2D & 3D DRONE
TYPES OF SERVICES
– 3D point cloud for model creation, geo-referenced measurements and comparisons.
– 2D orthomosaic image of large area for monitoring and inspection.
– 2D orthofacade image of building for monitoring and facade inspection.
– 3D mesh model for visualization of large features and areas.
3D mesh model of Marina Barrage using images taken with drone
As technology advances with the rapid progress of globalization in Singapore, the need to adopt safer and faster techniques in place of labour-intensive work has become increasingly important for businesses to stay competitive.
In the area of data acquisition for monitoring and inspection purposes, the use of drones has definitely changed the way how facilities management, consultants and construction project teams manage their design, maintenance and construction works. With various post-processing steps, raw images and video footage taken during the drone flights could provide users with a comprehensive view of the existing conditions and current situations on the ground with geo-referenced information right from their desk.
Application in past cases in Singapore and in the region:
– Produce geo-referenced 3D modelling of buildings and plants to revise and update existing drawing records.
– Produce 2D orthofacade imaging of large rock face for tunnel design work.
– Produce 2D orthofacade imaging of building to identify visible surface defects.
– Produce geo-referenced 2D orthomosaic to inspect required installation within a construction site.
DIFFERENT DATA ACQUISITION APPROACHES FOR VARIOUS LEVELS OF REQUIREMENTS OF COMMON IN SINGAPORE
Before the start of each project, it is important for both the data acquisition team and client to first establish a common understanding on what is required of the drone flights and how it will affect its data accuracy over the time taken, effort spent and other resources allocated. The four main types of data acquisition approaches differ in terms of how the images are geo-referenced. They may be done by:
– GPS data
– Ground Control Points
– Real-time Kinematic
– Post-processed Kinematic
Sample of a Digital Surface Model for an area size of approx. 7.5 ha
CONDUCTING 100% VISUAL INSPECTION USING DRONE FOR BUILDING FACADE INSPECTION IN SINGAPORE
Raw and non stitched-up images may not be able to provide the facade inspectors with a good overview of the facade. This is due to fact that significantly more time is needed to screen through and identify the location of every image taken during the drone flight, in order to ensure a thorough visual inspection is conducted on the facade. In contrast, an ortho-rectified facade image of a building front generated through image post-processing (like the above) allows the data acquisition team to screen through the facade with a large stitched-up image to further identify and classify the defects seen.
2D ORTHOMOSAIC IMAGE OF LARGE SITES TO MONITOR AND INSPECT THE PROGRESS OF REQUIRED SITE INSTALLATIONS
Unprocessed images and videos taken with drones may be sufficient for the project team to monitor the progress of their construction site. However, this monitoring effort may not be as effective if the data is to be shared among multiple stakeholders. Therefore, a compatible file format on a common sharing platform that is able to provide meaningful geo-referenced information will mitigate the problem. This could be achieved by producing GIS compatible images geo-referenced with the required coordinates system as specified by the client.
Geo-referenced images like this can be overlaid with multiple GIS data to provide a realistic view and comparison between design layouts and actual positions of the existing assets and installations in progress.