Larry Scott, post: 448702, member: 8766 wrote: I asked: what did you use for control? That's when it got impressive. He had 6 targets, laser printed paper, circular bar code targets. The software scanned the images and automatically identified the 3D control, auto correlated and bundle adjustment without operator assistance. (On a good day, but he had the process down pat.)
This is fine for small areas - a drone flying a house at 100'. If you are flying large areas at a greater height the size of barcode target needed becomes unwieldy.and you need a lot of flat ground to set them on. You also need to be sure that the targets will stay in place, so you can't use road markings, etc. It's then probably easier to manually identify the targets on the photos. Once you've picked one in Photoscan it puts up all the relevant photos so you can check each quite quickly.
We flew 150 ha. of quarry and landfill last Tuesday, 26 ground targets at 0.4m square and 6 road markings.12 hours total site work. This was an extended site where we had previously done ground survey, so the untouched areas gave a good ground check - typically +/- 50mm (during the setting of the ground targets we took additional GPS points in areas of vegetation to check the accuracy of the filtering and to provide "area" corrections for the undergrowth). When the site was first surveyed it took about 10 days on the ground..
Boundaries - fine for general topo, but not suitable for exact delineation. Even when fences go under tree cover you can generally get quite a good line from little glimpses through the canopy. As with all methods, you need to be selective. If you are setting ground control then the GPS can pick up additional information in the areas where you know the vegetation will obscure important points.
imaudigger, post: 448699, member: 7286 wrote: I am looking at possibly contracting out a drone survey instead of a traditional survey due to accessibility/safety issues.
I think it is definitely a technology that will be broadly used by most surveyors. Will the surveys be cheaper for the clients?...Probably not.
Hopefully not. We do real work, we should make real money, we should charge real fees.
Larry Scott, post: 448725, member: 8766 wrote: You could take a picture of your girlfriend with a 2500 mm telephoto lens at a hundred yards. Compare that a photo of your girlfriend with 100 mm lens 4 feet away.
And I would still know it was my girlfriend and what dress she is wearing .... which is all I might need to know.
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chris mills, post: 448750, member: 6244 wrote: This is fine for small areas - a drone flying a house at 100'. If you are flying large areas at a greater height the size of barcode target needed becomes unwieldy.and you need a lot of flat ground to set them on. You also need to be sure that the targets will stay in place, so you can't use road markings, etc. It's then probably easier to manually identify the targets on the photos. Once you've picked one in Photoscan it puts up all the relevant photos so you can check each quite quickly.
We flew 150 ha. of quarry and landfill last Tuesday, 26 ground targets at 0.4m square and 6 road markings.12 hours total site work. This was an extended site where we had previously done ground survey, so the untouched areas gave a good ground check - typically +/- 50mm (during the setting of the ground targets we took additional GPS points in areas of vegetation to check the accuracy of the filtering and to provide "area" corrections for the undergrowth). When the site was first surveyed it took about 10 days on the ground..
Boundaries - fine for general topo, but not suitable for exact delineation. Even when fences go under tree cover you can generally get quite a good line from little glimpses through the canopy. As with all methods, you need to be selective. If you are setting ground control then the GPS can pick up additional information in the areas where you know the vegetation will obscure important points.
The barcode targets seemed workout pretty well with 11x17. The software locating the targets automatically, even if not 100%, I thought was a big deal. It was little effort.
And you've seen good results. It comes down to being able to do it in-house with modest cost. It's not for every job. Like you pointed out, a dynamic industrial/construction site, like quarries could be done on a monthly basis. Not like the good old days. Insurance adjusters are using them, and they're more than a pretty picture.
In 1988 we bought 2 Trimble 4000SL, 5 channel L1, receivers: $55k ea. And the work window was only 4-5 hrs long. Between computers, training, etc, that was $150K 1988 dollars. That was the next big thing.
So a drone investment doesn't seem so scary.
BushAxe, post: 448754, member: 11897 wrote: And I would still know it was my girlfriend and what dress she is wearing .... which is all I might need to know.
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That may very well be all you need to know. Right tool for the job and all. I don't see satellites won't out-do drones for small areas which are in acres not sq mi.
Drones only seem to work in certain places. Kind of costly down under...
That would put a damper on your day.
After recently reading about an extremely experienced UAV operator receiving a prison sentence related to a crash I'm not overly interested...
Jim in AZ, post: 448835, member: 249 wrote: After recently reading about an extremely experienced UAV operator receiving a prison sentence related to a crash I'm not overly interested...
[SARCASM]Better put away your bicycle, too[/SARCASM]
http://www.sfgate.com/crime/article/Bicyclist-sentenced-for-fatal-S-F-crash-4736312.php
My only concern is the pilots license you need to get and registering with the FAA. I am sure it can be done... but another factor.
Overview of FAA requirements. My friend that it's pretty easy.
Blog page in drone mapping:
https://www.dronezon.com/learn-about-drones-quadcopters/introduction-to-uav-photogrammetry-and-lidar-mapping-basics/
Scotland, post: 448837, member: 559 wrote: My only concern is the pilots license you need to get and registering with the FAA. I am sure it can be done... but another factor.
Not a very big deal. Easily done in less than a few weeks of evening study, even if you don't fly; less if you do. Registering a UAS is on line and takes minutes.
Jim in AZ, post: 448835, member: 249 wrote: After recently reading about an extremely experienced UAV operator receiving a prison sentence related to a crash I'm not overly interested...
He probably did what Larry's friend did ("let it take off and go inside the house and come out 10 minutes later"). FAA regulations do require maintaining visual contact with the UAS at all times. How that works in the real world is another discussion, but, just sayin'.
rfc, post: 448851, member: 8882 wrote: He probably did what Larry's friend did ("let it take off and go inside the house and come out 10 minutes later"). FAA regulations do require maintaining visual contact with the UAS at all times. How that works in the real world is another discussion, but, just sayin'.
The demo that I saw was probably not the most adherent demo. But it wasn't commercial either.
Okay he didn't really go back in the house except for a minute to send the start command. The point was that the craft flew a flight plan with flight lines, predetermined photo centers, predetermined altitude, and the photos were taken by coordinate not ground speed or time interval. And that flight plan was generated by menu and parameters, not cad drawn. And not joystick.
Commercial application has rules. Sites have unexpected things like power lines to beware of.
It's a market share decision. Cost benefit risk analysis. Regardless it'll become more common.
FrozenNorth, post: 448836, member: 10219 wrote: [SARCASM]Better put away your bicycle, too[/SARCASM]
http://www.sfgate.com/crime/article/Bicyclist-sentenced-for-fatal-S-F-crash-4736312.php
I think that's a great idea! They certainly shouldn't be allowed on City streets. My vehicle was struck several years ago by a bicyclist traveling about 30 mph. Although she claimed she was uninjured I had to endure watching her face smash into my windshield. She hopped up and exclaimed "I don't have any brakes." She was a minor and had no insurance, so I sued her parents in small claims court for the repair cost ($1,200), only to be told by the judge that parents weren't responsible for damages caused by a minor unless their actions were malicious! While I was picking up my repaired vehicle the body shop told me that they had another vehicle they were repairing, a car hit by a bicycle in a parking lot. The bill for that one was $3,000. Several months later my boss was hit broadside by a bicyclist who ran a stop sign. His helmeted head entered my boss's truck and struck him in the head, splitting his forehead open and deploying the side airbags. repair bill? $10,000 - cyclist had no insurance (none do). Cyclist spent 16 days in the hospital. Sorry for the hijack, but bicyclist are incredibly dangerous things! BTW - there's no sarcasm here.
As a cyclist (even though I'm currently shaped like a potato), the mentality I have when riding is that every driver is going to try and knock you off. Some even actively pursue you to have a crack. And that extends to the general public as well. But back to the OP, certainly around here, I'd say putting up a drone would attract people to try and knock it out.
Jim in AZ, post: 448835, member: 249 wrote: After recently reading about an extremely experienced UAV operator receiving a prison sentence related to a crash I'm not overly interested...
I have read about a few jail terms for folks being dufus's but no hard time. Would love to hear the rest of the story...
Here's a cheap gimbal:
[MEDIA=youtube]LEGZ7hGaMNI[/MEDIA]
I'll chime in with my experience using drones with field surveys.
At the last company I worked for, one of our party chiefs was a UAV licensed pilot. We had a drone with a conventional camera (not LiDAR) that we used to fly sites up to about 40 acres. Workflow went something like this:
1. Crew arrived on site.
2. Drone pilot would identify the physical limits of the survey and paint targets on the ground in appropriate locations (red X's).
3. Meanwhile, the other person would set up the GPS base and start taking shots on the painted X's.
4. Once the targets were shot by GPS, the drone would go up and fly the site. The pilot kept his eyes on the drone, the other started searching for boundary.
5. Flight done, the boundary search would be finished and local control (PK nails, spikes, whatever) would be set.
6. Conventional survey methods would be used to take shots on "hard surfaces" and other necessary features. The focus would be on things not readily seen in the drone imagery.
7. Once done, the crew packed up and brought in the data.
8. In the office, I would download their points file and imagery.
9. We used Pix4D, and I would "tag" the flight targets in the appropriate photos and assign the surveyed point for that target.
10. Set the software running and we'd get a point cloud and ortho-rectified photo.
11. Boundary was resolved as we always had.
12. Topography was drawn based upon a combination of field shots and imagery data.
So it wasn't much of a change from previous work flow. The key difference, and this is what sold us on using drones, was that the end result was a topography drawing with a beautiful, high resolution orthophoto as an underlay to the drawing. When clients saw this, they absolutely loved it. As is said, a picture paints a thousand words, and this was no exception. When you can talk with a client about their site and point at a picture and say something like, "Over here, next to that existing sidewalk, there's a steep drop off. And you can see the low point here based on how the grass is greener." Or whatever the talking point is. Clients can see the site and relate in their mind what is there with what you're trying to explain. Not all of them have that understanding with traditional "line only" topography. And if my boundary information is shown with the orthophoto underlay, they rave about that as well. It is great.
My current company is on the brink of adopting drone technology. I'm studying for my drone license and once I get that done, we will start putting drone work into our deliverables.
skwyd, post: 449312, member: 6874 wrote: We had a drone with a conventional camera (not LiDAR) that we used to fly sites up to about 40 acres. Workflow went something like this:
You'd think for all the taxes you pay in California you'd get better service ;). I can download 1:1200 orthos from county GIS websites for the low, low price of...free.
James Fleming, post: 449324, member: 136 wrote: You'd think for all the taxes you pay in California you'd get better service ;). I can download 1:1200 orthos from county GIS websites for the low, low price of...free.
Yeah, but I don't think a lot of the counties here have orthos of the land. Plus, nothing beats having an image of the day of the survey. On one of my sites, we flew it the day after the underground was marked up. You could read the paint marks in the ortho. In color.
One thing we also would add to our products was 360 onsite images. The crew had a 360 camera mounted on top of the rod, so they could take a shot on the site and call it "Pic4" (or whatever). Then they'd take a panoramic image at that point. We could put a link in the CAD file that would show up in the PDF such that clicking on it would allow viewing of an onsite 360 image of the site at that point that the client could pan around.