J. Murphy uses Extended Visual Line of Sight (EVLOS) to survey large project for National Grid
Construction and engineering company J. Murphy and Sons engaged ProDroneWorx to carry out a topographical survey of a large project for National Grid using drone technology and Extended Visual Line of Sight (EVLOS).
Using drone technology allowed the 2D/3D survey grade accurate digital data to be captured much quicker and safer than traditional methods, being completed in one day as opposed to five. It also supported greater collaboration on the project by providing deeper data insights, improved H&S and data deliverables to the client while enabling the comparison of the as-build vs design.
As part of Network Rail’s (NR) programme of electrification of the Midland Mainline Railway, a new 400/25kV substation is being built on land adjacent to the railway and the existing 400kV overhead lines between Market Harborough and the village of Braybrooke. The new substation will be a compact site designed around an existing pylon which will connect the substation to the overhead line.
With Extended Visual Line of Sight (EVLOS) permission granted by the Civil Aviation Authority (CAA) in 2018, ProDroneWorx conducted the topographical survey within a range of 1.5km from the drone pilot. This special permission allowed the project to be surveyed quickly and safely. Not many companies within the UK are allowed to operate drones at these distances.
ProDroneWorx produced survey grade accurate 2D/3D digital data using drone technology on this vast site of approx. 60 acres. The scale of the project, which has a 40 metre height variance over a distance of 1.5km, was very challenging. Without the digital information captured by the drone, surveying the project would have taken Murphy’s surveyors/engineers a considerable amount of time.
“In one visit, the drone collected data that would have taken five days to survey on foot. The next planned visits will produce progression and As-Built surveys which can easily tie in with data collected from traditional total station/GPS equipment. I believe this combination of practices will become more common on sites in the future” said a Murphy’s Project Engineer.
Using the latest development in RTK/PPK drone technology, ProDroneWorx provided survey grade accurate 2D and 3D digital data outputs with global accuracies of approximately 40mm. This digital data enables Murphy to digitally manage the large project while providing deeper data insights, better collaboration on the project, improving data deliverables to its client - National Grid, while reducing costs and risks.
The following survey grade accurate digital data georeferenced to the OSGB 1936 (OSTN15) were produced for this project:
3D Point Cloud