Vehicles are increasingly equipped with systems that take over (elements of) the driving task. Eventually, this is expected to result in fully self-driving vehicles. The human role will shift from driver to supervisor, and ultimately to passenger. These systems are assumed to reduce the risk of human error and consequently to increase safety. At the same time, human factors will still influence the systems. After all, in the role of supervisor, human intervention is still necessary when the system requires it or in the case of system failure. Furthermore, it is still unclear how other road users will react to new systems. To stimulate innovations concerning self-driving vehicles, the Netherlands facilitates the testing of self-driving vehicles on public roads. As road safety is the main prerequisite, the Ministry of Infrastructure and the Environment asked SWOV Institute for Road Safety Research for advice on how to carry out field trials with self-driving vehicles in the safest possible way. The Ministry of Infrastructure and the Environment has drawn up the Procedure for testing self-driving vehicles on public roads in the Netherlands. This procedure is used as a guideline when filing a request for an exemption to allow field trials on public roads. The procedure (Figure 1) consists of three closely interrelated components: vehicle, road and human (behaviour). RDW, the Dutch Vehicle Authority, coordinates the permission for a field trial. RDW is also responsible for the vehicle component. The road authorities or CROW Taskforce Dutch Roads are responsible for the road component, and SWOV is responsible for the (human) behaviour component. The test procedure has been designed in such a way that improvements can be made based on the experience gained in each trial. The test procedure is therefore continuously being developed. To structure the safety advice on human behaviour, SWOV has developed a ‘Risk matrix’, describing potential risks of a field trial with (partially) self-driving vehicles. The Risk matrix is based on literature and expert knowledge.1 It identifies potential risks involved in field trials and how they can be — or already have been — mitigated. The Risk matrix is presented on the following pages. Its first dimension maps a number of risks in the following categories: 1. Risks due to the interaction with the system/vehicle; 2. Risks due to the interaction with other road users; 3. Risks due to the location and moment of the trial; the route and the place on the road are important considerations; 4. General risks due to project management. The risks are (co-)determined by the level of automation of the system and the role (still) played by the driver. The second dimension of the matrix thus distinguishes three levels of automation: a. Partial automation — driver is active At this level, the system temporarily takes over (elements of) the driving task — either steering or accelerating/braking. The driver performs all other dynamic driving tasks, such as monitoring the driving environment and the system. The driver functions as a fall back and needs to detect when action is necessary. b. Conditional automation — driver is important The driving task is performed by the system. The driver performs the other dynamic driving tasks: monitoring the driving environment and acting as a fall back if this is indicated by the system. The driver now performs the role of supervisor. c. Full automation — driver is not important The system takes over all driving tasks, monitors the driving environment as well as the system itself. The system detects if it is necessary to take action. The driver plays no active role in this vehicle and has now become a passenger. In some cases a remote operator will monitor the vehicle and the environment.
Samenvatting