Landing

[Logger]

Same Event but showing control mode switch position. Purple = P, Teal = Sport.

 

[Logger]

@Andrew F had reported that autolanding (I assume he meant the FORCE_LANDING state) was cancelled while below 0.5 meters

I don't think that's possible. If it is though, that's a flight log we should check out.

I guess you were meaning not possible by way of throttle trigger. Because it is possible to cancel below 0.5m with the mode switch.



1 second of full down throttle at 0.5m triggers FORCE_LANDING. 0.5 sec later descent has commenced and at 0.4m I toggle mode switch cancelling FORCE_LANDING.

 

[Anthonyk]

Will hitting pause button stop the landing ?

 

[msinger]

I guess you were meaning not possible by way of throttle trigger.

Yes, that's what we were discussing above.

 

[BudWalker]

I tried to duplicate @Andrew F 's results by turning off various parts of the vision system. The closest I came was when Landing Precision was turned off. Full negative throttle made it land gently but it didn't actually switch to the FORCE_LANDING state. So, this isn't fully identical to @Andrew F 's data.

I guess it's time to ask. @Andrew F what firmware are you running?

 

[Andrew F]

I tried to duplicate @Andrew F 's results by turning off various parts of the vision system. The closest I came was when Landing Precision was turned off. Full negative throttle made it land gently but it didn't actually switch to the FORCE_LANDING state. So, this isn't fully identical to @Andrew F 's data.

I guess it's time to ask. @Andrew F what firmware are you running?

I WAS running older firmware. But I just upgraded yesterday to latest. I'll check again in a few minutes and post. I think it's worth ferreting out what's going on here. In my mind, we SHOULD be able to cancel autolanding anytime we want. Horrible if they removed that.

 

[Andrew F]

I WAS running older firmware. But I just upgraded yesterday to latest. I'll check again in a few minutes and post. I think it's worth ferreting out what's going on here. In my mind, we SHOULD be able to cancel autolanding anytime we want. Horrible if they removed that.

So it turns out that DJI removed the abort option in the latest firmware upgrade. UGH. We NEED to be able to abort autolanding. They NEED to add this back. I'm downgrading to .04 to see if I can get it back. But I think I was running .02 before.

 

[Andrew F]

I just verified that Mavic firmware .04 ALLOWS autolanding abort. I will stick with .04 until DJI rectifies in future firmware upgrades.

 

[BudWalker]

I just verified that Mavic firmware .04 ALLOWS autolanding abort. I will stick with .04 until DJI rectifies in future firmware upgrades.

I feel your angst over this. There are other methods of retaining the ability to cancel FORCE_LANDING while using the latest firmware. As @Logger mentioned earlier switching modes between Sport and P seems to cancel FORCE_LANDING. Another method is to disable Landing Protection in the Advanced Vision Settings . I've tried this and it seems to have minimal effect and the Mavic will gently land itself while full back throttle is applied.

There may be good reason pilot stick input is ignored during FORCE_LANDING. During FORCE_LANDING a different control loop is in effect which is much tighter than other control loops (e.g. an RTH or critical battery landing).There just isn't enough bandwidth to accept stick inputs. Think of an RTH like driving around a parking lot looking for a parking spot. The driver can accept instructions to go down this aisle or that hoping to find just the right spot. FORCE_LANDING is more like changing lanes on a busy freeway; the driver just doesn't have enough bandwidth to accept directions from the passenger while changing lanes and still be safe. BTW, I've tried using this explanation as in "I'd like to listen to you but I'm in a really tight control loop and I don't have the bandwidth". I've had mixed results with this approach.

 

[Andrew F]

I feel your angst over this. There are other methods of retaining the ability to cancel FORCE_LANDING while using the latest firmware. As @Logger mentioned earlier switching modes between Sport and P seems to cancel FORCE_LANDING. Another method is to disable Landing Protection in the Advanced Vision Settings . I've tried this and it seems to have minimal effect and the Mavic will gently land itself while full back throttle is applied.

There may be good reason pilot stick input is ignored during FORCE_LANDING. During FORCE_LANDING a different control loop is in effect which is much tighter than other control loops (e.g. an RTH or critical battery landing).There just isn't enough bandwidth to accept stick inputs. Think of an RTH like driving around a parking lot looking for a parking spot. The driver can accept instructions to go down this aisle or that hoping to find just the right spot. FORCE_LANDING is more like changing lanes on a busy freeway; the driver just doesn't have enough bandwidth to accept directions from the passenger while changing lanes and still be safe. BTW, I've tried using this explanation as in "I'd like to listen to you but I'm in a really tight control loop and I don't have the bandwidth". I've had mixed results with this approach.

I tried switching to Sport mode and it still wouldn't let me abort. I'm gonna stick with .04 until the firmware allows abort.

 

[Logger]

Will hitting pause button stop the landing ?

Just tried. Does not work. Neither by pickling the switch multiple times or holding pause continuously. Good suggestion though.

 

[Logger]

I tried switching to Sport mode and it still wouldn't let me abort. I'm gonna stick with .04 until the firmware allows abort.

I am curious, what OS and app version. I am running android Go4 v4.0.5. And firmware .005, all VPS related options on. Given that you are running an old firmware by choice I was wondering if you might also be running an early model Go4.
I was having weird VPS issues with Go4 v4.0.4 that have seemingly fixed on 4.0.5.

 

[Logger]

An interesting aside to cancelling Forced Landing using the Mode switch toggle. It works all the way down to the ground and even after landing (prior to rotor cutout timer). Aircraft will fly straight back up to 0.5m and hover.

 

[Andrew F]

An interesting aside to cancelling Forced Landing using the Mode switch toggle. It works all the way down to the ground and even after landing (prior to rotor cutout timer). Aircraft will fly straight back up to 0.5m and hover.

Can you explain exactly what you mean by mode switch? You mean the app made switch? Kinda slow to do if so.

 

[Logger]

The mode switch on the RHS of your RC. Quick and easy to access in an instant.

PS. I have NFI what you mean by " app made switch"

 

[Logger]

View attachment 8853
The mode switch on the RHS of your RC. Quick and easy to access in an instant.

What version of Go4 are you running?

 

[Andrew F]

I am curious, what OS and app version. I am running android Go4 v4.0.5. And firmware .005, all VPS related options on. Given that you are running an old firmware by choice I was wondering if you might also be running an early model Go4.
I was having weird VPS issues with Go4 v4.0.4 that have seemingly fixed on 4.0.5.

I was actually testing on Go 3 and a Samsung. But it is the Controller that matters for what I was testing.

 

[Andrew F]

View attachment 8853
The mode switch on the RHS of your RC. Quick and easy to access in an instant.

PS. I have NFI what you mean by " app made switch"

View attachment 8853
The mode switch on the RHS of your RC. Quick and easy to access in an instant.

PS. I have NFI what you mean by " app made switch"

As I said above, the sport mode did NOT make a difference for me. It did not allow me to interrupt the autolanding.

 

[Logger]

You would think so wouldn't you. But honestly your test environment is atypical, running a Go App that is at least 5 builds out of date.

 

[Andrew F]

You would think so wouldn't you. But honestly your test environment is atypical, running a Go App that is at least 5 builds out of date.

Well, I'm done testing at this point because .04 works well. The app is irrelevant as all inputs were RC but you're correct it's not optimal. There are now videos on YouTube documenting this lack of abort behavior. It's the firmware. Plain and simple.