In Europe, the practical application of C-ITS (Cooperative Intelligent Transport Systems) will start in 2019 and in the United States, a part of C-ITS service is expected to be legislated during the fiscal year 2018. In Japan, the ETC2.0 and DSSS (Driving Safety Support Systems), which are partly similar to C-ITS, have already been put to practical use. Most notably, the number of cars using ETC2.0 is now close to 3 million (as of the end of January 2018).
In Europe, it is worth noting that the step for practical application will be taken after the formulation of regulations concerning the protection of personal information during the collection of probe data*1. Meanwhile, in Japan, the protection of personal information during the collection of probe data has not really become a subject of debate. The reason is that ETC2.0 has one effective feature. While the details can be found in the written specifications*2 and other related documents, hear I will give an outline.
In the case of ETC2.0, probe data is not recorded in the on-board unit for approximately 500 m from the point of departure and all stored data from approximately 500 m before reaching the destination is erased. Further, by issuing an ID using random numbers, ID-attached data from up to approximately 80 km upstream of the roadside unit can be transmitted to this unit. This feature enables the tracking of vehicle behavior while erasing personal information.
"The Levels of Driving Automation" proposed by SAE (Society of Automotive Engineers) International was revised in 2016 and the concept of ODD (Operational Design Domain) was introduced. In short, this is to define the driving environmental constraints for the self-driving. In order to determine the constraints, various elements should be combined such as weather condition, road category, road condition, and related regulations. Further discussion is expected in the future before the details are finalized. The first country to respond to this concept seems to be the Netherlands, which introduced the world's first minicomputer system to control lane-by-lane speed limits. Having had a strong interest in C-ITS, while reducing investments for hard infrastructure, the Netherlands is trying to implement C-ITS as a tool for their road traffic control system.
Based on the idea of the Netherlands, I illustrated the relationship between the ETC2.0 probe data system and ODD. The point is that by making use of a feature like the ETC2.0 probe data system, it is possible to keep track of a vehicle’s trajectory within the ODD range without infringing personal information protection laws. Consequently, a self-driving system with ETC2.0 makes it possible to record the trajectory of a self-driving car and confirm the vehicle behavior in the traffic flow within ODD. This is very important for road traffic control purposes and also to form a public consensus on self-driving systems.
Unfortunately, the advantage of the ETC2.0 probe data system is not recognized internationally due to a lack of publicity from Japan. This technology can be used independently of the frequency and protocol of communication equipment. By combining it with the concept of ODD, the concept of public probe data for road traffic control will become clearer. Design parameters like 500m and 80km and which media to use can be decided according to the circumstances of the corresponding country. Therefore, this technology is basically usable anywhere in the world and can be considered as a prior technology for C-ITS. Moreover, the ETC2.0 probe data system is capable of contributing to the establishment of a road traffic control infrastructure for the self-driving age. I believe it should be widely demonstrated to the world.
*1 General Data Protection Regulation (GDPR) May 2018
*2 Standard specification for DSRC section of ITS On-Board Unit (TT-6002B) by JEITA