t 0141 255 0840   e info@coeval.uk.com

Alerting drivers to adjust their speed through dynamic signage


Alerting drivers to adjust their speed through dynamic signage 1

Following a series of accidents on a particular section of the A701, an 18-mile route from the M74 junction to the A75 junction, the 2017 Annual Road Safety Report suggested the road should be the focus of further investigation from which Scotland TranServ conducted an accident review over the previous five years.

Their review concluded that speeding and tailgating were contributory factors for most accidents along this route, particularly along the section north of Locharbriggs which was subject to the national speed limit.

In 73% of accidents, it was found vehicles were travelling above the appropriate speed threshold for the relevant vehicle class. On average, 89% of HGVs travelled above their 40mph threshold; 57% of medium-sized vehicles travelled over their 50mph limit whilst 25% of cars and motorcycles exceeded the 60mph limit.

Regarding the tailgating issue, cars and motorcycles were found to be the worst offenders with 26% travelling within two seconds of the vehicle in front compared with 17% of medium sized vehicles and 10% of HGVs.

Scotland TranServ looked to the market to find a resolution to both the issues through a single road safety initiative. Coeval worked with main contractor, Clearview Intelligence Limited, to deliver this route safety scheme.


Alerting drivers to adjust their speed through dynamic signage 2

Using an intelligent detection system to manage intelligent signage, in this case Coeval’s VAS (Vehicle Activated Signs), motorists who are tailgating or driving above the appropriate speed threshold receive a warning that is specific to their driving behaviour via the dynamic signs. Clearview’s Count and Classify system detects the gap, speed and classification of passing vehicles and transmits the information to the solar-powered VAS which prioritises the message accordingly.

For those tailgating, the VAS will show a “too close, leave 2 second gap” message whilst speeding vehicles will be presented with a “slow down” message and a reminder of the appropriate speed limit for their vehicle class. In incidents where a vehicle is both speeding and tailgating, the latter message will take precedence.


The flexibility and ability of the supply chain partners, working closely with the client, enabled the effective implementation of this bespoke solution and the reduction in accidents and speeding across the 7 locations has proven the effectiveness of the project. The change in the number of drivers traveling over the speed limit has reduced between 6 and 18 percent over the various vehicle types and the overall number of accidents along the route has also reduced significantly.

Informing and advising road users of their driving behaviours in such a dynamic and specific way is far more effective than the use static signs; drivers are alerted to the ‘error of their ways’ instantly and can adjust their speed and distance. The predicted reduction in accidents will see a 106 percent return rate on investment within the first 12 months, based on Transport Scotland’s system of valuing the cost of an accident.


Download case study

What our clients say

Connect Plus Services M25 Dartford Crossing

‘Even a short closure of the tunnel causes great congestion in the area, and if an over height vehicle were to cause that level of damage, the tunnel could be closed for hours, if not days, which would bring the whole of the South East of England to a standstill.

When the Coeval over height vehicle detectors were first installed, we were talking about 10’s of vehicles a day that we were stopping; we are now down to low single figures, 4 or 5 vehicles a day we need to extract for being over height, so it’s a great improvement in efficiency through the crossing.’

Platinum Electrical Ltd

‘Having used Coeval for the first time, we found them to be friendly and really helpful in ensuring we received the correct item we required. We were happy with the extremely quick response times and professional service they offer. We would definitely recommend their services to others.’

Gloucestershire Airport

‘Thank you for your prompt and efficient service regarding our request for training on the 21st of August. You guys have been incredibly helpful over this.’

City of Edinburgh Council

‘Coeval won the tender for the replacement overheight vehicle detector systems. The work was completed within programme and budget. We are now satisfied that the new systems will help protect the bridges for several years to come.’

Swindon Borough Council

‘A sound, honest and efficient service provided by Coeval. Would be very happy for Coeval to manufacture and supply more of Swindon’s signs.’