RTH - A Couple of Questions

[StubbornSwiss]

Greetings!

Concerning the Low Battery RTH - from my own experience this warning kicks in at around 20% battery, and is initiated after a 10 sec. countdown.
1/ Is this 20% a fixed number, or is dependent on how far away the drone is, and therefore how much battery it will actually need to get back to the home point?
2/ If the Low Battery RTH is cancelled, at what battery percentage will it initiate an auto-landing, or again is this dependent on its height and therefore how much battery in will need to descend and land?
3/ The attached is a snippet from page 14 of the manual. What flight parameters can we control using the DJI Fly app?



Thank you good people.

 

[Meta4]

1/ Is this 20% a fixed number, or is dependent on how far away the drone is, and therefore how much battery it will actually need to get back to the home point?

It will vary with the distance your drone from the home point.
Each 1/10th of a second the drone is monitoring distance and battery levels to calculate how close your drone is to having to turn back.

is this dependent on its height and therefore how much battery in will need to descend and land?

Height and the required time to descend are factored in.
But that is based on height above the home point, the drone cannot know if you have flown off a high point and the ground is now much further below.

3/ The attached is a snippet from page 14 of the manual. What flight parameters can we control using the DJI Fly app?

As it says .. the aircraft’s speed, altitude, and the orientation can be controlled using the remote controller.
You can use the joysticks to vary those during RTH.

 

[StubbornSwiss]

@Meta4 thank you for an excellent reply. Totally clear.

However, point #3. The manual says we can control it using the remote controller OR the the DJI Fly app. Should I consider this to be just a typo?

 

[sar104]

It will vary with the distance your drone from the home point.
Each 1/10th of a second the drone is monitoring distance and battery levels to calculate how close your drone is to having to turn back.

Height and the required time to descend are factored in.
But that is based on height above the home point, the drone cannot know if you have flown off a high point and the ground is now much further below.

As it says .. the aircraft’s speed, altitude, and the orientation can be controlled using the remote controller.
You can use the joysticks to vary those during RTH.

SMART_BATTERY.goHomeBattery is the battery level parameter at which the FC will attempt to initiate RTH, and it is based only on distance from the home point, not height. SMART_BATTERY.landBattery is the battery level parameter at which autoland kicks in, and it is calculated purely on height above takeoff.

 

[StubbornSwiss]

OK, noted with thanks. So my next question is then not necessary. I was going to ask if the RTH point in any way took into account the wind speed/direction. But I see it is based solely on distance. Thanks @sar104.

 

[EyesWideShut]

@Meta4 thank you for an excellent reply. Totally clear.

However, point #3. The manual says we can control it using the remote controller OR the the DJI Fly app. Should I consider this to be just a typo?

It is as Meta4 quoted from the manual "As it says .. the aircraft’s speed, altitude, and the orientation can be controlled using the remote controller. "
During RTH you can climb, descend, speed up, slow down and yaw. The only thing you can't do is change the direction/course... it is flying straight home. It's great to experiment with, you can set your home point and use it almost like a waypoint. Good for video where you don't have to worry about the course and can pan/climb/slow down etc.

 

[StubbornSwiss]

It is as Meta4 quoted from the manual "As it says .. the aircraft’s speed, altitude, and the orientation can be controlled using the remote controller. "
During RTH you can climb, descend, speed up, slow down and yaw. The only thing you can't do is change the direction/course... it is flying straight home. It's great to experiment with, you can set your home point and use it almost like a waypoint. Good for video where you don't have to worry about the course and can pan/climb/slow down etc.

Yes, I understand that, thanks. But please have a look at the screenshot. That is page 14 of the manual. It says ".... the aircraft’s speed, altitude, and the orientation can be controlled using the remote controller or DJI Fly....".
Surely you see that @EyesWideShut ............. but then again, with eyes wide shut, maybe not ? ?

 

[EyesWideShut]

I must of blinked reading that about the Fly app... I have used the FC sticks to alter RTH as I said above.
Just some thoughts here:
1.Haven't yet tried to use the app display to switch out of the default RTH P mode to Sport or Cine mode, just used the forward throttle to adjust. Helpful to boost the RTH speed. DJI might have fixed that in this new firmware because it din't use the highest speed the mini was capable of in it's RTH.
2. Maybe we can update a new home point during RTH or is it locked in...
3. You can change the camera tilt on the Fly display by tapping on the display and swiping the vertical gauge.
I'll have to wait till tomorrow to try some things.

What ideas do you guys have??

 

[DanMan32]

It does sound strange the manual would say it could be controlled by the app. Perhaps whoever wrote the manual was tired and assumed that since the Mini uses Wi-Fi for control, it can also be piloted by the app rather than the remote. Some models can connect directly to the phone through Wi-Fi and piloted through the app.

That or they confused manually activating RTH which can be done from the remote or the app, versus flight controls while in RTH. There's very little if any flight functions one can do with the app while in RTH.

 

[StubbornSwiss]

See...... I got you to open them shut eyes!!!

Anyways, thanks for the pointers on using the RTH, with homepoint as a waypoint. So basically I can fly a course sideways all the way, being freed up to do some fancy filming! Must try that out tomorrow.

Stay safe, and thanks again.

 

[Meta4]

Yes, I understand that, thanks. But please have a look at the screenshot. That is page 14 of the manual. It says ".... the aircraft’s speed, altitude, and the orientation can be controlled using the remote controller or DJI Fly....".

Obviously you can't change much about the listed points with the app.
But DJI's documentation is full of confusing, poor wording.
I wouldn't get too excited about this one.

 

[Thomas B]

It does sound strange the manual would say it could be controlled by the app. Perhaps whoever wrote the manual was tired and assumed that since the Mini uses Wi-Fi for control, it can also be piloted by the app rather than the remote. Some models can connect directly to the phone through Wi-Fi and piloted through the app.

That or they confused manually activating RTH which can be done from the remote or the app, versus flight controls while in RTH. There's very little if any flight functions one can do with the app while in RTH.

Most likely a poor translation of the original Chinese version.

 

[DanMan32]

I must of blinked reading that about the Fly app... I have used the FC sticks to alter RTH as I said above.
Just some thoughts here:
1.Haven't yet tried to use the app display to switch out of the default RTH P mode to Sport or Cine mode, just used the forward throttle to adjust. Helpful to boost the RTH speed. DJI might have fixed that in this new firmware because it din't use the highest speed the mini was capable of in it's RTH.
2. Maybe we can update a new home point during RTH or is it locked in...
3. You can change the camera tilt on the Fly display by tapping on the display and swiping the vertical gauge.
I'll have to wait till tomorrow to try some things.

What ideas do you guys have??

I don't think you could ever exceed normal mode max speed with any of DJI's models. You had to go to sport mode to do that. We've recommended going to sport mode if winds prevented you from making headway.

 

[DanMan32]

See...... I got you to open them shut eyes!!!

Anyways, thanks for the pointers on using the RTH, with homepoint as a waypoint. So basically I can fly a course sideways all the way, being freed up to do some fancy filming! Must try that out tomorrow.

Stay safe, and thanks again.

Much like a poor man's course lock.

 

[DanMan32]

... Or tapfly.

 

[StubbornSwiss]

Ok..... I think that settles it.

As usual my questions are all answered, and I continue to learn.

Thank you all, and please keep safe.