Hi,

Checked the failsafe 50 meter backtack of the Mini 3 Pro.
Plus 2 RC, 2 hands   it is possible to do.....   ;-)



cheers
JJB

If the home point is higher, i.e. on the mountain. Then when returning home from a distance of 20m, when it is below the home point, the drone will stop at the foot of the mountain.
When you press the return home button.

I think it would be interesting to shoot a video which included height changes in the last 50m, e.g. with the RTH height set to the minimum start a steep descent from well above the RTH height to below the RTH height and for another test to do the reverse. I haven't been in a position to test that with the Mini 2 etc..

Drone.Hunter Posted at 11-26 07:39
If the home point is higher, i.e. on the mountain. Then when returning home from a distance of 20m, when it is below the home point, the drone will stop at the foot of the mountain.
When you press the return home button.

i know, made a video of that.

User initiated RTH or FailSafe RTH wich starts < 50 ( for a Mini3Pro ) meter away from HP, drone will stop at an obstacle and will not rise above the obstacle !!
This way a drone can be lost....in failsafe (no connection) drone hovers and hovers...if out ot physical reach....you loose...

IMO we all need to know this,  mayby needs a change in the FlyApp.
https://forum.dji.com/forum.php?mod=viewthread&tid=276940

Sean-bumble-bee Posted at 11-26 07:53
I think it would be interesting to shoot a video which included height changes in the last 50m, e.g. with the RTH height set to the minimum start a steep descent from well above the RTH height to below the RTH height and for another test to do the reverse. I haven't been in a position to test that with the Mini 2 etc..

oops   difficult to read...

RTH height to minimum = 20 meters for a Mini3 pro.
Steep decent...and disconnect below 20 height.

Do you think / expect that the drone will back track and climb ?

cheers
JJB

JJB* Posted at 11-26 08:29
i know, made a video of that.

User initiated RTH or FailSafe RTH wich starts < 50 ( for a Mini3Pro ) meter away from HP, drone will stop at an obstacle and will not rise above the obstacle !!

From a distance of less than 50m, we are unlikely to lose the drone. Maybe it’s necessary so that the drone doesn’t crash anywhere along the road?

Drone.Hunter Posted at 11-26 08:40
From a distance of less than 50m, we are unlikely to lose the drone. Maybe it’s necessary so that the drone doesn’t crash anywhere along the road?

depends...

In my country we have dikes....and water....

If i fly lower than start point over water and loose connection, it is possible to that my drone is trapped to a dike wall, out of reach.

Fly into a canyon, and loose connection flying height -20 meters and horizontal distance to home < 50 meters,  drone bumps into wall and you loose....

cheers
JJB

JJB* Posted at 11-26 08:44
depends...

In my country we have dikes....and water....

You are scaring me. If communication can be lost at 50m, then there are very difficult conditions. And it is probably safer not to move, but for the pilot to look for an opportunity to improve his position in order to create a stable connection.

JJB* Posted at 11-26 08:33
oops   difficult to read...

RTH height to minimum = 20 meters for a Mini3 pro.

suggested flights, both with RTH set to 20m.
Flight 1)  send the drone up to say 60m and well away from the home point. Once at height move the drone slowly across your field of view whilst bringing it down as quickly as possible .... with the aim of getting it under the RTH height by the time the drone has moved 50m horizontally. Once below the RTH height trigger the fail safe.
The objective being two things, a) will it climb through the RTH height during the 'backwards'/retrace and b) will it actually climb all the way to 60m.

Flight 2) Climb steeply from below the RTH height whilst moving drone across your field of view so that it reaches say 60+m by the time it has travelled 50m horizontally, once up there trigger the fail safe. The objective being to test whether it will descend to below the RTH height and then, in RTH, climb to the RTH height.
Yes I would hope the drone will climb or descend, as appropriate, along the original flight path but I have not been in a situation where I had the space to test this.

This stemmed from seeing a video of someone flying their drone down into a power station cooling tower. It made me wonder what would happen with the likes of a mini 2 or a drone with OA switched off, (this assumes GPS was not lost) would the drone reverse the original inbound flight path in 3D and climb out of the tower as part of its 'backwards' flight etc.

I also have a path suggestion. Have someone else video while you fly. Station them about 150 meters in front of you. Fly to about 25 meters to the Left of them and 25 or so meters in front of them(for a good video shot frame). Traverse L to R directly in front of and perpendicular to them for about 70 meters then disconnect RC. You can repeat same while changing altitude as Sean suggested.
A small addendum - you could also traverse 25 meters and turn 30 degrees for 30 or 40 meters to check if it follows the path or straight line.

Much fun

Sean-bumble-bee Posted at 11-26 09:55
suggested flights, both with RTH set to 20m.
Flight 1)  send the drone up to say 60m and well away from the home point. Once at height move the drone slowly across your field of view whilst bringing it down as quickly as possible .... with the aim of getting it under the RTH height by the time the drone has moved 50m horizontally. Once below the RTH height trigger the fail safe.
The objective being two things, a) will it climb through the RTH height during the 'backwards'/retrace and b) will it actually climb all the way to 60m.

if i have time i will try it....

my guess:
1) will it climb to 60 meter, no  don`t think so as in your scenario the failsade activated below 20 meter.
2) don`t think it will descend back tracking

cheers
JJB

Drone.Hunter Posted at 11-26 08:58
You are scaring me. If communication can be lost at 50m, then there are very difficult conditions. And it is probably safer not to move, but for the pilot to look for an opportunity to improve his position in order to create a stable connection.

it can be reality !

What is the change of loosing connection and not be able to re-connect ?
Reading for many years posts on this forum, change > 0 % ....

cheers
JJB

Sean-bumble-bee Posted at 11-26 09:55
suggested flights, both with RTH set to 20m.
Flight 1)  send the drone up to say 60m and well away from the home point. Once at height move the drone slowly across your field of view whilst bringing it down as quickly as possible .... with the aim of getting it under the RTH height by the time the drone has moved 50m horizontally. Once below the RTH height trigger the fail safe.
The objective being two things, a) will it climb through the RTH height during the 'backwards'/retrace and b) will it actually climb all the way to 60m.

Hi Sean,

did some other tests today, and one Failsafe RTH test.

RTH height set to 20 meter.
From 60 meters to 10 meter and at 10 meter height (>50 meters away from HP) : RC off.
After few seonds RTH in progress, UH? ; just vertical climb to RTH setting and straight flight towards HP.

Oke, need to do more. Does a drone fly 50 meters back on track only when that 50 meters was flown at one height??

cheers
JJB

JJB* Posted at 11-28 07:35
Hi Sean,

did some other tests today, and one Failsafe RTH test.

Beep beep that's worrying, possibly dangerous (to the drone) and not as I understand the Mini 3 manual. (I can only go by the manual as I do not have a Mini 3 and I doubt I will get a mini 3 until the second hand prices drop, I think they are simply far too expensive for what the drone is. As a joke size matters lol.

From the 1.4 wersion of the manual, which is the latest version I can find, it says  

".....ude. If the aircraft is more than 50 m from the Home Point when the remote controller signal is lost, it will fly backwards for 50 m on its original flight route" which should seemingly have included a climb from 10m to 60m "and then enter Straight Line RTH. The aircraft will enter or remain in Straight Line RTH if the remote controller signal is restored during RTH.
After flying backward on the original route for 50 m:
1. If the aircraft is 50 m or less than 50 m from the Home Point, it will fly back to the Home Point at its
current altitude."    Not the situation in your test.
"2. If the aircraft is further than 50 m from the Home Point and the current altitude is higher than the
preset RTH altitude, it will fly back to the Home Point at its current altitude.."    Not the situation in your test.
"3. If the aircraft is further than 50 m from the Home Point and the current altitude is lower than the
preset RTH altitude, it will ascend to the preset RTH altitude and then fly back to the Home Point." could this be the reason, could it (straight line RTH behaviour) over ride the " fly backwards " section because the drone is below RTH height? *


When the drone was descending did you move it horizontally at all?

*What happens if you set the RTH height at 20m then fly out to beyond 100m (to be well clear of the 50m boundary)  at a height of 10m and then fly left or right for some distance at a height of 10m and initiate a failsafe RTH? Does it retrace horizontal flight at 10m before starting the climb to RTH height?

Sean-bumble-bee Posted at 11-28 11:41
Beep beep that's worrying, possibly dangerous (to the drone) and not as I understand the Mini 3 manual. (I can only go by the manual as I do not have a Mini 3 and I doubt I will get a mini 3 until the second hand prices drop, I think they are simply far too expensive for what the drone is. As a joke size matters lol.

From the 1.4 wersion of the manual, which is the latest version I can find, it says  

Hi,

#3 is picked after the previous text "After flying backwards on the original route for 50m:....

Thus, i.a.w. manual it should fly back first.  wich i did not do!

Uh, text saying "on the original route", not  "on the original route and height"....

My test was flying from 60 meters baro height to approx 10 meters height, over a distance of 80 meters or so, so did try a steady line forward+down.

Interesting, so if weather permits do some more tests on this issue

BTW  Mini3Pro is great drone, easier to fly than a Mini2 (softer on the RC controls), imo worth every penny!Think i will sell my Mini2.
Love the RC, only you need more precision in pointing RC to the drone. No distance issues as i normally don`t fly out to far....   ;-)
RC compass....fun, if i rotate 2x 360 `s  (while in flight) compass indication is spot on.

cheers
JJB

JJB - Interested data points.

And I loved your comment about not flying out too far!

JJB* Posted at 11-28 11:59
Hi,........Uh, text saying "on the original route", not  "on the original route and height"....

I think we may have a difference of opinion of the what "flight route " means, to me it is the path flown in three dimensions, do you consider it to be two dimensional?

But even if the drone is just supposed to retrace the route in 2D as I understand your post 15 it did not do that, am I correct?

Sean-bumble-bee Posted at 11-28 13:47
I think we may have a difference of opinion of the what "flight route " means, to me it is the path flown in three dimensions, do you consider it to be two dimensional?

But even if the drone is just supposed to retrace the route in 2D as I understand your post 15 it did not do that, am I correct?

i never really had a thought about "flight route"....

But what was the difference between the 2 FailSave RTH tests.

Flying at one heigt : discoonect = fly backwards on the route for 50 meters
Flying form some heigt to low height : disconnect = acsend to RTH height setting, fly direct to HP

Will do, weather permits, some more tests about this.

I think DJI did not implement the height changes into the fly backwards route.

cheers
JJB

Sean-bumble-bee Posted at 11-28 13:47
I think we may have a difference of opinion of the what "flight route " means, to me it is the path flown in three dimensions, do you consider it to be two dimensional?

But even if the drone is just supposed to retrace the route in 2D as I understand your post 15 it did not do that, am I correct?

Hi,

tested the fly back disconnect today on my Mavic Air2.

3 times tested, after each disconnect it flewy back 50 meters....and did not only back on track but also corrected the height to what i had flown.
oops  mistake   4 times tested, flying high to low it did backtrack.(thanks to screen recording, refeshing my memory...) [ SD card pushed in the MA with cold fingers, popped out , glad that the plastic cover was closed oke ]

Pleased with the results, but why one time not ?  (mayby to low height at disconnect ?)
Next time the Mini3 pro!


cheers
JJB

Cool.......