Mr. Schmitt presented document TF-BTA-7-03 on behalf of the European Automobile Manufacturers’ Association ACEA. He admitted that a decrease of the bumper test area can be seen in average but noted that this does not necessarily mean also a decrease in the protection level. Also, decreases may be caused by other influences. Finally, Mr. Schmitt summarized some arguments shared in the TF-BTA discussion and suggested to start with the wording as presented in document TF-BTA-7-04 as basis for the future amendments to legislation. This proposal uses the corner gauge for the determination of the bumper corners as discussed during the last meeting.
Mr. Gehring noted that the TRL report already mentions that design changes might be expected in a way that a similar discussion could come up again in some years. Mr. Schmitt responded that, from a manufacturer’s view, the proposed wording addresses the main topics as discussed in this Task Force and that the proposal provides OEM’s as well as Type-Approval authorities worldwide with the possibility to fulfil a clear legislative language without causing functional issues.
Mr. Gehring was nevertheless again worrying about effects on vehicle design. Mr. Roth pointed out that for compliance with different bumper standards interaction with structural parts is needed. Therefore, the bumper corners always must be in front of the longitudinal beam for functional reasons. Mr. Schmitt added that he would expect consumer organization like Euro NCAP to prevent industry from doing “fancy things”. Mr. Zander wondered why, in this case, the bumper area could not be just defined up to the ends of the longitudinal beams as bumper test area.
Mr. Roth wondered whether BASt and BGS Böhme & Gehring were having a view focused too much on the situation in Europe. He explained that clear legislative language is necessary especially for countries with self certification. A test procedure that allows checking the outer contour of a vehicle provides for such certification environments. However, after some further discussion Mr. Zander disagreed that the corner gauge provides a practical solution because it does not address the issue and pointed out that BASt therefore insists on the consideration of the bumper beam for the determination of the test area.
Mr. Broertjes outlined that two options exist: Prepare one document that contains the corner gauge proposal and, within square brackets, also the proposal to consider the bumper beam. Alternatively, two different documents could be prepared with the same content as mentioned above, which may make it easier for GRSP to come to a conclusion.
It was finally agreed that different documents should be prepared, one for the corner gauge only and a second one for the corner gauge PLUS the bumper beam.
Mr. Zander then presented details from a Euro NCAP test at BASt (see document TF-BTA-7-11) where a vehicle was tested also outside the bumper corners at the end of the bumper beam. Testing was possible without any further problems and at the time of impactor peak loadings the legform showed a similar kinematic behavior when compared to the test performed to an adjacent area inside the bumper corners. Mr. Zander stated that also Euro NCAP concluded that testing of oblique surfaces did provide reliable legform results in some cases but did not in others. He added that even ACEA formerly proposed to assess the structural parts behind the bumper cover and that TRL stated in their report the potentially injurious nature of hard structures outside the current bumper test area. Mr. Zander said that BASt agrees with the general opinion that the structural injurious elements behind the bumper covers should be considered and therefore believes that the consideration of the entire bumper beam width is indispensable. The chair thanked Mr. Zander for his presentation but also noted that the issues with the legform rotation as shown by other members of the Task Force must be considered. Mr. Kinsky added that the cost benefit analysis done by TRL may at least challenge whether an extension of the test area can be justified at all. However, understanding the rationales of the Commission and seeing the wishes of the contracting parties industry supports an extension of the test area but clearly cannot support to always check two different methods of determining the test area. The chair noted that industry could bring up their arguments on this at GRSP.
Discussion then turned to the need of an offset from the bumper corners to the test area. Industry had explained that an interaction of the FlexPLI with some structure may be needed to control the behavior of the FlexPLI. Mr. Zander explained that according to BASt’s experiences no offset is necessary. Mr. Broertjes stated that 42 mm should be sufficient which represents half of the width of the main body of the tibia section as discussed in an earlier meeting. Mr. Kinsky noted that the initial contact of the FlexPLI with the vehicle surface may also occur in the knee area and that therefore the halved width of the knee element, i.e. 118 mm divided by two, should be used. Mr. Broertjes noted that also Japan had pointed out to need some structural interaction to achieve stable test results. However, the subject was not finally concluded but it was agreed that the draft amendments should initially contain 42 mm within the bumper corners.
With regard to the dimensions of the corner gauge, it was noted that this also had not yet been finally decided. The chair noted that from the latest discussion the dimension of 236 x 236 mm seems to be a good compromise and offered to put this into square brackets in the draft amendment for the time being.
Finally, it was noted that a justification may be needed for the documents. Mr. Zander stated that it also must it be proven that vehicles aimed to be affected by the new definition of the bumper test area are really affected. After some discussion it was agreed that the chair will prepare, with the help of the secretary and BASt, draft amendments for the amendment of UN Regulation 127, based on document TF-BTA-7-04. Two amendments will be prepared as discussed above, one containing the definition of the bumper corners using the corner gauge and one adding the bumper beam width as a second criterion for the test area. The secretary noted that formally TF-BTA is a sub group to the gtr 9 Phase 2 Informal Group and it was consequently agreed to also prepare respective amendments for the gtr No. 9.
The secretary pointed out that still a decision on the transitional provisions may be needed. Mr. Broertjes explained that the clear target of the European Commission is an enforcement of the requirement together with the FlexPLI and that the same conditions should apply. A final decision on this can be made in GRSP.