Autonomous driving demonstration test held in Tokyo

The history and practical applications of autonomous driving began in 2000 in the United States. The first autonomous racing conducted by the U.S. Defense Advanced Research Projects Agency (DARPA) got attention. That race became a big trigger for the mass production of LiDAR units that could shoot lasers in a 360-degree direction. The researchers moved to major companies of IT and autonomous parts companies after the event and they started to make practical applications in autonomous driving. China, following the United States, has begun a government program to develop autonomous driving. Japan, meanwhile, has been working on these projects since 2014 as part of its Cross-ministerial Strategic Innovation Promotion Program (SIP).

I participated in an autonomous driving demonstration test that was held in Tokyo in September 2020. According to Mr. Kuzumaki, the SIP-adus program director at Toyota Motor Corporation Japan, the program is underway despite the delays caused by the COVID-19. The demonstration test presented concrete examples of technology that shares traffic conditions on main lines with DSRC and technology that shares vehicle location information measured by magnetic markers with autonomous driving car through communication. It was confirmed that the SIP, which is in its second phase is focused on V2X, which aims to make road-to-vehicle communication practical.

  760MHz Dedicated Short Range Communications (DSRC)

The autonomous driving car that can communicate wirelessly with the DSRC antennas installed in the test area is a modified Lexus RH450h that was built by Kanazawa University under contract to SIP. For image recognition, a monocular cameras, LiDAR units and 77 GHz millimeter wave radars are mounted on the car. For satellite positioning it uses a PT-G1 autonomous navigation unit equipped with a GNSS receiver from Furuno Electric Co. There are 30 760 MHz DSRC antennas in Tokyo for autonomous driving applications. At this demonstration test site, DSRC antennas are transmitting the colors and lighting times of traffic lights. According to the people involved with SIP, "In some situations, such as when there is backlighting, it is difficult to recognize the colors of traffic lights with a camera Therefore DSRC at intersections is an essential element in the practical application of autonomous driving. After the experiment using DSRC, we observed a demonstration test to acquire vehicle location information with magnetic markers.

 Magnetic marker

The vehicle used in the vehicle location recognition demonstration test was a modified version of the SORA fuel cell electrified vehicle bus, which was jointly developed by Toyota Motor Corporation and Hino Motors, Ltd. Magnetic markers are buried in the road at 2-meter intervals and at 50 cm intervals near intersections. The system detects magnetic markers with on-vehicle sensors to acquire vehicle location information. If there are other vehicles in the dedicated lane while the car is driving automatically, it must temporarily switch to manual operation. Currently it's automatic level 2, but in the future it aims to be level 4 with no one in the driver's seat. According to the people involved with Toyota this is just a demonstration test at the moment and we haven't had any concrete discussions about its practical application.