Signs of the future

摘要

Intelligent road signs started to make a modest appearance on UK roads in the late 1970s and have been evolving and proliferating ever since. Intelligent signs are now deployed across the network and broadly seek to manage traffic, influence road user behaviour, provide public information and facilitate enforcement. Early signs were often electro mechanical (EM) and typically consisted of a series of rotating prisms allowing a number of different fixed sign faces to be displayed. The advent of light emitting diodes (LEDs) of sufficient brightness and colour rendition opened up opportunities for more sophisticated signs incorporating text and pictograms replicating signs in the Traffic Signs Regulations and General Directions (TSRGD). As we will see however the EM sign still has a place in the market and can have advantages over purely electronic signs in some circumstances.