MOWSTOCK – 2023, April 21st and 22nd

Mower/Rover Folks!

We are having a “gathering” here on the farm for anyone interested in learning/building autonomous Mowers/Rovers/Boats/Drones, etc. The main goals being to meet, compared ideas/best practices and share experiences with putting these things together.

We should have at least 5 working mower examples on hand and everyone is encouraged to bring their own. We have ~100 acres of short hay fields to play with so room to roam is not an issue. Will also have our on-site RTK (via NTRIP) active and available for use.

Several folks from the Ardupilot Forums and YouTube fame will attend including Yuri Rage (Yuri’s Homebrew & DIY - YouTube) and Kenny Trussel (Kenny Trussell - YouTube).

Church Point is a small town about 20 miles NW of Lafayette, LA with no motels. However, Lafayette is a large metropolitan area about 30 minutes away with many motels and a large, full service airport served by American, Delta and United. RV’s are welcome but please call for details.

If attending, please contact so we can plan accordingly!

Location Address – 1529 Beaugh St, Church Point, LA 70525
Contact: Steve Webre – 337-349-8365 or “”



Steve, Thanks for hosting this event. I can’t wait!

Should be a good time!

I’ll bring every operable robot I can find.

We can collectively beat our skulls against the wall in forcing the new nav controller to bend to our wills.

Sorry to miss it! Look forward to seeing what everyone learns…


I’m looking forward to playing with Scurves. I have my Version 2 mower ready to roll out of the shop, likely tomorrow. I have the latest beta on it, but if I don’t get relatively straight lines pretty quickly, I’ll shift back to NAV L1 to get some work done and save the playing for Mowstock.

I’ll be bringing my Hogbot (built by Yuri), my mower (built by Steve, Bill, Yuri, and me), my drone, maybe a new RC plane still in the box, and maybe a surprise.

Gonna be fun and highly educational!

Sorry you will miss it, Chris. It would be great to shake your hand and maybe see your machine! There will be other opportunities, I’m sure, though.

We are operating 3 mowers simultaneously:

Google Photos


Looks good! Run time between charges?

4-8 depending on grass condition

The first day of “Mowstock-2023” is in the books! There are currently 6 ArduRover-controlled mowers in attendance:

(That’s @SJohnson from Texas in the view.)
More fun, trading tips, and helping each other continues tomorrow.
Thanks, @Swebre and Mel for hosting us!


I just wanted the express my appreciation to Steve Webre @Swebre for hosting this great event and I wanted to thank @ktrussell and all the others that helped me to learn more about the mowers and the details of using the Ardupilot software. It was also a great opportunity to meet the real people behind the names and faces we see on the internet.

Here is some information on a few parts that a few people ask about on my mower.

Here is the little sealed more industrial DC-DC converter that was ask about.

MowStock was great event!
Thanks again to Steve Webre and Mel

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Want to “Thank” all involved in MowStock gathering!

Several folks drove a long way and in the end, we had 6 functioning autonomous mowers show up. So for the moment we claimed we had the “Worlds Largest Gathering of DIY Autonomous Mowers”! (Lots of laughs ensued.)

I think we all learned a new thing or two and generally had a great time. The most interesting part for me, besides meeting folks face-to-face, was seeing and discussing the different logical and mechanical approaches we took to the same problems.

Looking forward to the next time we can gather up. Onward!


Congrats to everyone !! Sorry to miss it. Onward and upward!

@ktrussell @Yuri_Rage and others: Recent video with 2 mowers working (for some reason it seems the default viewing resolution is low, and that one must manually select high resolution replay when viewing these videos from google photos):

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Looks nice, Chris. You have a lot of tree cover there. Do you loose RTK often? I have a potential area I may cut that will have a lot of trees. Currently, I’m mostly in the open.

Also, are you using active object avoidance (LiDAR or something similar) or just planning missions around your trees?

I do occasionally lose RTK, and it seems that it happens more under heavier tree cover… and I also have a hypothesis that it happens more when the trees are wet. When the GPS fix level is 4 or less, I pause, and wait, and resume when GPS level is 5 or 6 again. (This logic is implemented in my companion computer, not on the autopilot). I estimate this happens every 10-20 minutes in the most heavily wooded parts of my lawn. Usually the GPS drops to 4 for <5 secs so not a major factor. About once every 10 hours I have a pause that’s more than 5 seconds. I’m sure I will learn more about this as I mow at more properties this season.

Do you know if there’s a difference between GPS fix level 5 and level 6? Right now I’m mowing with either 5 or 6 because I think they both indicate an acceptable level of precision. But I actually don’t know this for certain.

No active avoidance, just mission planning around trees and obstacles. We record a perimeter, and record obstacles, using a mower. Then we use those recorded perimeter and obstacles as inputs to an automatic mission planner that builds the back-and-forth strips and navigates around the obstacles. We used the logic in this whitepaper as a starting point A novel solution with rapid Voronoi-based coverage path planning in irregular environment for robotic mowing systems | SpringerLink

Then of course, before beginning a mission, we visually scan the yard to ensure there are no new obstacles. Which works pretty well but not perfectly. Yesterday a mower met up with this yard waste bin.

GPS level 5 is RTK Float. Level 6 is RTK Fix. I have found that float is pretty bad. I stop if RTK drops below 6. @Yuri_Rage wrote a Lua script that does that. It can easily be tweaked to do what you are doing with your companion computer. A couple of years ago, a companion computer would have been required to do it, but the Lua scripting has enabled a lot of functionality right in the FC.

Thanks for the white paper reference. I am using the built-in Bendy Ruler OA with exclusion fences around trees. Unfortunately, the way it is implemented leaves a triangle after the obstacle. I have to manually insert some waypoints to fix that. It has worked well for me with that modification, however.

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@ktrussell @Yuri_Rage I have been experimenting with the horizontal accuracy reported by the GPS (h_acc in the mavlink message). It seems it may be a finer-grained accuracy indicator than the GPS fix type. The lowest value for h_acc (i.e. most accurate) I see is 14mm. When mowing in the open, it generally varies between 14 and 18mm. Then under heavy trees it can increase up to 50 or 60 mm. What do you think about using the horizontal accuracy (rather than the gps fix type) as the basis for stopping mowing when GPS accuracy falls?

Nothing wrong with that approach. Would need some testing to determine its true validity.

I haven’t had any issues just pausing on anything worse than RTK Fixed.

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