The experts held a debate about the interpretation of the 2-step approach suggested by the Chair at the previous session of the informal group.

As the task of informal group is to propose an informal document to the GRRF-74th session, the experts wondered whether the suggestion by the Chair for a 2-step approach addresses the process of work of the informal group for the establishment of new provisions for light vehicles, or whether it addresses the implementation of these provisions into the AEBS regulation.

J questioned the way to increase the stringency of the requirements, knowing that the Industry has no experience. The expert pointed out that the OICA/CLEPA proposed values are already difficult to achieve, and that it will be even more difficult to reach increased values.

OICA clarified that the Industry proposal is already a step in the unknown. OICA could only offer, in the frame of a 2-step approach, a date for re-negotiate the performance criteria. More stringent requirements, would be impossible to predict at this moment.

CLEPA supported this OICA position, and pointed out that the discussions of the today’s meeting will probably show how difficult it is to reach the OICA/CLEPA proposal itself. The expert from CLEPA proposed to review the concept of a 2-step approach at the end of the day.

NL was surprised at the last meeting by the suggestion by the Chair, and understood the Chair’s suggestion as defining now the values for both steps and the necessary delay perhaps now or at a later stage, according to the wish of the Contracting Parties (EU). NL however was in favour of a 1-step approach, but was flexible on this item.

F preferred to adopt both steps at the same time, accepting the OICA/CLEPA proposal for the 1st step, depending on the date to be decided for the re-negotiation of the performance requirements (2nd step).

Germany found it difficult enough to achieve the performance requirements proposed by CLEPA/OICA, such that a potential 2nd step would have to be clarified at a date to be defined.

J found better to define early both steps (support to NL), but recognized it would not be easy.

Conclusion: minutes adopted with no change.

Germany presented the document AEBS/LDWS-18-02. The expert from Germany explained that Germany thought about asking more severe requirements, but then aligned the proposal on the OICA/CLEPA proposal. The expert summarized the justifications and stressed that the LPTS (Last Point To Steer) is usually at the same time as the LPTB (Last Point To Brake). Japan questioned the compatibility with the Vienna Convention, which would necessitate to request [1.4] latest time to warn before the automated emergency braking phase would start. The expert from D clarified that their proposal does not forbid warning earlier. The warning should be at the LPTS because up to that time it is still be possible for the driver to avoid the obstacle by steering. J was keen that there is some time between the start of the Emergency Braking phase and the warning.

CLEPA clarified that the Vienna Convention only requests the driver to be able to override the system. OICA clarified that the wording specifies “not later than”, permitting the system to warn before AEBS is taking the control.

NL was also in favour of a warning time before the automatic emergency braking system takes the control of the vehicle. The expert recalled that D was initially keen for a 2 second delay for the HCV. In addition, the N2 > 8T with pneumatic Braking System must already fulfil the warning time of row 1. The expert from the NL in addition recalled that OICA in p 16 of its presentation AEBS/LDWS-17-02-Rev.1 request 2s.

The Chair recalled one of the main principles in the adopted AEBS regulation, as specified in paragraph 5.5.1. that the timing of the warning signals shall be such that they provide the possibility for the driver to react to the risk of collision and take control of the situation and shall also avoid nuisance for the driver by too early or too frequent warnings. This principle requires both aspects to be taken into account.

OICA clarified that Industry gained experience in the meantime and could now justify the 1s TTC.

The Chair wondered whether using this 1s for warning the driver could be considered to find a common understanding on the warning timing issue.