HD 3D Laser Scanning, Drone/UAV & Inspection
- HD 3D Laser Scanning
- 3D Modelling (Rhino 3D)
- Structural Inspection Model
- SMART Image Enhancement
Sector: Engineering & Inspection
About This Project
The Iron Bridge, Exeter is a Grade II (Listed) Cast Iron Bridge (Constructed 1835) & is known throughout the world as the symbol of the Industrial Revolution. The Bridge has 6 Arches (40ft Arches), 6 Iron Ribs make up each Arch, which are cast in Sections with 2 No. Masonry Abutments at each end.
Survey Methodology & Project Delivery
Establish Control Network Framework
Primary Survey Control was established around the perimeter using Total Station (1”), GNSS & Precise Levelling. PK/Mag Survey Nails with Survey Markers were drilled/fixed into hard standing surfaces. Secondary Control was transferred by Total Station from Primary Control Stations. Black & White Laser Scanning Targets (Checkerboard Targets) were positioned at key locations along the Bridge & observed as Tertiary Control to reference 3D Laser Scanning Works.
Survey Control Network Post-Processing
Field Observations were Post-Processed through SCC Survey Software to calculate Least Squares Adjustment & Analysis (Residuals, Standard Errors, Error Ellipses) to produce final Control Network Coordinates.
Data Acquisition/Capture
Data was acquired/captured using a combination of Robotic Total Stations, GNSS, HD 3D Laser Scanning Technology, Drone/UAV & Sony Alpha a7R.
HD Inspection Imagery was captured using a combination of Drone/UAV & Sony Alpha A7R Camera.
Scan Data & 360 Image Post-Processing
3D Point Cloud Data combined with Drone/UAV & 360 Images to produce an Accurate 3D Inspection Model of the Bridge/Structure. SurveyWorx SMART Image Enhancement was used to RECOVER DETAIL IN POORLY LIT AREAS, SHADOWS, OR BRIGHTLY LIT AREAS. The result was a superior level of Image Quality.
Quality Assurance (QA/QC)
Quality Assurance procedures were completed with a Point Cloud Registration Report exported to highlight registration accuracy. Registration was a success with an average error of +/-2mm between individual Point Clouds.
The Point Cloud was Verified/Checked by taking sample Cross Sections/Slices through the Data in order to check for any discrepancies between individual Point Cloud alignments. Point Cloud Data from the Internals was also Verified/Checked against the External Data to confirm successful Registration.
Coordinate Reference System
Delivery & Output
Glossary
GNSS = Global Navigation Satellite Systems.
RTK = Real Time Kinematic.
GPS = Global Positioning System.
OSGB36 = Ordnance Survey National Grid Reference System.
ETRS89 = European Terrestrial Reference System.
WGS84 = World Geodetic System (GPS/GNSS).
ITM = Irish Transverse Mercator.
Sample Delivery/Output
Services
