The goal is the center of the implement. The linecis drawn ceter of the tractor. It is offset to put the implement on the real line.
Make an abline using the form. Make it somewhere away from you. Make it with no offset. After it is made, get on one of the lines and start autosteer. Once steering well and following the line stop the tractor. Now go set an offset of half your tool width. When you toggle autosteer the line will jump over putting your implement in line with where it was, and your tractor far enough over to drag the implement there. Now do a uturn and you can see it.
Hope this makes sense. The tool guidance is a separate feature being tested. It guides both tractor and implement. The implement has to have some sort of steering. There are basically two lines. A fixed system can’t follow two lines. One has to win. An adjustable ( tool steering) can follow two lines, until you are out of capacity.
I got PANDA to work last night, it felt like winning. Have not had a ride on any branded system that drives like that. Its much better on the small mower, so will be overkill for grain farming.
I did my potato planting and ridging with panda this year. It drives very nice but with heavy hitch mounted implements that couse draft there is still a few cm error sometimes. (has nothing to do with panda, that eliminates the steering wheel to go crazy on bumps and that works really nice!)
I am running it between 5 and 10 mph. typical planting and working speeds.
I mean I have had it running at 45mph but I don’t expect it to perform well at that speed. However it seems to make little difference.
I have parts ordered to get a real life system going. I will do some testing with it. I am sure it will be more than adequate just questions as I am starting with the system.
That’s my biggest issue with the small tractor, AOG is trying to correct but the front end gets light. Or on side hill the implement wants to start steering.
But it is way more stable on Panda, now if it wiggles its due to low DOP only.
I’ve been looking at keeping the implement closer on a contour line. Maybe this has been covered… I would argue that AOG knows very accurately where the implement is (it’s mapping coverage with it), and therefore the error to the contour line. I dont doubt that the code and stability may be vastly different. I guess my point is to ask why we need GPS on the implement to know where it is. Im ok with the theoretical geometric calculation accuracy.
I have in my mind somewhere that Topcon has an option to put tractor or implement as guide point.
The GPS on the tractor can only guide and correct the tractor, if the trailing implement follows the tractor as bonus it all looks very straight. This is how almost all guidance systems work. This is also how the mapping of the implement is done modelling the hitch measurements and type in relation to the tractors gps position. The guidance does not really know exactly where the implement is, its just a really good geometric model based guesser.
For implement control you need to measure the implement position by itself, which means a second receiver. If the implement is not fixed 3pt to the tractor, the implement can be influenced by side draft forces, rocks, side hills and ruts into any random position. Also you would need some means of steering on a trailed implement for it to correct itself if it was offline. Or some tricky code to let the rear gps position, influence the front gps position and over correct the tractor.
Its impossible to control or guess the exact position of a random process, that is the reason for the second implement receiver.
*** in my previous comment I mean the weight of the implement is too great with gravity, and it “steers” or pendulums the tractors rear towards the bottom of the slope… not by choice. There is no GPS fix for this condition.
I’m not aware of any Topcon screen allowing the implement as the steering control point (but I’m not familiar with many Topcon screens). Fendt however has had that feature since the times they used the Topcon AGI-4 receiver (Fendt variant). Later on they added a setting to allow either the tractor or the implement being the control point.
What you are asking appears to be possible but probably not easy to reach accurate following of the wayline and steer stability. A receiver on the implement gives an exact position also when the predicted implement path fails because of unpredictable drift from soil variations or the slope of the field. I understand a second the second receiver would let the tractor guidance work as today except with an integral type of an offset added under the implement receiver control.
What sort of real life scenario are you actually after? Often it is enough to reach 100% coverage even if the implement does not follow the wayline. An example scenario I’ve seen would be a trailed seeder using tramlines but a mounted sprayer where the true tramlines do not follow the wayline on curves. Still almost perfect sprayer coverage but the sprayer runs at times a bit off tramlines.
We have older Raven system that can handle the seeder in the middle of line. Distance from rear axle to the seeding units is about 5-6m.
Our best real life example is field that is shaped like boomerang. Only sensible way to seed is running the long edge and make curved AB-line.
Raven drives over at the outside corner to keep the implement in line. Even that system without RTK goes quite nicely and makes really good results even the radius keeps changing pass by pass.
An angle sensor would give you an idea of how its tracking for sure, very hard to implement on the articulating hitch. But still would not be as accurate and easy as just knowing the position with gps.
Having a fixed 3pt implement is very different from trailed, or trained implements like an air seeder cart ahead of its drill.
Like everything you need to ask how much accuracy do you really need. Seeding on a 40’ seeder with 4” overlap on flat ground does not require implement guidance. Planting onions on a side hill at slow speed probably would benefit greatly from it.
Not really. AOG is only roughly estimating where the implement is. I’m not sure anyone has actually measured how it compares to real life. Under idea conditions it might be close.
For a simple approximation, it does rather well. I think I posted a long time ago with a description of how the algorithm works. My hunch is it tracks a little tighter (closer in on a turn) than the real thing does.
Definitely it does not take into account any kind of side slip, or if the implement doesn’t pull straight.
But why does the implement need to follow the wayline closely on a curve in your case? It does about the same distance on the next path and then coverage is almost perfect. Just record the contour path when you drive the first pass taking into account how the implement drives on curves.
Even if I mentioned an example where it makes a difference if the implement follows the wayline, I’d say most often for single receiver systems it does not matter if it is the implement or the tractor following the wayline. Any more examples where it is important?
Now if the implement needs to follow the wayline accurately, I’d accept a second receiver approach if it makes the SW any simpler. Our RTK receivers anyway are so cheap.
Using an 8m cameleon rowseeder (25 cm pr row of barley or beans)
It is towed so obviously at sidehill it wil be maybe 15 cm beside tractor track, not a problem in distance between tracks as sidedraft is almost same track to track.
Problem occur when you go cultivating between rows( same cameleon which has camera side adjustment (+÷ 15 cm) of frame, to stay correct between rows.
But on sidehill tractor must go uphill and step on rows to keep the dragged machine enough uphill to be able to stay at correct position between rows.
If machine had been steered by another GPS antenna, then machine could have made rows at correct line , and also steer machine uphill when cultivating.
You can even buy a cameleon with hydraulic steering of carrying wheels, and if you have a sbg autosteer system with dual line two antenna steering, you are good to go
I see raven has now taken over sbg.
This is a very valid scenario for the implement antenna option. But I thought the discussion in this thread was about AOG (or any other auto-steer system) with a single antenna on the tractor but estimating the implement path and trying to drive the tractor to keep the implement on the wayline, not the tractor. This approach cannot compensate sidehill drift for the implement.
