Alas, another RTH question.

[Sprocket]

Can I cancel RTH, fly around for another few minutes, and then hit RTH again? Will it resume RTH? I didn't see anything in the manual that addresses this question. Thanks in advance.

 

[sar104]

Yes. Why wouldn't it?

 

[Sprocket]

Sometimes things happen for a reason that I don't realize right off. That's why I'm glad someone invented the art of asking questions when one is not sure.
The RTH data might have been dropped from memory for all I know.

 

[msinger]

Will it resume RTH?

There is no way to resume an RTH. However, you can initiate and cancel it as many times as you'd like during a flight.

 

[sar104]

Sometimes things happen for a reason that I don't realize right off. That's why I'm glad someone invented the art of asking questions when one is not sure.
The RTH data might have been dropped from memory for all I know.

Of course - but I was wondering what led you even to consider that. RTH simply returns the aircraft to the home point. Were you worrying that cancelling RTH might erase the recorded home point?

 

[Sprocket]

Of course - but I was wondering what led you even to consider that. RTH simply returns the aircraft to the home point. Were you worrying that cancelling RTH might erase the recorded home point?

Yes it was. I have always had strange thoughts pop into my head about things. For some reason I just wondered what would happen.
Usually I have a stupid fit or two on a daily basis. I guess that was one of them for today.

 

[Rockowe]

Sometimes things happen for a reason that I don't realize right off. That's why I'm glad someone invented the art of asking questions when one is not sure.
The RTH data might have been dropped from memory for all I know.

Interestingly - the QUESTION is Excellent !

I was testing the RTH accuracy of the ZOOM - ...
THe Two times that I cancelled the RTH - and then Resumed it - were followed by the two times that the Drone BADLY calculated its Home Point accurately and Landed up to 4 Meteres away and Dangerously - almost landing in a SHrub.

So cancelling DOES SOMETIMES mean a Loss of original Accuracy - as Sprocket implied

 

[Rockowe]

There is no way to resume an RTH. However, you can initiate and cancel it as many times as you'd like during a flight.

Please see my last REPLY and Quote

 

[Nfhill]

Interestingly - the QUESTION is Excellent !

I was testing the RTH accuracy of the ZOOM - ...
THe Two times that I cancelled the RTH - and then Resumed it - were followed by the two times that the Drone BADLY calculated its Home Point accurately and Landed up to 4 Meteres away and Dangerously - almost landing in a SHrub.

So cancelling DOES SOMETIMES mean a Loss of original Accuracy - as Sprocket implied

Your conclusion is not supported by the facts. All you've proven is the accuracy of the Mavic Zoom's GPS is normal. A 4m error is normal.

If your MAVIC returns to its takeoff point within inches, it's either luck or because the accuracy was improved by some means other than GPS, such as the downward facing cameras.

Nick

 

[msinger]

THe Two times that I cancelled the RTH - and then Resumed it

Since there is no way to resume a previous RTH attempt, you were starting fresh each time you initiated RTH again.

Keep in mind that different things can happen when the drone is too close to the home point when RTH is initiated. For example, it could auto land 4 meters away from the home point if it's too close to the home point when initiated.

 

[sar104]

Interestingly - the QUESTION is Excellent !

I was testing the RTH accuracy of the ZOOM - ...
THe Two times that I cancelled the RTH - and then Resumed it - were followed by the two times that the Drone BADLY calculated its Home Point accurately and Landed up to 4 Meteres away and Dangerously - almost landing in a SHrub.

So cancelling DOES SOMETIMES mean a Loss of original Accuracy - as Sprocket implied

That's an interesting observation, but inconclusive. The M2Z has precision landing, provided that the conditions are correct. 4 m is not unreasonable without precision landing. So the question is - on those two occasions did it have the necessary conditions for precision landing and, if so, was precision landing somehow cancelled when RTH was cancelled the first time. That would almost certainly be a bug in the firmware.

How many RTH tests did you do at that location, and did you pay attention to satisfying the RTH takeoff requirements? Did the GO app tell you each time, on RTH, that precision landing was engaged?

 

[Sprocket]

It occurred to me that if I was BLOS and panic set in then I could hit RTH to bring it back to VLOS. I might have a lot of battery charge left. In order to not waste the charge I could resume flying. Then when I decided to land I could hit RTH again and all would be well.
I wouldn't expect or want to resume the exact track home that I had cancelled. I could be a long ways from the last point the drone was when I hit RTH. I wouldn't want it to fly to the point it was when I first initiated RTH and then RTH. Hence my original question.

 

[DanMan32]

It's a good question, especially considering the thought patterns behind it.

Many of us use RTH only get our bearings back and continue flying or land manually.

Each initiation of RTH is handled independently with the current home point at the time of initiation. Home point by default will be where you launched, but you can change it mid-flight to the then current AC position or the RC position (assuming your device has GPS).
Note that RTH rules get complex when performed near the home point, including landing right where the AC is if too close to home point.

You can also orient yourself by the radar and map. Map will show a line between AC and home point. Just turn AC until it lines up with the line.
Or line up AC nose with radar center.

 

[Meta4]

It occurred to me that if I was BLOS and panic set in then I could hit RTH to bring it back to VLOS. I might have a lot of battery charge left. In order to not waste the charge I could resume flying. Then when I decided to land I could hit RTH again and all would be well.
I wouldn't expect or want to resume the exact track home that I had cancelled. I could be a long ways from the last point the drone was when I hit RTH. I wouldn't want it to fly to the point it was when I first initiated RTH and then RTH. Hence my original question.

Your drone stores the location of the home point at the start of the flight - just so it knows where to return to if necessary.
That stored point stays in memory until the drone is powered off.
It does not change (unless you change it).

 

[TR Ganey]

Your drone stores the location of the home point at the start of the flight - just so it knows where to return to if necessary.

That stored point stays in memory until the drone is powered off.
It does not change (unless you change it).
.

I have a question. Many people that have had fly away's have made the comment that they assumed that the drone had maybe tried to RTH to the last location they flew from, maybe the day before etc. If the home point is erased when the AC is powered off then there should be no way for that to happen. What is actually the most likely scenario to happen when you take off and fly away prior to acquiring a good GPS home point and then hit RTH?

P.S. Please don't answer with "A fly away"!

 

[Meta4]

I have a question. Many people that have had fly away's have made the comment that they assumed that the drone had maybe tried to RTH to the last location they flew from, maybe the day before etc. If the home point is erased when the AC is powered off then there should be no way for that to happen. What is actually the most likely scenario to happen when you take off and fly away prior to acquiring a good GPS home point and then hit RTH?

P.S. Please don't answer with "A fly away"!

First, there's no such thing as a "flyaway".
If someone tells you they had one, that just means they lost their drone and don't know why.

The stored home point evaporates when you turn the drone off.
It's impossible for it to fly back to an old home point.

Your drone will store a homepoint when it gets a GPS location fix.
If you are impatient and launch without GPS, your drone will still record a homepoint when it gets GPS reception.
In most situations that should be close to where you launch, unless the sky view is blocked by terrain or cover.

 

[Sprocket]

I wonder about how RTH will work when companies start using drones for deliveries. Will RTH be stored permanently? I would think they would launch from a permanent pad. Surely they won't have to wait for GPS lock before starting their route.

I can't imagine the companies will have someone stand out in the heat or cold for the launch and return cycle.

 

[DanMan32]

They will wait, or their automated launch system will wait, for GPS lock if it is expected to have a stable flight.
Remember, a stable flight requires a GPS lock, barring VPS which requires low altitude. This is regardless of wanting a home point for GPS.

If you launch before lock and it takes 10 seconds to acquire lock, that's 10 seconds of atti flight that is difficult to fly, particularly in heavy and highly variable winds. This is where drones get lost or crash "unpredictably".

There was one time where Go 3 had a bug that placed the RC location on the map based on the mobile GPS 2.5 miles WNW from actual location. Normally this wasn't a problem unless the home point was reset to supposed RC location, or possibly distance limits. That was the only time I know of a possible legit fly away. Even then it could be avoided if you were aware of the problem: don't reset home point, don't use limits.