Smart motorways are stretches of high speed road where the traffic flow is managed remotely from a regional control centre.
Depending on the traffic circumstances, the electronic signs can be changed in order to manage speed limits and lane layout. This includes using the hard shoulder at times when traffic needs to flow quicker.
The overhead signage on smart motorways is intended to over-rule the standard signs and understood speed limits. For example, the normal 70mph speed limit on a motorway or dual carriageway may need to be reduced in order to make the area as safe as possible.
In the case of an accident or roadworks, the overhead signs would show the new speed limit and/or indicate which lanes are closed. Another scenario would be if a lorry sheds it load, or other debris was causing a hazard to road users. The annual expense involved in preventing accidents is always much less than the impact of the accidents themselves.
Without smart motorway signage, it would take hours for Highway Maintenance to arrive at the scene and place temporary notices to notify motorists of the hazard ahead. Instead, a centralised control system means the process of cordoning off a lane or issuing hazard warnings can be done in a matter of seconds.
The enforcement of new speed limits can be done using speed cameras, although the initial act of slowing down to the new rate can itself be a danger. If an accident or hazard ahead means that hundreds of drivers of different sizes need to quickly slow down, the initial incident can produce a domino effect.
One innovation which we might see on smart motorways in 10 years’ time is a road surface with integrated LED lighting. Instead of using a standard asphalt with white or yellow painted lines, the smart road would be mapped out with lighting. This could be re-configured in the event of roadworks or lane closures from a central control office.
The initial cost of implementing the system would be huge, but the amount of highway maintenance would be reduced. Imagine a road that could also be heated at the click of a button. This would save the annual resource cost of gritter lorries and further reduce the amount of accidents.The technology exists to have these roads powered by solar energy, so this is something that could be a game changer in highways across the developed world. First we had smartphones, now it’s time for smart motorways to shine.