This report summarises the off-road research trials on display parameters for the proposed Motorway Signal Mark 4 (MS4), carried out by TRL on behalf of the Highways Agency. Trials were conducted initially on the original prototype version of the sign, with a second set of trials conducted later on an improved prototype. The trials investigated both the legibility and comprehension of text messages and of pictograms. Dynamic trials established the comprehension of text messages and pictograms seen by drivers travelling at motorway speeds. Static trials investigated the legibility of text messages and pictograms. The results of these trials were used to establish the size of the MS4 display panel and text messages proposed for the on-road trial. The programme of work started in June 2000 and was completed in March 2003. (Author/publisher)
Samenvatting