So I was finally able to do a test today with change WP Nav speed in flight-(I think it was me @dkemxr in another thread that hinted it was still working), and in short it is still working…sort of. I was certainly able to change speed between waypoints using Ch6 however the reaction to the speed changes were a little unpredictable, sometime working straight away, sometimes having to wait a bit. It would be great if this could be made to work with a good reaction time to the RC input by the pilot. The firmware I am running and did the test on is 4.1.3
Log showing WPNav Spd on Ch6 working (kind of)
Hi Angus-Yes I think it was your thread we were discussing this. I would like to review the log as I was going to do some testing but the link looks broken. Can you check it out?
2 things. The max/min values are in dekameter/sec I believe. So these values are way out of range.
TUNE_MAX,2500
TUNE_MIN,100
But, when I test WP Nav Speed on the bench from the Extended Tuning page by varying the Tune Pot and then hitting the Refresh Screen button I don’t see the WPNav Speed value change on the screen. If it doesn’t change there It won’t update the Autopilot.
I just ran an Auto Mission V4.2.0-beta2 with Min/Max set for 750-2000 cm/s and I don’t see the Chan 6 Tune for WP Nav Speed working at all.
Yeah, I noticed too that the refresh didn’t update the speed on the Extended tuning page but clearly it does work to a degree in the air. I think the units are the same as for the WP Nav speed as I was getting a crawl of approx 1m/s when set to the min. Its unclear. To be honest, the whole unit thing in Ardupilot is a bit messed up although I am sure there is good historical reasoning for it. I mean who works in cm/s etc? 
I can’t tell from your log if it’s working or not. No sustained speed and it’s switching from Auto to Loiter a bunch. Run a there and back Mission with some distance and vary the Tune along the way.
Presentation1.pdf (413.1 KB)
This shows it working I think. WPnav speed set to 5m/s in standard params but clearly going a fair bit faster once Ch6 set to full. I will try and get a longer run to try this out to get more data.
I don’t think it is actually. But raised an issue in any case for review.
To get back on this you are right it is working and the tune max/min units are in cm/sec.
But there is a low limit below which it won’t function. This was where I was wrong by using the wrong units and it was below this threshold.