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I wouldn't say that I'm "into electronics", but I can say that I am impressed with the maturation of lidar surveying.
By firing your lasers out of the right equipment, you can create an astonishingly detailed survey with a tiny fraction of the time and effort that a traditional survey would require. In my job as a civil engineer, I have worked with lidar "point clouds", generated by putting the equipment on a truck and driving down the side of a road at low speed, that have one observation in every four inches (ten centimeters), extending over entire miles (kilometers) of six-lane freeway, including the trees and slopes in the roadside. And there are point clouds at resolution of around 1 dot per 1 meter (3 feet) covering most of my entire state—thousands of square miles (square kilometers)—that were obtained by sticking lidar equipment on an airplane.
Of course, traditional surveying is not quite dead. A UAV can't check the elevation of a pipe inside an inlet, or clear away debris to see where the true edge of pavement is, or use a metal detector and a shovel to uncover a monument that was installed three generations ago. And processing dozens of 300-megabyte 3D point clouds into 2D topographic features takes a powerful computer and a competent drafter many hours of work. But the technology still is very impressive, and a lot more accurate than redrawing topographic features from bad scans of as-built construction plans that were surveyed two generations ago—and it's accessible to amateurs. There are zillions of YouTubers touting aerial (drone-mounted) lidar surveying as a small business to get into. A lidar drone is in the low five figures to purchase.
I've been very loosely intrigued by the advent of phone-based lidar systems like the one that's apparently now included in modern iPhones. Do you (or anyone else) have experience using these lower-end lidar systems? How big is the gap between that system and the next highest price tier of specialized lidar equipment for a casual user who is not surveying professionally?
We have a small (2-3 acre) rural property that's very non-uniform in shape, elevation, orientation of structures, etc ... is it within the realm of possibility that I could use one of the lower-end iPhone systems, paired with e.g. a smaller DJI flight-programmable quad drone, and wind up with a scan that, if not inch-accurate, would be broadly useful for planning or visualizing new constructions or modifications to existing ones? (I have the 3D/CAD experience to get the rest of the way once I have a point cloud.)
I have the impression that even the low-end lidar might be more dimensionally accurate than doing a traditional, camera-based photogrammetry session with, say, the same iPhone + drone setup. Is this correct?
A reasonably-accurate scan of our property and the ability to do it for others would be helpful and fascinating, but not five-figures helpful or fascinating. Maybe four figures if the first figure is a 1 and if it's also equipment I can do aerial photography with. Depending on how usable the scans are at what scales, I could see myself getting into scanning for all types of projects of smaller scope once I've got the equipment.
For something as large as a scan of the property, though, would I be better off trying to find someone locally who I could hire to do it once with very good equipment?
I have not personally used any phone-based systems (or point clouds from such systems). However, based on some YouTube videos that I've watched (1 2), it's my understanding that phone-based lidar systems work only at short range, and therefore are not suitable for scanning large swaths of terrain.*
For your purposes, photogrammetry may be more convenient. The OpenDroneMap software (1 2 3) can digest aerial photos and spit out a point cloud. (Disclaimer: I do not have a UAV and have not used this software.)
*Phone-based systems can be useful, though. I recall attending one presentation at work (several years ago) where our resident tech guru gushed over his test of a phone-based system (I don't remember whether it was lidar or photogrammetry) in surveying the corner of an intersection, which would be very convenient for designing ADA-compliant curb ramps.
No new information to add here, just thanking you for the helpful response. I think I'm going to dive a little deeper into the world of photogrammetry.
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