Thanks to one of our operators in Latin America, we have a great new method for creating a single survey with multiple individual flights. This is a valid method for any user with a 3DR flight controller who uses our FarmLens Uploader™ desktop application to geotag their photos. Keep in mind that if your photos are already automatically geotagged in flight, you can have multiple consecutive flights processed together as a single survey by simply grouping all the photos in a single zip folder and uploading directly to the website as usual.
The following method has only been verified for drones using
• a 3DR flight controller
• Mission Planner ground control software
• the FarmLens Uploader™ desktop client for image geotagging
• a camera that is NOT triggered by the flight controller
You will understand this camera requirement once you read through the following…
This process works just like a single-flight survey.
With a single flight, you have to start the telemetry log before the flight (by connecting to the drone via Mission Planner) and start the cameras taking pictures. After the flight is over, you stop the cameras and then end the telemetry log (by disconnecting in Mission Planner). This way, you end up with a single photo set that is within the time frame of a single telemetry log. This is necessary for accurate geotagging in FarmLens Uploader.
In a multi-flight survey, you are simply perpetuating a single photo set and single telemetry log over the course of multiple flights. By leaving the cameras running and never disconnecting from the drone, you are creating a single photo set that falls within the time frame of a single telemetry log, just like with a single-flight survey.
To survey an area that is too large to cover in a single flight, do the following:
1) Create the survey pattern over the entire area you wish to survey as if it will be done in a single flight.
2) Initiate the survey flight as you normally would.
3) When the drone runs low on batteries activate RTL and it will return home to land itself. Be sure to account for distance and wind when deciding when to throw RTL. Important: make a note of the last waypoint number you passed.
4) When the drone lands,
A. Do not stop the cameras; leave them running.
B. Do not disconnect the telemetry link.
5) Press the Safety button on the drone, change its batteries, and plug in the new batteries. Once you turn it back on with the new batteries, Mission Planner will automatically reconnect to it and maintain a contiguous flight log. The camera(s) must stay running the entire time.
6) In the Mission Planner > Flight Data screen, select the Actions tab (lower left quadrant of the screen). Open the pull-down box to the left of the Set Mode. Select the last waypoint you passed before throwing RTL. Then press the Set Mode button. Confirm that this waypoint shows in the “xxx > yyy” indicator in the lower right corner of the heads-up display (upper left corner of the screen). Launch the drone in Loiter mode and put it back into Auto mode when at a safe altitude.
7) The drone will pick up at that waypoint and complete the mission.
8) Repeat this procedure until the drone has finished flying the entire survey pattern.
9) Once the drone has completed the survey pattern and returned home for the final time, stop the cameras and disconnect from the drone in Mission Planner.
10) Proceed to upload the photos with FarmLens Uploader™ as you normally would. The photos will all be in one giant set and they will be paired with one continuous telemetry log from the survey flights.
Using this multi-flight survey method, you can do a single survey of an enormous area by flying non-stop.
Keep in mind, there are still a number of limitations to the area you can cover in a single survey:
• If requiring more than four individual flights, you must be able to charge your batteries as the drone flies. If using an Agribotix Enduro, you can charge two sets (four batteries) at once using the battery charger provided by Agribotix. If charging at a standard rate and if each flight utilizes the Enduro’s full range, you will always have a fresh set of batteries ready.
• Your camera’s micro SD card can run out of space. The micro SD cards provided by Agribotix have 16GB of storage. If this is insufficient for your needs, you can purchase much larger SD cards for your camera to extend your survey area limit.
• You must maintain telemetry connection to the drone the entire time it is flying. If you fly too far away and break the telemetry connection, you won’t be able to geotag any photos taken while the connection is broken.
• If doing a multi-flight survey, you may intend to let your drone return automatically once it has triggered it’s low-battery failsafe. Know the limits of your drone and ensure that it will be able to make it all the way back home once this failsafe has been triggered. You don’t want to overestimate your drone’s failsafe return range and have it crash on it’s way back.