The Combine Forum banner

Topcon X20 slow locking onto line

9K views 22 replies 9 participants last post by  joeltractor 
#1 ·
My Topcon X20 seems a bit slow to get hold of its line after engaging.

I do the turn, line up as best I can, press engage, then it will drift offline, and take about 200 metres to get itself lined up again.

The steering wheel is just merrily rocking back and forth, while the screen shows it is off to the side of the line, and it doesn't seem interested in getting it lined up.

If you grab the wheel and help it out, you can get it lined up pretty quick, but sometimes you have to do it 3 or 4 times before it sorts itself out and goes nice and straight.

It happens after both right and left turns. If you turn right, it will creep to the left, you have to assist by steering it a little right. If you turn left, it wll creep to the right.

Even if you turn a little tighter than necessary, and press engage, it will drift past where it should be, go off to the other side, before eventually coming back.



It seems worse after a full 180 degree turn. After a small deviation around an obstacle, it gets back to a straight line sooner.



Once it does get lined up, it holds the line pretty well.



It is on a RTK network.

It was purchased second hand.

Wheel angle sensor is fitted and working.

Tractor is a Versatile 9280. Steering pins have a little wear, but not to the stage where I want to replace them.

Settings as set up by a Topcon dealer are:

Approach:
Smoothing 5.0
Lookahead 8
Aggressiveness 110
Approach align 10

Parallel
Smoothing 3.0
Lookahead 10
Aggressiveness 105
Line hold boost 0.5

Any suggestions?

Do I have a problem or is this as good as it gets?

I thought this system would be capable of inter-row sowing, but there is no way I would be able to consider that as it is.
 
See less See more
#3 ·
Thanks for the suggestion, the X30 may be different, as the lowest number it will let me put for the lookahead is 5. So anyway, I set it to 5, and it seems to have improved it a bit. But I still have to grab hold of the steering wheel and help it to get online sometimes. Any other suggestions?
 
#5 ·
It's sure lazy alright. No Topcon autosteer experience here but with Trimble I'd be inclined to increase the line acquisition aggressiveness.

I'm wondering if the machine setup is right. When you say once it has the line it returns more quickly and off of small deviations it makes me think the PID is at the extreme's and it could be due to poor sensor/actuator calibration.
 
#6 · (Edited)
Where is your antenna? Move the antenna to the front of the hood?

Stuff you never asked for but......
The closer your antenna is to your pivot point the slower it will be to react. The farther you are away from your pivot point the more "leverage" you have to calculate how far you are off line. Think of a 2 wheel drive, if you put antenna between the back wheels the tractor will have to steer a long ways before any noticeable change in position is detected. Now if you move that up to above the steering wheels, a small change in steering and position of the front end is quickly and easily detected.

4WD pivot and positioning is complex depending on pivot point, articulating position and antenna position.
 
#7 · (Edited)
To me your lookahead is a bit high in parallel and the smoothing is to high in approach ,this will make it lazy to get on line. In the bottom left hand corner click on advanced i think it is called and enter the code 122133 and you will see a heap more settings under the tuning tab .The main ones are mins ,which on a electric steering wheel should be 3 or less ,valve speed and wheel angle speed. Drop the lookahead down and if you need to play with those three if you need to. Once you are happy with it press update configuration to save the settings. Edit ,looks like you already know how to get into the advanced tab
 
#9 ·
I have the parallel lookahead now down to 5, which is the minimum.

The approach smoothing is down to 2.

MinL and MinR are both at 0.0

It may be slightly better but still not great.

Any ideas about why it recovers better engaging after small deviations than full u-turns?
 
#13 ·
BrianTee - Up until about 2-3 years ago, I completely agreed with your thinking on antenna placement. Had 3 articulate tractors with antenna's mounted ahead of nose and 3' above top of hood line - just was unable to get acceptable performance. Have since moved all 3 to above center of front axle and they are working well. Right or wrong, I now think of antenna's as highly accurate compasses that are updated every few seconds.
 
#18 ·
err, cant help with Topcon, or any settings advice at al . . .


but . . . my Autofarm system developed the SAME symptoms 2 or 3 times
from memory, one time it was an issue with the wheel angle sensor
other times, technician updated / recalibrated ?? something in the monitor


best bet would be to get a service tech sitting in the cab - the call out fee will be cheaper than all the messing around & frustration of it not working & trying to sort it out yourself
 
#19 ·
Thanks for the suggestion. I disabled the wheel angle sensor to see what would happen, it was completely hopeless. So I enabled it again and ran a calibration, no improvement.

I know what you mean about being worth getting a tech to check it out. There are two techs within about 100km of here.

One hasn't got back to me with a quote for a complete new system.

The other set up a repeater for the RTK signal, and was sitting in the tractor, so I mentioned it to him. He said grumble Topcon grumble X20 grumble buy a Trimble. Or something like that.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top