1. Putting Some Reality into the Glare and Visibility Debate
GRE IWG “Simplification of the UN Lighting and Light-Signalling Regulations” (SLR)
Document SLR-32-10
Date:
Submitted by GTB
Putting Some Reality into the Glare and Visibility Debate
Note: Part of this document (specifically pages 2 to 11 inclusive) was introduced at the SLR 31st session to offer an introduction to the discussion concerning agenda Item 14 on the subject of Headlamp levelling.
As the document presented to the 31st session did not offer any new information it was not submitted for publication.
However, to respond to the complaints of lack of transparency by the representative of Poland, GTB is now submitting this version that includes a proposal on how the IWG-SLR could decide to proceed.
This document should be considered in combination with the document SLR-31-11e submitted by GTB.

2. GRE 73rd Session, April 2015, Agenda item 6b.
OICA/GTB did not have the opportunity to present GRE/2015/5 and the detailed supporting justification in GRE but Poland was given the opportunity to present its informal documents GRE and GRE (responding to GRE/2015/5).
This meant that Poland was objecting to the OICA / GTB proposal before GRE experts were given the opportunity to understand the depth of the detailed study and calculations that had been carried out by GTB using the method developed by CIE TC4-45 and published as CIE S 021.

3. These two diagrams are misleading due to their different scaling

4. 0.4% (0.212 deg.) upward inclination
The diagrams of GRE/2019/03 and GRE superimposed
It is important to appreciate the actual values being debated.
The values highlighted in Yellow are angles in degrees of arc.
i.e. the gap between the initial aim upper and lower limits of the blue box is 0.9 degrees!
This is already a major challenge for the vehicle manufacturers.
0.4% (0.212 deg.) upward inclination

5. HISTORY of the GRE debate
Scientifically produced proposal based upon CIE procedure
GRE has not considered a serious study by GTB
Immediate compromises introduced to satisfy personal theories to provide governments with responses to complaints from the public concerning glare.
More adjustments because of attempts by GRE to satisfy the objections of Poland

6. The results of calculations based upon real lamp photometry using the CIE S 021 procedure.
These red lines are justified on scientifically based grounds.
Poland is the only CP to have challenged these results.
GRE73-06
APRIL 2015

7. The results of calculations based upon real lamp photometry using the CIE S 021 procedure.
Data points removed for clarity
GRE73-06
APRIL 2015

8. The results of calculations based upon real lamp photometry using the CIE S 021 procedure.
The curved boundaries derived from the calculations were simplified into a parallelogram as shown here
GRE73-06
APRIL 2015

9. GRE73-06
APRIL 2015
The results of calculations based upon real lamp photometry using the CIE S 021 procedure.
The curved boundaries derived from the calculations were simplified into a parallelogram as shown here

10. GRE73-06
APRIL 2015
With GRE Superimposed
The results of calculations based upon real lamp photometry using the CIE S 021 procedure.
The RED parallelogram has been modified to become the green dashed shape by arbitrary negotiation without any scientific justification.

11. HISTORY of the GRE debate
The arguments submitted by Poland continue without a scientifically justified basis and the conclusions of GTB, based upon scientific evidence continue to be ignored.
At the SLR-24 session GTB presented its views on the approach to glare and visibility issues in document SLR
GTB explained why the current balance between glare and visibility cannot be significantly changed in the context of current (non-adaptive) headlamp technologies.
This GTB work is based upon scientific, peer reviewed, methods and is validated by evaluation of the performance of a range of headlamp designs and technologies.
Again, Poland tries to invalidate this work with its usual unjustified comments and continues to block progress in GRE.

12. Proposal for a way forward
The debate on Glare and Visibility issues (associated with the debate relating to mandatory installation of static automatic levelling) pre-dates After 9 years of debate at GRE, GRE-IWG-VGL and GRE-IWG-SLR, no progress has been made and the same arguments from Poland remain.
GTB is preparing proposals to improve the Glare / Visibility balance as part of the GRE-SLR Stage 2 programme.
GTB has submitted the proposal for a way forward in SLR This proposes to:
complete Stage 2 simplification that will offer improvements to improve the Glare / Visibility balance for existing headlamp technologies
launch a new GRE Informal Group to develop a technology neutral vehicle based performance requirements that will be applicable to all existing technologies and expected innovations. These technical requirements SHALL be compatible with the terms of the 1958 and 1998 agreements.
Is it now appropriate for GRE to seek a conclusion by means of a democratic vote of the CPs, based upon the principles proposed in SLR-31-11?