Hubsan H501A, WiFi based but smart (in very early construction) - Page 22 - RC Groups
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Nov 14, 2017, 03:17 PM
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Quote:
Originally Posted by BrBr
3. On loss of signal drone does RTH to "nowhere" (default position is likely 0.0, 0.0 what is some 570km south off coast of Ghana, Africa)

I dare not to try this.
Anyone on a ship in the vicinity?
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Nov 15, 2017, 07:33 PM
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Quote:
Originally Posted by jonkjon
Seems like a pretty simple software fix if this is the case.
As I said, drone should not attempt RTH without having acquired home position.
Honestly, I would be surprised if this is not already done so.
I mean, this is such an obvious issue which even a beginner programmer should notice (and fix).

Quote:
Originally Posted by Hullken
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Lol! If only the battery would last so long!
Nov 15, 2017, 08:09 PM
Registered User
Quote:
Originally Posted by bluesman58
I launched as always after compass calibrate. Had no control from that point. Tried to land manually and return to home, No response. Have searched last coordinates for 3 weeks now from ground and with another quad's video. Was recording with phone app, included last 3 pics showing satellites and speed, height, etc.
That is strange.
Looking at the screenshots, the drone seems to have been descending: 26.1m@74m -> 20m@93m -> 17.6m@99m
That is a fairly constant descent rate (6.1m/19m= 0.32, 2.4m/6m=0.4).
If you recognize the ground features in the FPV and deduce the direction, you should be able to calculate the spot where it hit the ground (or trees).
The drone seems to be heading in the same direction on all 3 screenshots.
But ... hey! Speed is 16.8m/s!?!?
How did you get it to fly that fast in GPS mode?! Was there any wind? Like 60 km/h (37 mph) wind?

By the way, what is that odd looking light blue circle with white spot on the map?
It suspiciously looks like waypoints ...
Did you try to fly waypoints perhaps?
That and high wind could explain "loss of control" ...

Anyway, you should give that recording to Anne. She might explain what was going on.
Nov 15, 2017, 08:23 PM
Registered User
Or GPS was scrambled do that would explain miscalculated speed. Anyway nice explanation. Especially like the part without sarcasm and patronizing.
Nov 15, 2017, 08:32 PM
Registered User
@bluesman58
The direction the drone was pointing (based on the arrow on the map) is consistent with the 0.0, 0.0 coordinates.

Novi81 has a point. Sorry for sarcasm.
Nov 15, 2017, 08:47 PM
Registered User
Looking at the screenshots again.
The FPV looks consistent with the high speed.
The video recording timer shows only 1 second difference in all 3 shots. The road from the first shot is gone in the second one and the time delta is 1s (likely less than that).
That shows that GPS was likely fine.

bluesman58 said he searched for it at the last recorded coordinates, so the coordinates were likely not far off from the ground features (the road) else he would have noticed that (I suppose).
bluesman58?
Nov 16, 2017, 01:19 PM
Registered User
Quote:
Originally Posted by BrBr
@bluesman58
The direction the drone was pointing (based on the arrow on the map) is consistent with the 0.0, 0.0 coordinates.

Novi81 has a point. Sorry for sarcasm.
Man that is nice work. And I really mean it. Seems that you found reason for bunch of flyaways. I'm eager to hear what Hubsan think about this
Nov 16, 2017, 02:09 PM
Registered User
Am I the only one thinking that Hubsan might have an office in Ghana and that's where they're getting all those refurbs from?

Better wear my tinfoil hat the next time I go flying.
Nov 16, 2017, 08:42 PM
Registered User
Quote:
Originally Posted by Novi81
Man that is nice work. And I really mean it. Seems that you found reason for bunch of flyaways. I'm eager to hear what Hubsan think about this
Thanks, Novi!
I can't take credit for 0,0 RTH flyaways as someone else posted about that some time ago, I think here on RCGroups.
I just expanded on it.

Anyway, I don't think Hubsan will (or should, for that matter) reflect about that even if the firmware really has that flaw. That is not the way it is done.
The most we can expect is a comment for a firmware update in the line of "improved behavior when GPS lock cannot be obtained".
Nov 16, 2017, 08:52 PM
Registered User
Quote:
Originally Posted by Hullken
Am I the only one thinking that Hubsan might have an office in Ghana and that's where they're getting all those refurbs from?

Better wear my tinfoil hat the next time I go flying.
Lol!

If we could gather compass heading (yaw) and general location info for all the flyaways, we could check if they all point toward 0, 0 coordinates.

OK, people, who else had a flyaway?


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