, deceleration and stopping of the train. During testing, the train was brought to a stand with an accuracy of within 50cm.

In addition, the onboard attendant was notified of a simulated obstacle on the track and brought the train to a stand manually.

Obstacles were successfully detected up to 200m ahead of the train when operating at 70km/h at night, compared with the 130m limit of human vision in darkness, Toshiba says. To improve obstacle detection on curves, an auxiliary headlight was installed on the train.

The company says that the trials confirmed the difficulty of detecting obstacles by camera alone under environmental conditions such as backlighting and oncoming lights, and work is continuing to improve detection at night and on curves.

Toshiba is now developing a system that can stably detect obstacles up to 300m away under such conditions, and has produced a prototype combining laser-based Lidar and camera technology.

It will also further enhance the ATO system by enabling it to automatically select the optimum sensor for the position of the train, taking terrain and weather conditions into account.

Toshiba believes that the new system can be installed on wide range of rolling stock for full-scale ATO, while avoiding the cost of installing and maintaining additional lineside equipment.

It says that it will provide solutions to meet the individual requirements of operators, supporting a move to GoA3 or higher grades of automation in future.

Development of the new ATO system and the trials on the Nagano Electric Railway have been funded with a railway technology development grant from Japan’s Ministry of Land, Infrastructure, Transport and Tourism.