Sun Hill was tasked to undertake a complete survey of Westminster Bridge using the Leica Pegasus:Two mobile mapping system. This required the combination of vehicle mounted and boat mounted scans. The aim of the survey was to produce a topographical survey for the top of the bridge, extracted elevations for the bridge faces and delivery of combined point clouds for the entirety of the bridge.
Given the importance in maintaining traffic flow along one of London’s key bridges, the use of the Pegasus mobile mapping system allowed the survey to be undertaken without any road or underbridge closures and without any disruption to the local area. This methodology also reduced the risk to our surveyors and the public compared to traditional methods.
Ground control on the bridge was used to accurately align the mobile mapping scans from the boat to the vehicle mounted scans. Each bridge arch was scanned 6 times with 3 different rotations of the Pegasus system in each direction to provide a dense and complete combined point cloud.
Using this methodology Sun Hill successfully captured 3D point clouds of the entirety of Westminster Bridge. From these point clouds the requested datasets were extracted and the point clouds themselves provided a permanent as built record of the bridge. Through the use of mobile mapping this project was completed quickly, safely and with minimal disruption to road or river traffic.