TIER IV tests autonomous semi-trailer with Yamato and Mitsubishi Fuso

TOKYO, March 9, 2026 /PRNewswire/ -- TIER IV, the pioneering force behind open-source software for autonomous driving, has completed proof of concept tests for long-haul autonomous trucking with Yamato Transport Co., Ltd. (Yamato Transport) and Mitsubishi Fuso Truck and Bus Corporation (MFTBC), as part of a Japanese government initiative. The tests evaluated vehicle performance, safety protocols and operational workflows, with customer freight transported on a semi-trailer truck equipped with Level 2+ technology. The data and operational insights gathered will be used to refine autonomous driving technology, with the ultimate goal of integrating Level 4 trucks into Yamato Group's long-haul transportation routes.

Overview

• Period: February 16-20, 2026
• Route: Haneda Chronogate Base (Tokyo) – Kansai Gateway Base (Osaka). Two round trips (four legs) of the about 500-km route were completed. The truck operated at Level 2+ for 100 km on the Shin-Tomei Expressway between two service areas in Shizuoka Prefecture.

Evaluation scope

• Vehicle performance and safety
  • Collection of trailer motion data, including sway and articulation trajectories.
  • Performance verification, tracking hands-off duration and lane-keeping accuracy.
  • Analysis of surrounding conditions, driver decision-making criteria and other factors linked to manual interventions.
• Travel time
  • Confirmation that schedules were maintained during Level 2+ driving as reliably as during manual operations, without delays.
• Operational workflows
  • Trials of systems that automate parts of the pre-trip inspection, such as tire pressure checks.
  • Remote monitoring of vehicle status and surroundings to prepare for future Level 4 operations.

Driver testimonial

"There was a bit of a learning curve at first, but once I understood how the system behaves, I felt at ease. Looking ahead, I hope autonomous trucks become a reliable partner for us, helping to maintain our hauling capacity."

Videos and photos

Multimedia assets are available for download below.

• Videos
  • Long-haul operations using Yamato Transport's semi-trailer truck (Copyright Yamato Transport)
  • Development of the tractor designed for Level 2 automated driving functions by TIER IV and MFTBC (Copyright MFTBC)
• Photos
  • Long-haul operations with the semi-trailer truck (Copyright Yamato Transport)