Proof-of-Concept and Demo at Abu Dhabi – DJI Phantom4 RTK

DJI Phantom4 RTK Drone delivering 1cm GSD accuracy in Construction Project in Abu Dhabi Urban City Development

Prepared by

Sanju Mathew, Sales Manager, Aeromotus Dubai (DJI Enterprise Drone Solution)

Customer

Saif Bin Darwish, Abu Dhabi, United Arab Emirates

Purpose of the POC / Demo

Saif Bin Darwish using DJI’s Phantom4 RTK Drone aiming at achieving 1cm GSD and to measure the level of enhanced productivity & efficiency they can achieve from DJI Phantom4 RTK in the topographic Survey in Zayed City Project in Abu Dhabi.

Summary

Aeromotus conducted a Drone-based Topographic Survey with Saif Bin Darwish at Abu Dhabi at one of their live construction projects, i.e., Zayed City in Abu Dhabi. The purpose of this POC was for the Saif Bin Darwish to achieve 1cm GSD accuracy from DJI’s Phantom4 RTK and to compare the productivity, efficiency they have achieved using DJI Phantom4 RTK drones over conventional survey and ground topographic methodologies. Outputs generated from the POC were OrthoMaps, Point Cloud, 3D Model using DJI Terra.

Summary / Findings from POC

Drone/ Camera Model	Phantom 4 RTK
Area Covered	24.7 Ha
Total Flight Time	90 minutes
No of Images Captured	1675
Total Size of Raw Images	13.8 GB
Processing Time – Ortho + DSM	78 minutes
Processing Time – Point Cloud + 3D Model	319 minutes

Survey Location

The location of the Survey Area is shown on Google Earth below. The KML of the Area of Interest was created using Google Earth Imagery. The total area is 24.7 Hectares.

HSE

As this site is a live construction site, the POC team were provided with a safety briefing for the survey personnel. All survey operations were held away from people and over the space permitted by the GCAA and SBD and in favorable weather conditions. All HSE related measures were fully implemented during the entire survey.

Drones for Survey & Measurement

Methodology

1. Pre – Survey

The mission plans were created using DJI’s GS RTK App on DJI Smart Controller.
The flight altitude was set to 36m above ground.
The side overlap was set to 65% and front overlap was set to 75%.
The flight speed was set to 3.5m/s.
Camera angle was set to -90 degrees.
The images were captured with GSD of 0.99cm/pixel.

2. Realtime Georeferencing at Site

Base Station (D-RTK2) was setup at the following coordinates:
Easting: 257326.241m
Northing: 2696114.658m
Elevation: 4.871m

Drone IMU and Compass were calibrated before the operation
The first flight took off at 10:00 am

3. Data Processing

DJI Terra was used to process the images.

Summary

Camera Model	Phantom 4 RTK
Area Covered	24.7 Ha
Total Flight Time	90 minutes
No of Images Captured	1675
Total Size of Raw Images	13.8 GB
Processing Time – Ortho + DSM	78 minutes
Processing Time – Point Cloud + 3D Model	319 minutes
Processing Resolution 2D and 3D Reconstruction	High
Data Output formats	Point Cloud in LAS, 3D Model in OBJ, PLY, OSGB Orthomosaic in GeoTIFF, DSM in GeoTIFF