Hello, I am very glad to join the community of AgOpenGPS.
My setup is:
WAS + ADS,
and I don’t use any IMU.
I have mounted a coulter on the back of my tractor and set the tool’s width at 2m, so after U-Turns the marks after the coulter should be exactly every 2 meters. And the problem is that they ain’t.
On the display i could see that AgOpen knew about that he was driving next to the line but did nothing to fix that.
So, after driving for some time and doing some U-Turns, I measured the distances between the marks and it was regular pattern: 1,8m; 2,2m; 1,8m; 2,2m and so on.
I would be very grateful for every suggestion how can I fix my problem.
Sounds like a calibration issue to me. Could you first clarify if you have observed this behaviour by measuring the coulter marks or can you also see AOG indicate a constant offset from the wayline?
Obvious issues that cause this kind of behaviour are the GNSS receiver position (not centred or incorrect left/right measures stored at AOG settings) or the inclinometer calibration. Obviously also if the implement is not centred or the implement parameters are incorrectly set.
I have not faced the wheel angle sensor calibration issue (have always had it tuned well enough) but I’ve read from the forum that AOG can drive at a constant offset from the wayline if the WAS calibration is off.
NorthernFarmer: This behaviour can be also observed in AOG. If the the problem was about inclinometer, would the “sidehill draft gain” be relevant? GNSS receiver is placed in the center of the hood (I tried also placing it on the roof, but it was only worse). WAS is based on a linear potentiometer mounted to the hydraulic cylinder and the calibration has been done.
Baraki: I have got an electric motor and I have tested a lot of Minimum PWM’s settings from around 40 to 90 and it didn’t help.
Setting sidehill draft gain for around 15-20 makes the tractor drive very far (50 cm) from the line, so it’s making it even worse, maybe due to incorrect inclinometer calibration.
I will try to eliminate diffrent error sources, as you have written.
While driving try what happen if you change steer point zero. Normally AOG hits then the line. E.G. If you are always left side from the line try to do the steer point zero to the right. And important, the wheel angle sensor construction isn’t allowed to “wobble”.
If AOG then hits the line (driving in both directions) and you have still the offset, your coulter is not centered. This can be fixed in tool settings.
You started without bno and mma on mostly flat land, I hope.
The problem was with WAS. Zero wasn’t well calibrated and i had to do a change in line 527:
From 1533 to 1650 in order to set WAS 0 in a correct place. Now everything works very good, the accuracy is around 5 cm and I’m going to use AgOpenGps to seed dry beans.
Thanks you very much for your help
Could an offset happen in V4 that wasn’t there in v3.9? I am using the exact same settings in 4 as 3.9 and I now have an offset to the right of probably 100mm to 150mm. Visible on screen and on the ground.
Very good video. Makes it easy to understand! Not sure why I have the offset but I’ll experiment today. Daren’t try 4.2 today. Yesterday it had communication issues with it. No RTK and other reakky odd stuff going on. My settings obviously but no timey to sort it out till tonight possibly.