EKF Flyaway!

[sparkplug23]

Hey guys,

So two days ago I got to experience the joys of a fly away. At the time, I spent a day looking in the fields I thought it went, but after learning how to pull the tlogs from the controller I discovered I was way off. I have lodged a ticket with 3DR and am anxiously waiting to hear back. I know the cause, the EKF limit occurred and the drone simply didnt know which direction was home.

I got the last known position and have spent two days searching around it and downwind from it. The last few seconds (10 fields away from me) the drone switched to AltHold, but still dropped by almost 20ft. The last coordinate had these alt's:

alt:14ft
altasl: 61ft
elev: 88ft​

For reference, it started at:

alt: 0.8 ft
altasl: 47ft
elevation from google: 134ft
​

I am relatively new to all this, so could anyone let me know what the true above ground level height was at that instance. If it was low, the wind would have carried it into trees and I may be able to find it, if its high, the 40% charge could have taken it for miles! It was moving at 22mph when the blackbox stopped.

Thanks guys,

Michael

 

[SteveReno]

Hey guys,

So two days ago I got to experience the joys of a fly away. At the time, I spent a day looking in the fields I thought it went, but after learning how to pull the tlogs from the controller I discovered I was way off. I have lodged a ticket with 3DR and am anxiously waiting to hear back. I know the cause, the EKF limit occurred and the drone simply didnt know which direction was home.

I got the last known position and have spent two days searching around it and downwind from it. The last few seconds (10 fields away from me) the drone switched to AltHold, but still dropped by almost 20ft. The last coordinate had these alt's:

alt:14ft
altasl: 61ft
elev: 88ft​

For reference, it started at:

alt: 0.8 ft
altasl: 47ft
elevation from google: 134ft
​

I am relatively new to all this, so could anyone let me know what the true above ground level height was at that instance. If it was low, the wind would have carried it into trees and I may be able to find it, if its high, the 40% charge could have taken it for miles! It was moving at 22mph when the blackbox stopped.

Thanks guys,

Michael

Sorry to hear your Mishap.
EKF use's many sensors that available to it,
gyroscopes, accelerometer, compass (magnetometer), GPS, airspeed and barometric pressure
measurements

This was the answer to another member here "Aussie in AZ" on what happened. Not a EKF "Flyaway"

From 3DR"
"To sum it up, you lost gps signal and 2 seconds later lost rc signal.
The failsafe for loss of gps puts the copter in altitude hold (fly:manual) and the failsafe for rc signal loss is RTL given it has gps signal or falls back on LAND in case the copter does not have gps.
Technically this wasn't a fly away given a flyaway, at least in my experience, consists of a copter speeding up in a particular direction and often also rising in altitude brought upon by bad sensor readings.
What you have experienced is a combination of two scenarios pulling together in a small window which led to a lost copter"
In any case, they replaced everything, including his H4B

 

[sparkplug23]

Sorry to hear your Mishap.
EKF use's many sensors that available to it,
gyroscopes, accelerometer, compass (magnetometer), GPS, airspeed and barometric pressure
measurements

This was the answer to another member here "Aussie in AZ" on what happened. Not a EKF "Flyaway"

From 3DR"
"To sum it up, you lost gps signal and 2 seconds later lost rc signal.
The failsafe for loss of gps puts the copter in altitude hold (fly:manual) and the failsafe for rc signal loss is RTL given it has gps signal or falls back on LAND in case the copter does not have gps.
Technically this wasn't a fly away given a flyaway, at least in my experience, consists of a copter speeding up in a particular direction and often also rising in altitude brought upon by bad sensor readings.
What you have experienced is a combination of two scenarios pulling together in a small window which led to a lost copter"
In any case, they replaced everything, including his H4B

Thanks for your reply Steve.

From the tlogs I have "Error pos horiz variance" and "EKF" and "Bad compass health". Going by the final data, the "alt" was at 14ft (though terrain was 40ft ish lower again), but it was dropping at a rate of 12fps. Someone must have lifted it because that would have it in the middle of the field. I am crossing every finger hoping it all gets replaced, but even if it does, its so frustrating to think it could have landed without a break and is just sitting in the bushes. It's amazing how impatient you can get when it's something so expensive!

 

[SteveReno]

We all dread that day, perhaps why i bought another one, just out of anticipation.
1 day, it will happen to all... :-( , probability says so.....
Most likely, mines will be lost in saltwater.

 

[sparkplug23]

We all dread that day, perhaps why i bought another one, just out of anticipation.
1 day, it will happen to all... :-( , probability says so.....
Most likely, mines will be lost in saltwater.

Very impressed, issued me with a replacement. I have contacted the original seller with a number to contact 3dr with who will give the okay to ship out a new kit. Result!

For anyone that comes across this I've learnt some valuable things from Hindsight.

• Put your name and number on it!
• Black, is impossible to find, add a some reflective tape.
• I wasted an afternoon searching an area for the drone, when it's last location was nearly a mile away! Learn how to get your tlogs from your controller TODAY. That way, if you have a laptop nearby you can pull your logs off the controller and know the solos last location it sent back, you'll be able to go directly to that site and hopefully pick up signal again to pinpoint it.
• On a rapid flyaway, choose immediate potentially harmful landing over trying to regain control... The time between you trying yo ascertain it's orientation, troubleshoot the flight problem and then hold the land button for 3 seconds on your controller. . . . It's long gone! (mine flew away at 30mph)

As an electronic engineer, I am currently working on a GPS to cellular circuit I can attach to the replacement, I aint losing another one!

 

[ChrisLJ10]

Put this in your new one, it will most likely not lose GPS signal, I have yet to lose GPS signal with it, but lost it a lot with the original one. I've been testing it for about a month now, it's a huge improvement.

mRo GPS u-Blox Neo-M8N (Release 2)

 

[SteveReno]

Very impressed, issued me with a replacement. I have contacted the original seller with a number to contact 3dr with who will give the okay to ship out a new kit. Result!

For anyone that comes across this I've learnt some valuable things from Hindsight.

• Put your name and number on it!
• Black, is impossible to find, add a some reflective tape.
• I wasted an afternoon searching an area for the drone, when it's last location was nearly a mile away! Learn how to get your tlogs from your controller TODAY. That way, if you have a laptop nearby you can pull your logs off the controller and know the solos last location it sent back, you'll be able to go directly to that site and hopefully pick up signal again to pinpoint it.
• On a rapid flyaway, choose immediate potentially harmful landing over trying to regain control... The time between you trying yo ascertain it's orientation, troubleshoot the flight problem and then hold the land button for 3 seconds on your controller. . . . It's long gone! (mine flew away at 30mph)

As an electronic engineer, I am currently working on a GPS to cellular circuit I can attach to the replacement, I aint losing another one!

Wow, ok good deal.
3DR has been giving good service from day 1.

 

[Aussie in AZ]

I can attest to what SteveReno said as it was I that also experienced the EKF problem. I have been flying my newly replaced Solo and H4B for a few weeks now thanks to 3DR customer service. For a company that has fallen on tough circumstances, their customer service is still responsive and second to none.

Cheers
Aussie

 

[mjbnz]

Put this in your new one, it will most likely not lose GPS signal, I have yet to lose GPS signal with it, but lost it a lot with the original one. I've been testing it for about a month now, it's a huge improvement.

mRo GPS u-Blox Neo-M8N (Release 2)

Thanks for that - bought one myself.