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DeveloperPermalink Reply by Michael Oborne on October 12, 2012 at 11:59pm

yes it is possible

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Permalink Reply by Anthony Schnabel on October 13, 2012 at 6:07am

How is this done?

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Permalink Reply by Greg Fletcher on October 13, 2012 at 6:46am

Click on the "write waypoints" button in the lower right corner of the flight planner screen.

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Permalink Reply by keeyen pang on October 13, 2012 at 7:16am

We all load the way point file in manual mode before we fly. Isn't it. So it doesn't matter if the plane is in the air on sit on the ground.

It may be more interesting to find out if we can upload a new way point file after it had finish the mission upload earlier. 

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Permalink Reply by Anthony Schnabel on October 13, 2012 at 8:06pm

So if we send a new flight plan to the apm while the plane is flying will this overwrite the current flight plan?

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Permalink Reply by James masterman on October 13, 2012 at 8:31pm

Yes, whatever waypoints are in the flight planner screen will be written to the plane mid flight, replacing whatever was in the plane previously. If the plane is currently heading for waypoint 5 of 10 and you write a completely new set of 10 points, then it will head for whatever the new waypoint 5 is and go from there. I'm not sure what happens if you have less waypoints than before, but I imagine it will just RTL.

A word of warning - depending on telemetry signal strength, I have had problems where only some of the waypoints are uploaded and you get an error before all of them are up. This is usually handled gracefully by the plane (ie. it doesn't crash), but you can have trouble updating long lists of waypoints (in my case 20). Sometimes you need to hit write a few times to make it work.

It's usually better to do it on the ground to be sure they all upload.

 

Cheers

James

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DeveloperPermalink Reply by Andrew Tridgell on October 17, 2012 at 8:05pm

yes, it is possible, although you have to do it carefully.

The mission planner currently sends a "wipe mission" command first, then uploads the new mission. That can take several seconds, during which time the plane has no mission. That can lead to nasty errors (the most common result is it ends up doing an RTL).

The mavlink protocol supports incremental mission updates while flying, but as yet MP doesn't do this. mavproxy can do it, and we used that capability during our OBC mission (in order to change the mission based on the results of our image recognition). If you want to do this with MP then you'll need to talk to MichaelO about adding support for incremental mission uploads. If you are using mavproxy then you can do it now.

Cheers, Tridge

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DeveloperPermalink Reply by Andrew Tridgell on October 17, 2012 at 8:11pm

a bit more details ...

To do an incremental mission change in flight you should use the MISSION_WRITE_PARTIAL_LIST MAVLink command. That takes a range of wp numbers to change and the APM then asks the GCS for those changed waypoints. That command is currently supported by ArduPlane, but not by ArduCopter.

This allows you to update a contiguous set of waypoints within the mission by sending just the changed waypoints. This is what mavproxy does when you drag a waypoint on the map (although mavproxy also adjusts the altitude according to the terrain model to keep the waypoint at the same altitude above ground level).

Adding new waypoints instead of adjusting existing ones is a bit trickier as you need to be careful the plane doesn't start using a waypoint that isn't uploaded yet, especially if you are using jumps. Right now mavproxy doesn't have a command line interface for doing that, although it can be done in a mavproxy module in python.

Cheers, Tridge

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Permalink Reply by Matt on February 26, 2013 at 10:41pm

How does the apm determine when it can or can't upload and overwrite a new flight plan?
We tried uploading a new flight plan whils in stabilize mode and auto mode and it wouldn't take.
The only way we could do it was to land and reboot, then upload a new plan.
Cheers

Matt

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Permalink Reply by Brenden on February 27, 2013 at 6:50am

I can't answer your technical question specifically but I can tell you that in my experience data rate setings, amount of data you are writing, and distance have an impact. I update parameters and WP missions almost every flight now and I noticed that at lower data rates and at greater distances it fails more often. That being said at times I've written 40+ WP at nearly half a mile out without a problem. If I'm writing a bunch of waypoints and it fails multiple times at a distances I simply switch to rtl and try as it gets closer or while circling overhead. It almost always succeeds. I know this is an experiential answer and not a technical one but I hope it's helpful.

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Permalink Reply by Matt on February 27, 2013 at 12:59pm

Thanks Brendan,
I had alved my data rate and it was afew hundred meters away when I was trying, so I'll persist and try again.

Cheers

Matt

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Permalink Reply by Brenden on October 18, 2012 at 12:03pm

I have not yet done what I am about to say but I am planning to test running two separate missions while plane is still in air by doing the following:

On ground via 3dr telem upload/write first mission to APM using MP. Launch and run first mission. At completion of first mission switch to loiter mode using switch on tx. Upload second mission. Switch back to autopilot mode again using switch on tx. I think this will initiate the second mission and then RTL after completion.

Anyone agree or disagree from experience?

Thanks

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