Portsmouth is currently trialling XCam smart video sensor technology for vehicle presence detection at traffic signal junctions; the first city in the UK to undertake such trials of this product.

XCam works by detecting both standing and moving traffic at the junctions and interfacing with the on-street traffic signal controller. Priority can be adjusted to prevent undue delays for general traffic and public transport.

It is hoped that this new video detection technology will enable economic and environmental improvement within Portsmouth through significant improvements to traffic flows, reducing congestion and delays to public transport, and therefore improve air quality within the vicinity of the trial sites.

The XCam has the ability to detect stationary traffic whilst being unobtrusive and easy to maintain and should prove a reliable alternative to traditionally used detector loops that are cut into the road surface. Whilst the most reliable detection currently available, detection loops are expensive to install and are often damaged by road works and require disruptive road/lane closures to be able to repair them.

How does it work?

The XCam detects the vehicle as it moves towards a junction. As the vehicle enters defined areas or "zones" within the camera's field of view, the camera's processor detects a change in the "zone". An output is sent to the traffic signal controller (the computerised "brain" housed in a nearby metal cabinet controlling the junction's lights) that indicates a vehicle is requesting a green signal for its approach.

Two trial sites are installed in Portsmouth:

Commercial Road/Marketway Roundabout

XCam was installed at this site to provide reliable and accurate bus detection at the traffic signals. When detected, the bus gets a priority ‘green light’ which enables the buses to exit the designated ‘bus and taxi zone’ much quicker thereby reducing delays to public transport.

Winston Churchill Avenue/Portsmouth University

XCam is being trialled at this site to overcome issues with existing sensors, which do not recognise when a queue has formed, and the green call is not processed. The XCam offers the opportunity to accurately detect queuing vehicles, ensuring that the traffic signals work more effectively in clearing potential traffic congestion especially during the rush hour period.

Peter Eccleson, Managing Director of Smart Video & Sensing Ltd, said: “This innovative technology will drive efficient, economic and environmental improvement within Portsmouth by improving traffic flows, reducing congestion and hence pollution. We strongly believe that this cost effective solution will in many instances replace the expensive loops in the carriageway thus enhancing detection reliability.”

Pam Turton Portsmouth City Council's Assistant Director for Transport, Environment and Business Support said: "As a densely populated city we are always looking for ways to reduce congestion and improve traffic flow, particularly for buses to reduce journey times and encourage the uptake of public transport. We are delighted to be trialling the XCam technology and will be really interested to see what difference it makes at the two trial sites."