A recent project in Ireland demonstrates how road asset performance demarcation surveys – and their evaluation – can be made more efficient
In 2016, Northern Road Markings (NRM),based in Northern Ireland, successfully completed a mobile retroreflectivity survey of the primary and secondary road infrastructure in Ireland, having won a Transport Infrastructure Ireland (TII) tender. As well as measuring the retroreflectivity, this tender also introduced inspection of road studs and barrier reflectors.
NRM selected a RetroTek vehicle-mounted full-lane multiline reflectometer from Reflective Measurement Systems (RMS) to complete the contract. “The flexibility of RetroTek has allowed NRM to meet and exceed the stringent requirements set by TII,” says Mark Kelly, CEO of NRM.“The easy setup and ability to measure line retroreflectivity, studs and barrier reflectors on both sides of a lane, and then illustrate these results on the MultiView mapping and video interactive platform, made the RetroTek-M a competitive choice.”
TII required the multiple surveys to be cataloged for easy selection and filtering, to save time loading data and finding surveys. The MultiView interactive map and video saved considerable time when analyzing results. The software facilitates changing the results thresholds to allow TII to predict where markings may fail.
Users can navigate the inspection results, visualize the inspected data and review the acquired image data for each road. Results, maps and videos are GPS synchronized. MultiView’s cloud hosting capability means the survey data can be stored in a safe and secure location and viewed remotely.
The RetroTek-M retroreflectometer attaches to the front of a vehicle. Its cameras can sense the full lane width, which is illuminated by projected LED light in a geometry that conforms to CEN EN 1436 and ASTM E1710.
Machine vision software is used to locate road assets in the field-of-view. This data is combined with GPS for accurate positioning. Precision driving close to road markings and markers (studs) is not necessary.
Repeatability and reproducibility of results form a key pillar of RetroTek technology. Independent certification by StrAus-Zert, test certificate No 0913-2015-02, demonstrated that RetroTek-M achieves similar, if not better, performance than leading handheld retroreflectometers.
The RetroTek technology, along with the MultiView mapping and video analysis software, allows TII to manage its maintenance funding and ensure that road maintenance contracts are conforming to the contract retroreflectivity (nightvisibility) specifications.
The data results, including mapping and video information, are stored securely for analysis and shared over the internet with other maintenance engineers and contractors. As the surveys were completed in the spring/summer, this enabled TII to plan maintenance schedules early, at the beginning of the road marking season – giving plenty of time to complete the task.
RetroTek measures across full lane width. While traveling at 120km/h (74mph) on a seven hour shift, it is capable of measuring 840km (521 miles) of road lanes. It simultaneously collects information on up to 1,680km (1,034 miles) of lines and markers, plus 840km (521 miles) of center-lane markings and barrier reflectors. A total of 5,040km (3,131 miles) of road assets compared to 1,680km (1,043 miles) from traditional dynamic retroreflectometers.
The equipment is safe to use for the driver/ operator and other road users, as only normal driving behavior is required and the system has sufficient road clearance to prevent accidental damage. It is easy to calibrate, so surveys canget underway in minutes. The setup also conformsto CEN EN 1436, EN 1463 and ASTM E 1710. PDF maps can be produced for each road asset type, helping TII to plan financial requirements for road marking maintenance.
TII has carried out several years of surveys using RMS and RetroTek technology. This has enabled them to efficiently direct funding. Cyclic measurement has delivered measurable year on year improvements in performance. They are happy with the performance of RMS in delivering the necessary surveys and haveawarded commissions to NRM in 2016 and 2017.
ADAS and autonomy
ADAS functions are now in use in many new vehicles. The EU and the USA are mandating that all new vehicles be equipped with AEB and forward collision warning systems by 2020. These technologies rely on visible road markings, day and night. “RetroTek is an accurate, efficient and safe technology to operate at all traffic speeds,” says James Mahon, CTO at Reflective Measurement Systems. “It greatly assists road stakeholders to certify road marking condition and which road networks are suitable for the safe operation of vehicles with ADAS and for autonomous vehicles as they come on stream.”
This article was first published in the Intertraffic World Annual Showcase 2018 and can be viewed here.