[Nathan] needed an autonomous mower to help on the farm, so he built his own without breaking the bank. It might not be the prettiest machine, but it’s been keeping his roads, fences and yard clear for over a year. In the video after the break, he gives a detailed breakdown of its build and function.
It’s built around a around a simple angle-iron frame with a normal internal combustion push mower at it’s core. 18″ bicycle-type wheels are mounted at each corner, each side driven by an e-bike motors via long bicycle chains. Nathan had to add some guards around his wheel sprockets to prevent the chains slipping of due to debris.
Al the electronics and the battery is simply mounted on top of the frame, away from the motors to avoid magnetic interference with the compass. The brain of the system is a Pixhawk autopilot with a GPS module running ArduPilot, a staple for most of the autonomous rovers, boats and aircraft we’ve seen. The control station is just a Windows laptop running Mission Planner, with a 900 MHz radio link for comms with the mower. [Nathan] also gives a overview of how he uses a spreadsheet to set up waypoints.
This lawnmower’s straightforward design and use of easy-to-find components make it an excellent source of inspiration for anyone looking to build their own functional machine.
All wheel drive, tank steer, and quite a long wheelbase!
I can’t help but think that it’d turn smoother with an actual steering rack (or two wheel tank steer and some casters)
Two wheel tank with casters is what I’m thinking. A steering rack adds a lot of mechanical complexity.
But then there’s the traction concern
Front load the weight a bit more until it nears tippy but has reserve, stick a single caster on a tail out back. More of the weight on 2 wheels with little on 3rd probably better than spreading it between 4. Plus you remove the maintenance nightmare of the low bit of chain and can maybe put a guard around it with it just going to the front wheels.
Warehouse robot design w/direct drive pneumatics and casters would have worked better. Come to think of isn’t that what most sitting lawnmowers are setup (2wd+casters)
In the riding lawn mower industry they call that zero turn.
I sounds like later on in the video the audio is dropped out for a period of time
Impressive.
Definitely a hack!!
It’s awesome.
I’d just like to know where people are finding a surplus of cheap e-bike motors…
Bike racks? :-)
Jewels like this are why HaD needs emoticon buttons for comments
https://www.tiktok.com/@tresvogt/video/7108061904614067498
This is what immediately came to mind when I saw the headline…
Ha! This just popped up in my news feed, I’m Nathan. Good summary Danie.
I’ve actually just posted a new video about (in my opinion) an even cooler robot for the farm:
https://www.youtube.com/watch?v=uVJXskpkuEE
It’s a robot running TensorFlow to do image classification of weeds, and it then uses a big fresnel lens to burn the weed to death by focusing the power of the sun on it.
One of the uBlox RTK systems would be a really good idea for this thing.
I missed that he’s using the Here3+ system witch is a uBlox RTK.
A really useful second piece of gear for this would be a Trimble GeoXH – the 2005 models are only a few hundred bucks on eBay, and then you’ve got centimeter accuracy to be able to lay out a waypoint path, instead of relying on wildly inaccurately geo-located satellite images.
To be fair, you’d have to physically walk the device along the path once, but that would be a lot easier than trial and error-ing your mowed areas.
If you see how much semi powdered and shredded organic gunk gets stuck to the outside of a mower you use regularly, I don’t fancy the chain maintenance, be continually washing and regreasing them.
We all can find things that need improvement etc.. but in all due respect this guy has it together as to try to build something himself . My hat is off to this guy lots of good thinking . God bless this guy.