INNOVATION September-October 2015

Photogrammetry software has the ability to project contours (1 m) onto photographs.

onboard flight controller. The UAV executes the route under pilot supervision but without pilot input. Semi-autonomous flights are useful for surveys and mapping, and they significantly reduce the workload at the post-flight processing stage. Post-flight Processing Once the UAV is safely returned to the ground, the collected data must be converted into the desired product. This may be as simple as selecting the best photograph, or it may involve building a three- dimensional terrain model. Photogrammetry software recognizes the same features on a series of photographs and develops a surface model from the geometric relations. Software packages include Photomodeler Scanner, AgiSoft PhotoScan, Pix4D, VisualSFM, and more. Unfortunately, the software does not do well with vegetation or water, as both can move between photographs and can have highly complex surfaces that do not facilitate matching. However, the software excels on terrain features, such as mine sites, gravel bars, bedrock surfaces, and landslides. Enduring ground control points are recommended for geospatial referencing and monitoring work that uses repeat surveys. Applications While UAVs may not provide the same first-person experience as flying in a manned aircraft does, they are better suited for collecting high-quality images. In one example, several helicopter flights produced only a few quality photographs, but within one hour, a UAV had collected many high-quality photographs that allowed the construction of a three-dimensional model and orthophoto mosaic. Over three years, the BC Government has used UAVs to assess, among other things: • Inappropriate off-road vehicle use; • Streamside land-use impacts; • Rockfall hazards; • Road maintenance and associated landslide issues; • Fish obstructions; • Landslide characterization and modeling; • Fluvial geomorphic research; • Snow and plant ecology research, and; • Mining disturbance surveys. Using UAVs is saving costs for the provincial government, and many of these operations would not

have been possible had conventional manned aircraft been required. In addition, UAVs allow dangerously unstable sites to be assessed safely. Only the UAV is exposed to the hazard, while operators and other personnel remain at safe distances. This reduction in risk and liability serves to further lower organizations’ costs. Conclusion Drones are coming, and they’re coming in droves. Over the next few years, the use of UAVs is expected to increase dramatically across an ever-expanding range of applica- tions. Applying the right equipment and skills is essential to producing quality products. Professional and licensed engineers and geoscientists are obligated to comply with airspace and associated regulations. Now, as a personal professional challenge: How could you do your work better by using a UAV? v Dr. Matt Sakals, P.Geo., is a research geomorphologist with the BC Ministry of Forests, Lands and Natural Resource Operations, based in Smithers, BC. He has been using rotary-wing UAVs in his work since 2013, and is interested in the application of UAVs throughout the natural resources sector. This article complements Sakals’s presentation, Using Unmanned Aircraft: From Regulations to Results , at the APEGBC 2015 Annual Conference.

OQM Organizational Quality Management Program

The following organizations have recently received OQM Certification. To find out more, visit apeg.bc.ca/oqm. AEDON Consulting Inc. DWB Consulting Services Ltd. Fraser Valley Engineering Ltd. Gygax Engineering Associates Ltd. Integral Engineering Inc. LMDG Building Code Consultants Ltd. Temec Engineering Group Ltd. BC Ministry of Transportation & Infrastructure

19

S E P T E M B E R /OC TO B E R 2 015

i n n o v a t i o n