MHI to Test Autonomous Vehicle Ramp Merging Technology in Tokyo

Mitsubishi Heavy Industries Machinery Systems, Ltd. (MHI-MS) is partnering with Tokyo’s Metropolitan Expressway Co., Ltd. To develop and test technology designed to support the safe merging of autonomous vehicles onto high-traffic expressways. A demonstration experiment is scheduled for September to November 2026, focusing on a challenging section of the Tokyo Metropolitan Expressway.

Addressing Urban Expressway Challenges

The initiative directly addresses the complexities of integrating self-driving cars into one of the world’s most congested urban highway systems [1]. The trial will take place near the Yoyogi entrance (inbound) of Metropolitan Expressway Route 4 (Shinjuku Line). This location was specifically chosen due to its demanding merging conditions, including a short merging section, a continuous curve, and differences in elevation between the on-ramp and the main expressway lanes [1], [2].

Building on Previous Success

MHI-MS was selected for the project following a competitive review process prompted by a call for research partners from the Metropolitan Expressway Co., Ltd. [1]. The company’s prior success implementing a Merging Support Information System on the Shin-Tomei Expressway was a key factor in the decision [2]. This earlier system demonstrated the feasibility of infrastructure-based support for smoother and safer merging maneuvers.

Leveraging Existing Technologies

MHI-MS plans to utilize its expertise in sensing and communication technologies, originally developed for toll collection and Electronic Toll Collection (ETC) systems, to create the roadside-to-vehicle infrastructure necessary for autonomous driving support [2]. The project emphasizes the importance of infrastructure in relaying real-time information from the road environment to autonomous systems, extending beyond the capabilities of onboard vehicle sensors.

Industry Trends and Future Expansion

This collaboration aligns with the broader industry trend towards Connected, Autonomous, Shared, and Electric (CASE) technologies [2]. MHI-MS intends to expand the deployment of this merging support technology to a wider range of roadway operators throughout Japan, building on the knowledge gained from this demonstration project [2], [3].

Mitsubishi Heavy Industries (MHI) Group is a leading industrial group spanning energy, smart infrastructure, industrial machinery, aerospace and defense [3].