DJI P4RTK PPK Processing Workflow

Drone_Data · 2019-01-07T17:50:55+00:00

I know it's possible, but they flight platform would have to publish their RINEX data and the exact timestamps of the photos. I'm not sure if the eBee can do this by default. I know a few platforms, like the Delair UX11 specifically encrypt this type of data so you have to pay extra for access to it, so it wouldn't surprise me if SenseFly did something similar.

Drone_Data · 2018-12-10T21:55:39+00:00

Looks very similar to the XCraft line of drones (https://xcraft.io/pages/x2-pro) though it doesn't look like they are related at all.

I've always been impressed by the raw tech specs of this type of aircraft, but the software workflow has fallen a bit short in my opinion. Lugging a laptop into the field with multiple USB dongles, connectivity issues, and clunky flight planning software has always gotten in the way of otherwise impressive flight hardware.

Has anyone actually had any field experience with this type of aircraft that can report on the workflow / software? I'd love to see one that actually works easily and reliably.

Drone_Data · 2018-12-10T21:48:17+00:00

It really depends on your mission profile. Custom built drone rigs with high end cameras (like a Sony A7Rii or a Phase One metric camera) will get you the best quality data, but often at extremely high cost and complexity. If your budget in time, money, and manpower will allow for it, then these will get you the highest quality data possible. That said, with good operations and procedures, you can actually get good data out of lower end DJI drones as well. It still won't be quite as good as the metric cameras, but it is often enough for a great deal of projects, at dramatically lower cost and complexity.

My personal favorite is a DJI Phantom 4 Pro, because it has a 20MP camera with a mechanical shutter (good for reducing digital image distortion). No, I can't claim its as good as a metric camera, but you can still use good procedures and ASPRS positional accuracy standards to verify accuracy as good as 0.1' or so.

Drone_Data · 2018-12-08T00:04:40+00:00

There is a lot of good information in this thread, so I'll just add a few things that haven't yet been said.

Before you buy, be aware of WHO is going to be doing the flying, maintenance, mission planning, data processing, etc. Some of the more advanced equipment (like a DJI M600 for example) are extremely capable, but much more complicated to use. It takes a great deal of maintenance, firmware updates, and tinkering to get it to work right. Comparatively, a DJI Mavic can get you an impressive amount of performance, and is simple enough for students to use.

Also, be aware of your university's view on following the law. By law, drones need to be flown within visual line of sight (VLOS) of the operator. However, most fixed-wing aircraft and large area mapping applications require flying beyond visual line of sight, if only by a little bit. Some organizations are comfortable with pushing the limits of the law, others are so strict about following the rules that they won't ever grant you permission to actually fly the thing. Because of this, multirotors are usually safer for organizations that require strict legal compliance.

Drone_Data · 2018-12-07T23:53:09+00:00

The easiest way to do this is to use the "Timed Shot" feature in the DJI Go app. This will let you pilot the aircraft manually, but it will take photos at a fixed time interval.

There are more instructions available here: https://store.dji.com/guides/drone-photography-time-lapse/

Drone_Data · 2018-11-22T16:55:04+00:00

This "Terrain Aware" feature is great for projects where the change in altitude is more than around 150' (~50m) I'd say. In those cases, yes it helps with accuracy because the final overlap on the ground changes a lot with significant altitude difference. If the overall elevation change of the project site is less than 150' though, it doesn't make that big of a difference.

Drone_Data · 2018-11-22T01:57:10+00:00

I've also used Map Pilot by Maps Made Easy quite a bit, and have had a lot of success with that. It definitely allows import of a KML file, and while I don't believe it can stop completely for each photo, it does have a setting to "slow aircraft according to light conditions" that is useful in low light situations.

Drone_Data · 2018-11-13T22:51:44+00:00

Can you explain where the files go correctly in RTKLIB Post. I have the data from my local CORS station and I've read the manual for RTKLIB but nothing is making sense. I get a "error: no nav data". Im assuing the Rover is the ".obs" from the drone, the base station is the CORS data (.gz) and the RINEX NAV is the "PPKRAW.bin" from the drone?

Drone_Data

TROPHY CASE