Been looking through CYouturn.cs but at over 1800 lines its a bit daunting.
At the moment youturn only draws in the direction towards the next AB line, if the turn cannot be completed without going out of bounds the youturn is moved until it can,(great feature to stop machine getting caught in corner) trouble is this leaves a section of AB uncovered requiring more headland passes.

If possible I would like dubins to use an opposite turn at end of row if normal shortest path not possible due to boundary. ( I think this is already calculated in code but not used) This would allow current AB to be completed. Then machine to loop around (ie 300 degree right turn to head left) and follow the boundary until next AB is encountered. Only if there is no Dubins solution at end of row should the youturn start pos be moved to stop machine being caught up in boundary

You Turn is surprisingly difficult. I’ve thought about what you wrote about, but to do it in software is another story. There are so many edge cases on how to do those kinds of turns - easy for us to look and say go left, drive around, follow a path, go back, but there are literally millions of combos where they are all slightly different. For now it is beyond me how it could even be done.

If you are willing to try, that would be great. I can help out if you get stuck on how existing code works.

Would it be possible that if a uturn is not found within so many meters of the u turn line then it stops checking and the tractor is allowed to make the majority of the last abline before it shuts off? (Say to that point) I could see this to be a problem if the field had a large step in the boundary. It would need user input to keep from getting stuck in the corner anyway. But just wondering.

Thats what happens now, when uturn advances too much and leaves a long portion of current AB undone, driver turns uturn off, manually turns then switches it back on on the next run.
I do believe we have found, and are working on a solution, @BrianTee_Admin could probably code it in no time, but we will try first.
we got youturn to draw the second shortest dubins path ok, but when AOG drove it, it got stuck in a loop, so not really practical atm.

Been working on Youturn, very early sneek peek, lots of code to finish & bugs to fix. had to get turns accurately following Youturn line first.
Insipired by @BrianTee_Admin and coded by my son Travis. My input is just ideas & keeping the supply of refreshments flowing.


Awesome !!! That is just what I need on my sprayer !! Nice work .

Definitely a great enhancement!!!

Gonna be tricky at the beginning / end of uturn and making sure it can actually make the turn. But i think the challenges of that pales in comparison to just following the uturn line advantages. Still gonna be in the tractor to cancel if required, not autonomous requirement.

Great job.
Would you not end up with missed passes if the program just picks route according to the turn?

Yeah. Youturn radius needs to be bigger than min turn radius so tractor has enough reserve turn to follow line. Will need another setting for this in setup form or we can fudge it by making youturn radius 10% bigger than min turn in code.

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Finally got Travis to post AOG with his enhanced Uturn code to his Github page.
Would really appreciate if anyone interested, could build it, check it out and give any advice/comments.
Must set steer to pure pursuit, stanley code still not fixed.

Once i get v4 posted, I’ll try to figure out what has been done. Really excited to see that work

Weeks of work and math that’s way beyond me, squeezed into a few minutes. Thanks go to my son Travis for persevering with this. At times it really did seem an impossible task.


Wow, great work Travis and Andrew!

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Not many edge cases left! That works very well. Such an awesome addition. Great work - I see this program is just as addictive on the other side of the world… Good thing.

Frigging addictive alright, having trouble getting Travis to do normal farm work!! When that video was made we thought we nearly had it done, a few seemingly little tiny bugs that would have annoyed everyone has caused a rethink and pretty well a complete rewrite of his previous code.
That bloody saying 90% done 90% to go, rings so true.
For those waiting that may use this feature we apologise for the wait but hopefully its done before the silly season sets in.


Cool! I find it amazing how close you can get to like 98% and then go shit, really, damn. Hopefully we can jam it into v4.1

Hi ,
Does anyone have to continue working on these functions? The trials were promising.
I tried to access travis’s github (@APM) but 404 error … I should have saved it the last time I took a look. I have now evolved a little in the understanding of C so I would have liked to take a new look.

Hmmm. It was functional but put on hold as we got busy and my test tractor hit by lightning last Feb, and still not returned as dealer found not a simple fix as first thought.
Code is still available. Will see if I can get Travis to post it so you can test.

@Tooki57, I edited the link in post 9 to travis’s github. he had changed the name on me!
the code for the uturns is split into 26 commits with pretty good descriptions of what is going on to make it work. let us know how you get on with it.

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Hi, are you talking about fixing this problem ? Uturn doesn’t go on headland track.