Problems with wpnav_speed parameter

ArduCopter
1

I’m currently editing wpnav_speed parameter during the flight to change vehicle speed. It works quite well when the vehicle is close to the starting waypoint but as it approaches to target waypoint, it ignores the wpnav_speed parameter (i know it is supposed to slow down as it approaches to target waypoint. What i want to do is slowing down further). So lets say i have a survey mission with line lenghts 400m. Vehicle updates its speed according to wpnav_speed param until approximately 60m before reaching the target wp. Is there a way to make it always respond to wpnav_speed parameter? Im editing the wpnav_speed parameter via lua scripts, same thing happens with set_desired_speed(). Is this a bug or a feature?

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2

Ardurover 4.4 beta11 Qiotek Zealot H7
Im seeing the same behaviour. Its kind of working, then the mower goes further away and it ignores the vehicle:set_desired_speed(0.2) command.

4

I think switching back to loiter mode momentarily (or whatever it is called in rover) and then back to auto mode will fix your problem (it somehow forces it to update that way). I tried same thing in copter and it works but as you can guess it messes up the mission while flying fast. I’m still having this problem as of copter 4.4.4

5

update: Solved my problem. It was related to the nudge from the rc throttle position in auto modes.
When my throttle was in the center position (eg speed middle) it works consistently. Slow and Fast throttles behave differently.

6

Does it also work when you get near waypoints? I always did my tests while throttle was neutral so im wondering if it behaves differently in ardurover?

7

not sure sorry.
i got my script working - its a mower - the petrol motor driving the blade stalls or slows down out if we hit long grass, so if the RPM’s drop - we need to slow down the mower for a bit to get through the long bit.

The mower pulls more current from the alternator on pivot turns (waypoints) so kicks off the slow mode. Its all pretty hard to untangle. I’ve got a bit of tuning to do, so might figure it out, i’ll post anything relevant if i find it. Good luck sorting yours.

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