Posted 5/31/2021 22:10 (#9036072) Subject: Tune NAV II on a 4430 patriot for better line acquisition
This year autosteer is really driving me crazy. The Trimble NAV II controller has never worked that well for me on any machine, but this spring is particularly agonizing. The problem is acquiring and smoothly turning into a line. Usually I kind of try to get the line on the screen to be about in the middle of the little sprayer graphic as I'm turning into the line and it works okayish. The little map makes it hard to know how close you really are. Last year if I was not quite close enough, the sprayer would turn immediately towards the line, acquire it, and more or less get on track in short oder. This year, about a third of the time, the sprayer will wait too long to turn, then turn sharp, then over-correct and otherwise drive like a drunk person for a couple of oscillations on the line . If I take over the wheel for a second and re-engage, it drives fine. A couple of times it missed the line altogether and gave up when I engaged as I turned into the line. One time I stopped driving when I knew it was close to the line but overshooting it, backed up, turned on autosteer and tried again. And it basically followed the exact same wavy path even though I had started very near the line. Now I would be tempted to consider that the inertial steering angle sensor is having issues, but in fact if I have my boundaries and headlands set up, AccuTurn can make turns all by itself and accurately acquire the line without fuss, so it clearly knows where what the steering angle is. This leads me to think it's a tuning issue with the NAV controller itself.
Any tips for tuning this thing? I realize the path planning algorithm is pretty primitive and seems to involve just tracking and heading errors, exclusively. But I know it can do a better job than it is doing now. Any help is appreciated. Right now everything is at default settings in NAV-P and NAV-S. I've tweaked a few settings but have never made anything better.