Rijkswaterstaat (RWS), the national infrastructure agency of the Netherlands, have a requirement to improve the safety for road users on bridges and at other critical points. They identified that stopped vehicles in moderate traffic was the major cause of the problem.
In order to find a solution, they first assessed the capability of all the equipment available from around the world that could detect stopped vehicles. They then invited selected manufacturers to submit their equipment for evaluation against 37 sequential tests on a long track that was hired for the duration. Up to 20 vehicles were used to simulate a wide variety of incidents that may occur on bridges. (See our report “Demonstrating Radar Performance on Test Track”)
RWS then invited those manufacturers with the best performing equipment to submit proposals for a system to be installed on a bridge on the A50 motorway over the River Rhine. A 9 month trial period has been designated to establish how a state of the art stopped vehicle detection system could be used to provide 24/7 traffic monitoring, alerting patrols to incidents as they occur, reducing collisions and improving the safety of, in particular, ‘all lane running‘ sections of motorway.
End client: Rijkswaterstaat
Country: Netherlands
Ogier Electronics equipment: SVR-500 radar
We are delighted that RWS consider the performance of our equipment to be particularly high with a detection probability of better than 97% and a low false alarm rate; markedly better that most of the other equipment. RWS also found our commercial proposal to be the most attractive. As a result, we won the competition and were selected to supply and manage the system for the duration of the trial on the A50.
Project Leader, Ogier Electronics
The challenge
The A50 bridge deck is high above the waterline to allow large boats to pass underneath. There are six traffic lanes in total (three in each direction), plus segregated cycle ways and footpaths on either side. However, there are no hard shoulders or stopping areas anywhere on the bridge, hence the need for rapid stopped vehicle detection. Another feature is that unlike regular roads, this bridge moves slightly and has many joints to allow expansion and contraction.
The solution
Our winning bid specified three SVR-500 radars along with ancillary support equipment pre-configured to form a turnkey solution. All of the equipment was installed during overnight road closures. The SVR-500 radars were mounted high on the existing bridge gantries to help minimise obscuration due to tall vehicles. The rack-mount support equipment was installed in the existing roadside cabinets.
We also specified the installation of high-performance pan/tilt/zoom (PTZ) cameras near to the radars on the same gantries. These PTZ cameras are under radar control to automatically point at the detected events, allowing footage to be available for post-incident analysis. In addition, a continuous 24-hour video stream is saved to provide a ground-truth to compare against the radar detections. A similar video verification scheme had already been used successfully during our UK on-road trials so we knew the technique and methodology were appropriate. All video is purposely recorded in low quality to avoid any GDPR infringements.
During the commissioning phase the system has already correctly, and rapidly, detected a variety of accidents, collisions and breakdowns on the bridge.
RWS and ourselves will be analysing the data over the next 9 months. This will be used to optimise the detection and false alarm rates in this environment wherever practical. However, its main purpose is to provide RWS with enough real time experience to create meaningful, specifications for stopped vehicle detection systems that are technically feasible, affordable and above all will lead to fewer accidents and save lives.
