Inputting Custom or Pre-recorded paths

TLDR: Is there a way to enter in custom or recorded tractor paths?

I am having trouble within the simulator (v4.3.0) with the paths generated by the boundary contours. They will go from a ‘good-looking’ path to one that doesn’t hold the line and often crosses itself. Is there a way to by pass the auto-generation and feed in concentric, pre-defined paths to create the headlands?

BACKSTORY: Hello, I am new to the forum and new to AgOpenGPS (AOG), however I have been a long time lurker. My father-in-law is a farmer and works in an area where labor is hard to find and adding autosteering to his equipment will help him offset the lack of labor with increased efficiency and accuracy. He has no autosteering functionality in any of his equipment, citing cost. I am trying to get him over that hurdle with an AOG setup.

The problem is that many of his fields have sharp, acute angle outer borders and waterways too deep to traverse. While simulating the headland planting, the paths have the above described behavior. My thought was to pre-fit paths in concentric inward steps from the outer border in another program (likely python code) and send those to AOG to plant the headlands.

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Custom progaming, but it will. I built a draw recorded path, and also an import path from Google Earth. All you need to do is write a recorded path txt document. A few problems that I ran into is in the sharp turns. If the tractor can’t make the turn, randomly it will drive off at a tangent. Not every time, randomly. If you get one turn figured out then you’ve busted another turn. You must import the path with the turns the tractor can make and inside of the parameters of AOG. As Brian has said, it was built around larger machines, 10 meter wide. It will do less, but after a point it will start “driving through the holes” in the path.

  1. Can you point me to some resources on the txt creation, formatting and file name?
  2. Can I tune the parameters of AOG to minimize these path finding errors?

Mainly, which file should I write the recorded path to and what is the formatting of that file? It looks like the is at least a header section with a couple of lines followed by a series of 3 comma separated values in the main body.

My plan was to use python to create concentric paths with the machine constraints built in, with the minimum turn radius, width, etc defining those paths. As far as parameter tuning goes, I am at an early phase in the deployment process and I am using the default v4.3.0 tractor and equipment settings. Can the AOG be tuned further with these parameter (and future real equipment specs)?

Thank you for your reply! My apologies for not leading with that, I do appreciate any and all assistance!

The best thing to do is to build a GPS point list outside of AOG. Then use the internal converters to convert these points to easting and nothing.

The recorded path file is simply a text file with a header (which is ignored), a number of points, then comma separated text.
easting, northing, heading, speed, true or false if tool is on.

I used the built in reader and writer (opensave) to read and write what text I needed. It is a bit daunting when first looking at it. But, it works very well. This is the image of what it did.

You can find it in this thread. It will give you some good file reader information that you will need.
[Convert AB-lines from Trimble to AgOpenGPS]
(Convert AB-lines from Trimble to AgOpenGPS)


To answer your question about tractor settings. Only to a point in the default AOG. However, the best thing about AOG, is that @BrianTee_Admin made it truly open source. That is, you can change anything. I’ve had mine so out of working condition that I had to delete the entire folder and download a new copy and start over many times. I learn best by making mistakes. Make small changes and run it to see what you did or did wrong. What you will find in the path errors is that AOG was not designed to drive to a point over either of your shoulders. If the tractor can’t see the line, it can’t drive to it. And some times it has a pretty narrow vision. Good Luck. It is bad addictive. Post back with any success.


I have noticed AOG program (when in Pure Persuit) does narrower left turns, than right turns, before taking off.
It happens in the middle of the turn , so I think the mathematics can´t switch to the next A B line.
That does not happen on left turns, there it always stay left.
Watch the Steer Chart during turns going slowly, it is more uneven doing right turns.
In PP and SIM mine will do left at radius 120 cm (maybe below) but right not under 175 cm. radius.
Stanley works both ways with 120 cm.

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It has a lot to do with the atan function. I never got to the bottom of it. but when we built the MICROGPS, it really helped. AOG was built with a 1 meter or so step in the U-turn points. If using a vehicle with a tight turning radius, it will miss these. You are correct that it will turn tighter one direction than the other. But just the time you get it figured out, you drive in a different angle and it will, as we say down here, “go off to Jones’s”. It set’s the steer angle to zero and the U-turn does not ever complete.

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