The document analyzes separating direction indicators and stop lamps. It examines how drivers recognize lighting functions through visual perception and notes that irregular lamp shapes increase reaction time. The document states that “apparent surface”, currently defined only through manufacturer drawings, lacks perceptual grounding because it ignores luminance distribution and edge contrast. It recommends minimum lamp sizes and distances based on visual acuity, minimum luminance requirements, and a 3:1 luminance contrast between functions when spatially merged in one lamp.
A literature review on direction indicator visibility presents research on vehicle lighting design, visibility, and signalling. Sources include studies on overlapping and interlocking of lights, and dynamic evaluation of automobile rear lighting configurations.
The agenda includes corrections to UN R150-01, baseline documents for UN R53, R74, R86, and R48, simplification of paragraphs 6.×.4 and 6.×.5, transitional provisions, harmonisation of requirements, apparent surface considerations, and direction indicator visibility improvements. The next meetings are scheduled for June and December 2026, with a potential September 2026 session in Tokyo.
The Task Force Data Analysis completed data revision for RD-ASEP specifications, identifying errors and inconsistencies. The document lists considerations for database improvements, including updating limits to UN R51.03 phase 3, clarifying vehicle reference speed definitions, correcting reported loads exceeding 100%, selecting correct parameter tables, and addressing gear shifting detection. Additional recommendations involve determining acceptable factor x ranges, resolving minimum dynamic calculation inconsistencies, increasing vaMAX validity thresholds, and reconsidering AVAS term applicability for hybrid vehicles.
The group will receive comments on the draft UN Regulation for buses and coaches, covering definition order, operation isolation of the physical inspection system, vehicle master control switch definition, transitional provisions, type approval tests, and paragraph 5.4.4.6.2. The agenda includes feedback on a proposal made to GRSG and discussion of the September meeting location.