Pit & Quarry, August 2017

DRONES MAPPING Surveying with a drone Consider that both photogrammetry and LiDAR offer viable advantages from the sky by JEREMIAH K ARPOWICZ urveying and mapping professionals have been using both photogrammetry and LiDAR for measurement and survey purposes for a long time now As such the question about which is more effective has come up in various ways In fact the contention that photogrammetry would make laser scanning obsolete is one that was making waves not too long ago But for anyone who takes the time to look at both technologies its immediately evident that better and obsolete arent words that really belong in this conversation Its true that drones have made it easier than ever to create 3 D models and there are undoubtedly people who are convinced a cheap camera and drone will be all you need to gather the appropriate data for a given project On the f lip side there are people whose only experience has been with LiDAR compelling them to ignore or disparage photogrammetry Anyone making either claim is only looking at a specific application of the other technology or his or her motivations are being driven by something besides what is going to be best for a given user There are simple and in depth ways to look at the differences between the two technologies and UAVs unmanned aerial vehicles have given the conversation a whole new dimension Professionals who work with these tools on a daily basis understand their strengths and limitations better than anyone and they can provide critical insights around how to best leverage the technology DRones As A gAme chAngeR Drones have brought photogrammetry to the forefront in an incredibly powerful way enabling more developed conversations Rather than convince people a 3 D model can be constructed via photos a number of people have moved on to ask about the logistics behind the process Much of this is because people recognize what can be done when the right cameras and sensors are attached to a drone but LiDAR has been impacted as well UAV LiDAR systems open up a new market which we call micro mapping says Grayson Omans CEO of Phoenix Aerial Systems Conventional aerial LiDAR service providers typically turn down projects that are less than 5 sq km due to high mobilization costs but now with UAV LiDAR systems service providers can quickly mobilize and complete this size job in less than a day The perspective a drone provides is far removed from traditional capture methodologies as users can control the drone to fly at a certain elevation to get a certain percent overlap as well as plenty of other angles and views The volume of data they gather allows users to get what is often the perfect image set that will meet the majority of their needs which is far different from controlling a human whos walking around in a space and trying to make sure they get sufficient imagery Drones have opened up the industry to people of all types of skill levels and that has created problems in terms of expectations However its also encouraged certain organizations to take on capture data themselves and the results of such undertakings are often mixed The challenge now is that people can go to a big box store to buy a drone and hook it up to a service that provides f light automation and data capture says David Boardman CEO of URC Ventures So we end up with people who are asking why this is so hard when there are low cost solutions that are available which they can then go do themselves Those are the sorts of people that are running into known issues and known problems just because we have so many new people in the space who are not GIS professionals or surveyors Experiencing pains is an issue users and organizations will go through but S4 PIT QUARRY August 2017 pitandquarry com Photos courtesy of DroneView technologies s