@rmackay9
Thanks for your reply.
Yes, 4 times more Snow than usual in Europe.
I made some tests before my post and thats why I came to my proposition.
Instead of 2m it stopped at 0.45m.
Log: Test 13.bin - Google Drive
But I will make more test to see your advice with better GPS connection.
And use a lightweight obstacle in case of… because I would like to reduce the target distance.
I managed at last to run the Quick Tune today.
Could not have got here without everyone’s help…thank you.
It went very well. I found the instructions easy to follow and very informative. Never run a lua script on ardurover until today.
Acro mode after the Quick Tune worked well.
Tried some simple missions after tuning and found that it kept stopping at some of the
way points. I changed Waypoint Pivot Angle to 0 and bingo. It was doing very nice 2m radius turns effortlessly with maybe a slight acceleration in the turn after that.
More to do but very happy.
Thank you all again.
Hi @Fossil,
Thanks very much for the feedback. Yes, the vehicle will stop at waypoints if the angle of the corner is greater than the WP_PIVOT_ANGLE parameter or if the waypoint command’s delay field has been set to 1 or higher (seconds).
By the way, when it was stopping at the corners did it pivot OK towards the next waypoint? … and how was it holding the line after the pivot?
There is actually one more potential improvement we could make to the pivot turns which is to remove the turn controller’s “I-term build-up” after it completes the turn. There can be a lot more friction when pivoting which means that the turn controller needs to work really hard to spin the vehicle around. When it does that the “I-term” builds up and it takes some time for it to reduce and that can lead to a wobble after the turn.
@rmackay9, this is exactly what I will be watching for when I do my own testing. Went down another project’s rabbit hole this week and so still need to get beta11 on my machine. Will make an effort to get that done this weekend!
Thanks for your feedback @rmackay9. That would explain it. My WP angle was approximately 90 degrees and WP_PIVOT_ANGLE was set to 60 degrees.
The Rover did the turn well but just sat there pointing to the next waypoint. If I stopped the mission and then restarted it, it would carry on to the next point and do the same again.
I will experiment with pivot turns but at the moment I am looking for nice smooth turns with a large radius for mowing.
Initial results very promising!
I reset PSC params to defaults prior to this session.
That first half circle had some big bumps, so I offset a little before initiating QuikTune. It completed quickly and with little issue, though I think my circle radius might have been on the ragged edge of too large (a couple of warnings to “increase steering”).
First auto mission looked pretty solid. Brief log review shows that STER.DesTurnRate may be overshooting a little, but the data is noisy (likely a combination of rough terrain and machine vibration).
I’ll run a longer mission as soon as I finish typing here and report any further findings and/or manual refinements of the tuning.
Log file (anon) linked here. Can provide .bin privately upon request.
(and yes, I still have arming checks disabled…I really ought to employ a solution to that…)
UPDATE (while the longer mission runs):
Based on my log review and observation during the mission, I made some very small tweaks to the autotuned values (mostly just rounding them slightly up or down from the long decimal values) and may have gotten slightly better results. I’m not sure anything I did there was meaningful enough to warrant changing the QuikTune script. Noticed I had some lingering D-term values as well, so zeroed those, since it appears QuikTune doesn’t touch them anymore (comment at the top of the script probably needs an update).
Also reset TURN_MAX_G and WP_RADIUS to defaults, which smoothed S-Curves from a more aggressive setting I had tried previously.
I’ve noticed that both the L1 controller and PSC controller seem to misbehave just a little bit after a scripted speed change. The vehicle always wanders a little before correcting back to track after a speed change (particularly when slowing). That behavior is much improved in beta11, but I wonder if that might be a similar term buildup that @rmackay9 mentions regarding post-pivot oscillation?
On the topic of pivots, I didn’t notice much oscillation after turns, but I did see that x-track error was worst at the beginning of any given segment, so there may be merit to zeroing or damping the I-term as suggested.
To how many decimal places did you round them down/up?
I had two values that had about 8 decimal places.
The long decimal values are not a problem, per se. I noticed some minor steering overshoots in the log and rounded to 2-3 decimal places as a means of tightening the tune slightly.
It’s not necessarily best practice to simply round the values because they are visually displeasing.
I don’t find them displeasing at all. It crossed my mind that these values may increase the processing power required. If not then I am more than happy to leave alone until I have a better understanding of what rounding them up or down would do.
No. Additional displayed digits have no bearing on CPU or memory load. They are stored as 16 or 32 bit values, and the same number of bits/bytes are processed regardless of how the numbers are presented in human readable form.
Thank you for the explanation Yuri. Unfortunately I am none the wiser!
I will leave well alone and trust the Quick Tune process for now.
One day I may understand software…but I doubt it.
Thank you Randy, I will give this a try
Hello @rmackay9, I have a vector thrust jetboard that will be running at 30 knots, the board itself is quite big around 1.5m length, and weigh about 30-40kg. It is using with a cube orange, would it be a good idea to test it with QuikTune?
Hi @zhe0201,
It could be. It really depends on how well you’ve managed to tune it yourself. If you haven’t tuned it at all then the QuikTune will likely improve it. If you have a log I’m happy to have a look at it.
thanks! I am going out to do my first tuning tomorrow. Will share the log once I get it.
Thanks Randy and team, i upgraded to 4.4 beta11 and ran the auto-tune script.
I haven’t downloaded the log or looked in too far but the lines its now mowing are excellent. Cross track error is well within 50mm and mostly 10-20mm. The tune messed up the speed pids - (bucking bronko) so needed a quick manual tune.
Video of mower driving round and round here.
The Tune does not complete on my craft
Hi @John_Easton,
I think the issue is that the boat probably cannot achieve a 10deg/sec turn rate. It should have displayed a warning on the ground station if I’m right.
Yes Randy, she is a semi-submersible with a lot of ballast.
As seen here in this video - https://www.facebook.com/reel/311835715145595
I am quite happy with her navigation except for the over throttle in the turn resulting in a major oversteer.
If I can get a handle on this section of the throttle I believe she will be perfect.
