Date:

Location:

Project:

Jan, 2019

Sihanoukville,Combodia

Phase-2 planning and earthwork engineering for tourist resort development

Background

This resort is to be constructed on a terrain near the seashore, with elevation between 25-75m. 85% covered by trees. 

​

Phase 1 was already finished, like primitive roads, prefabricated houses. 

​

Phase 2 is for further constructions for standard roadway systems, resort villas, casinos, golf club, etc.

Requirements

Area Size: 1,419 hectares 

Service: 1:500 topographic survey

Output Demand:  DEM/DTM, contour lines,vector line map, DOM

Accuracy Expectation: 10cm vertical

Project Duration: one month

Preparations

1. 2-days site visit, to select a location for a GNSS base station, which should be almost the center of the zone to cover the area within 20km radius) and locations for take-off and landing.

2. Established 19 GCPs (ground control points), to determine flight altitude of aerial laser scanning and aerial imagery capture.

Fieldwork

Part 1: LiDAR survey - aerial data capture
Equipment: UAV-based LiDAR system, multi-rotor UAV + Mini LIDAR system SZT-R250 (measuring range 250m)

Part 2: UAV photogrammetry - orthophoto imagery data capture
Equipment: VTOL fixed-wing drone with 42MP camera

28 flights in total, 6 days to accomplish

Data Process

Accuracy verification: 1 day

DEM/DTM, contours, vector line map: 10 days

Orthophoto map: 4 days

Accuracy verification results:

    Standard deviation just 0.056 cm, less than 10 cm