Currently (March 2017), Arc Surveying & Mapping, Inc. is conducting experimental topographic construction surveys utilizing an IMap – M4 Quad Copter equipped with a V-Map 200 kHz Dual Frequency GPS receiver and a Sony A6000 24 mp camera utilizing a Sony 16mm f/2.8 Pancake lens capable of 11 mm GSD @ a 50-meter flying height producing centimeter accuracy and highly detailed georeferenced photogrammetry. The results of this test are outstanding.
On the aerial photograph, the construction equipment is grading and tilling for the next lift of embankment. The construction limits are shown in yellow, a silt barrier is visible to the right. Design grade is shown dashed red and elevations derived from the aerial data are shown in green. The cross-section at Station 23+00 illustrates the results of the Arc Surveying & Mapping, Inc. aerial survey compared to the Arc Surveying & Mapping, Inc. conventional survey performed a day prior. Note that the surveys overlay perfectly with the drone data (dashed red) providing detailed continuous data across the section. There are several advantages to UAV surveys performed by a Professional Surveyor and Certified UAV pilot.
- Obtain a topographic construction survey and georeferenced imaging simultaneously
- 100 % of the construction area is surveyed instead of being cross-sectioned at 50 or 100 ft. intervals
- Job site conditions are visible, such as construction material beyond the design template
- Easily observe that construction is built to lines and grades
- Survey can be obtained in work areas without safety concerns
- AUV surveys over conventional surveys are excellent QA/QC checks
- More accurate quantities are available in either end area or mass volume formats
- Reduces conventional survey manpower (Although data processing manpower is time consuming)
Initially, Arc Surveying & Mapping, Inc. is finding that the benefits outweigh the concerns on certain projects when comparing the use of conventional crews versus UAVs and look forward to expanding this innovative technology.