Background
Many authorities have signal controlled locations where loops have failed, ducting has collapsed, or for very old sites, does not even exist. The situation is likely to get worse as the increasing number of Electric Vehicles, which are heavier than their petrol or diesel predecessors, is adding to the degradation of road surfaces and the loops embedded in them. Under these circumstances the traffic control systems need the detection data but can not get it, so have to operate ‘blind’ and at a lower efficiency.
For local authorities, re-instating loops incurs significant cost, delay and the disruption of deploying traffic management. The over-all cost of undertaking civils works and re-instating loops has increased significantly.
Bath and North East Somerset have a SCOOT site where the loops have failed. As this is an important link in the city’s network, it was important that a fix was to be found quickly and efficiently.
Solution
Bath and North East Somerset needed a flexible and simple way of re-instating damaged, unreliable or failed loop detection and feeders, keeping traffic optimisers, controlled junctions and crossings operating optimally. The Coeval Detector Data Communication System (DDCS) has been designed specifically to relay detector data from a roadside location to a cabinet, i.e. as an alternative to loop feeder and damaged or collapsed ducts.
The case study site required that data from two failed loops be relayed back to the controller. Based on previous experience and the two zone capabilities, BANES chose an AGD 650 detector. For the purposes of the DDCS any other suitable detector that supports the TOPAS 2505 standard connector may be used.
Coeval’s DDCS on Display
Outcome
Due to the absence of operational loops we are not able to implement a straightforward before and after or like-for-like study. A preliminary assessment of latency and continuity of data were checked, with no issues being raised. Bath & North East Somerset are and will continue to monitor and report on the site over the weeks and months to ensure that this continues to deliver the required level of service.
