Speed control and RTH/FAILSAFE improvements

[digitalentity]

• Split auto/manual speed and climb rate limitation
• Remove 2D RTH
• RTH sensor loss refactoring

[oleost]

What does remove RTH 2d mean?

[digitalentity]

Originally it was possible to activate RTH mode if you don't have an altitude sensor - it will just fly home at current throttle without maintaining altitude. I'm taking this away now - it's potentially unsafe and actually useless feature.

[sppnk]

By 'not having altitude sensor' is included GPS altitude?

[digitalentity]

@sppnk "not having altitude sensor" is machine-specific. For quads it's not having barometer sensor. For planes it's not having barometer and not having a GPS fix.

[sppnk]

ok, good to know.

[oleost]

@digitalentity Hmm, maybe the current implmentation was useless.

But even a multirotor would probably get home nicely without barometer and only relying on GPS altitude?

[digitalentity]

@oleost it might. But I feel that having a barometer is benificial for an airplane as well.

[oleost]

@digitalentity Yes.

[Linjieqiang]

Looks great.The code will be cleaner than before.

[digitalentity]

It would be good if somebody can test this code - I'm sick at the moment and unable to fly my birds.

[oleost]

#1475

[Linjieqiang]

Last day I tested it with my wingwing.It looks great but I wonder why my pitch channel didn't work when changing althold mode?Maybe I will test this branch again today.

[Linjieqiang]

Nice today..It didn't have any problem about this operation.

[giacomo892]

Seems like in 1.7 there the "bug" still here @digitalentity despite it has being fixed as this PR and #798

LOG00290.TXT

Using:

set nav_auto_speed = 800
set nav_manual_speed = 1000

I get steady 8m/s in PH CRUISE instead of expected 10m/s as you can see from the logs.

I'm pretty sure I was full pitch when I was a 8m/s and there was no strong wing.

[digitalentity]

@giacomo892 I believe @DzikuVx tested it successfully.

[giacomo892]

@digitalentity you can check for more logs if you need in #1675

[DzikuVx]

@digitalentity No I did not

[digitalentity]

@giacomo892 in your log I see velocity target reaching 9m/s and actual velocity reaching 9m/s as well. Certainly not 8m/s.

Are you sure you have set nav_manual_speed = 1000 ?

[giacomo892]

@digitalentity Maybe it is rounded and there could be some wind. With MWP I mostly see it as 8m/s and some spikes to 9 as you say.

this is the diff I saved on file:

set nav_use_midthr_for_althold = ON
set nav_user_control_mode = CRUISE
set nav_auto_speed = 800
set nav_auto_climb_rate = 350
set nav_manual_speed = 1000
set nav_manual_climb_rate = 400
set nav_mc_hover_thr = 1510

Yes, the diff show it, but to be 1000% sure I'll check it again on friday.

[digitalentity]

@giacomo892 I've just found a bug that prevents manual control from reaching the nav_manual_speed. Speed controller itself is not limited, it's a bug that prevents us from requesting the nav_manual_speed value. With default settings it limits max setpoint to precisely 90% which gives 9m/s max speed at nav_manual_speed = 1000

[giacomo892]

It's nice when I can help spotting bugs. Thanks for your investigation and when you have time please visit #1675 ;)