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The Open Mower project allows you to build your own smart lawn mower robot using the Raspberry Pi and an Arduino. The robot is able to localize itself using very precise RTK GPS. As base for this project, an off-the-shelf robot mower is used. The electric components and the software are published as an open source project.

This robot lawn mower is able to record a map of your lawn and mow it automatically. All path planning and navigation is done on the robot mower directly.

If you want to build your own GPS robotic lawn mower, you can get the hardware and software on GitHub. But since this is an expensive project, I recommend to ask your questions in my Discord before you start building your own robotic lawn mower.

https://github.com/ClemensElflein/OpenMower https://www.youtube.com/watch?v=BSF04i3zNGw

⬐ cameronhowe

Post needs to have the title updated. Even though it is called OpenMower it is not open source, it uses the CC-BY-NC-SA license. The readme of the project has been updated to remove the claim that it is.

Of course a person is allowed to license their software however they like. However, I might also note that creative commons is not recommended as a license for code: https://creativecommons.org/faq/#can-i-apply-a-creative-comm....

⬐ jansan

I would say it is open source, but not "Open Source Initiative approved" open source.

⬐ Element_

Another open source robot mower with community following: https://www.ardumower.de/en/home.html

⬐ shimonabi

I'm currenlty building the (mostly) 3D printed one from this website: https://repalmakershop.com/

⬐ daenney

https://github.com/ClemensElflein/OpenMower for the code.

⬐ ratsforhorses

I found this in my archives http://www.ecomowtech.com/hardware.html it's probably 8 years old, lovely idea, wonder if they ever did something with it... tangentially maybe microbial batteries could one day become efficient enough or be used in places where slow is ok https://en.m.wikipedia.org/wiki/Microbial_fuel_cell

⬐ berkes

Looks very much Fi in SciFi to me.

Not saying that it cannot work, but this has so much hurdles to overcome before being something that can work, let alone be produced (at home) or mass-produced and sold, that its at most "really interesting".

⬐ Mountain_Skies

That's a pretty neat project that has the potential to get a lot of interest. I haven't looked at robotic mowers very deeply; currently I use an electric plug-in mower, which is about as non-automated as you can get. But I'm wonder if there are any that support changing the deck height for different areas of the yard. From a software POV, this seems doable but is there any hardware out there that supports this feature without requiring manual intervention?

⬐ dicknuckle

Kind of off topic but I'm currently working on a DIY project to add self-propel to a 110v corded mower.

The goal is to have an electric rope mower for the biggest part of my back yard that happens to have a 110v outlet in the very center (septic alarm pedestal).

https://youtu.be/dmCQkosIa2k

⬐ bombcar

I've never seen a mower with an automatic deck height adjustment, most require you to move a lever on the wheels to change the deck height.

Maybe a full size riding mower would have something automated there? So you'd turn that into a robotic one?

⬐ sokoloff

A worm gear driven by a DC motor with an end stop to “home” at max height wouldn’t be overly complex (and likely cheaper/more reliable than a stepper motor and screw thread as the worm gear can’t be back-driven, so you can power it down and it will hold position to well beyond the tolerances needed for mowing).

If you just wanted to switch between a small number of pre-set heights (and changing those heights could be manual), a cam arrangement is probably better.

⬐ bri3d

Using slic3r as the coverage planner for mowing is an extremely cool and clever idea.

⬐ ragebol

I'd like gyroid infill for my lawn, would look cool perhaps :-)

⬐ londons_explore

When you delve into the source code of 3d printer slicers, you realise the actual smart work really is done inside polygon libraries. Ie. 'take this polygon and inset it by 1mm, returning the smaller polygon and the old perimeter'.

Using that primitive, you can make a lawn mower.

⬐ spacemanmatt

I was impressed to see a decent traveling salesman estimate algorithm in my last romp through a slicer's source code.

⬐ snshn

Now add third axis to it (height of the cut), and make it plot 2.5-dimensional shapes on your lawn to make life interesting for your cat and make neighbors jealous.

⬐ mdaniel

> The border outline is programmed via a standard XBox controller

wow, that's awesome (I mean, the whole project is awesome, but that's an especially user friendly touch)

⬐ H1Supreme

How does this do on hills? This video shows a small, flat yard. Mine is many times this size, and has lots of elevation changes. I looked into robot mowers a few years ago, but I still would have had to mow at least 30% of my yard by hand because of the steeper parts (that really aren't that steep).

⬐ karmicthreat

I worked in this space for a while. It’s a hard problem because none of the mowers take topology into account. Mostly they try to navigate a planned path along a 2d plane and just compensate to stay on their path. So the mower will attack elevation changes wrong.

⬐ voakbasda

Even if you managed to get it to plan a smarter path, steep terrain usually requires bigger motors, aggressive tires, all-wheel drive, and better suspension. Even my big riding mower becomes useless on a hillsides or small depressions when even the slightest dew or rain slicks up the grass, and I still manage to get it stuck occasionally on the dry days.

⬐ ZeroGravitas

I've seen workers operate mowers on hillsides via ropes from the top.

The idea of a little robot mower "mountain climbing" by hooking a spike into the ground and using a pulley amuses me.

⬐ catmanjan

RTK GPS is still too expensive for this to be affordable

I think a sickle style mower is the future of electric mowers as they use less energy per blade of grass cut

⬐ denimnerd42

what's affordable? You can buy corrections and a $300 GNSS receiver or buy two $300 GNSS receivers. That's not too bad for something like a robot mower.

⬐ patrickk

RTK DIY kits for precision-steering tractors are another amazing application of the technology: https://youtu.be/Kwxpo04AC5Q

⬐ fest

Agreed on RTK cost. Two RTK receivers cost about the same as a commercial robot lawn mower.

I have half-finished contraption on my garage desk, consisting of hoverboard electronics and motors (cheapest battery, motor, power electronics combo), PX4 autopilot and a spinning disc with Husqvarna razorblades as cutter. Time will tell if I muster enough energy to deal with the rest of the plan this summer- Raspberry Pi running ROS and Kinect for SLAM.

Right now though, it's just a scary RC vehicle capable of doing wheelies (hoverboard motors have a lot of torque).

⬐ aaron695

None

⬐ wcchandler

This was a pitch of mine. Replace traditional lawn care with automated solutions. I would’ve distributed this to ~6 mowers. That was the easy part.

The hard part was making it look nice. The people that pay high prices for lawn care want it to look it a certain way. I couldn’t get over that hurdle.

I could but it would’ve been me driving over the already cut grass with specific grooming tools, and effectively negating any benefits of me over traditional labor.

I really think this tech is the future, and I’m glad there’s FOSS solutions to get hobbyists 90% of the way. The last 10% is going to be the real struggle for a startup.

⬐ krasin

Good insight, thank you for sharing it. It didn't occur to me after I watched the OpenMower video.

A very small nitpick: OpenMower is not FOSS as it's restrictively licensed prohibiting commercial use (https://github.com/ClemensElflein/OpenMower/blob/main/LICENS...).

⬐ bipson

I don't understand this comment.

Autonomous lawn mowers are everywhere in my neighborhood, albeit being quite expensive. Some even have two for front and back.

Unless you have a very big yard or a very small yard it is quite literally "the thing to have" right now.

This is a huge market in central Europe.

⬐ londons_explore

Why not simply build the roller into the mower?

Then use an algorithm to get the stripes in the right places.

⬐ rambojazz

I really don't understand why people care so much about look when they can have a freaking robot mowing their lawn. It's like complaining that a washing machine doesn't look nice, therefore I would not buy one. The market is so strange.

⬐ sgt

I have a gardener, and I can tell you that the mowing itself is the trivial bit. It's maybe 10% of lawn and garden work. If you want to automate the rest, it's not going to be possible unless we have something like the Tesla Bot.

⬐ spacemanmatt

You're not wrong, but there is definitely a niche for areas with much higher ratio of mowing to gardening work.

⬐ voakbasda

Wrong market. Make a model for farmers and rural citizens that don't care about the look of a rough cut. We just need to cut down a lot of grass regularly to prevent those areas from becoming a breeding ground for insects and rodents.

Then use your revenues to iterate on a version for people that want a lawn that looks like plastic.

⬐ blorenz

I'm the target demographic here. I have 5 acres of mostly non-wooded property. I just need it cut and don't care for striping or any of that. I was mowing with a zero turn with 48" deck. Last year we upgraded to a much bigger deck and the old 0turn sits idle. I wanted to tinker with it and do something similar to this to at least mow the "back 40" where there isn't much to navigate around.

⬐ GLGirty

Have you considered a low maintenance cover crop like no-mow grass or clover? They look like a good idea on paper, but are there side effects that are more trouble than the work of 'modern' lawn care?

⬐ voakbasda

All of my grass is native, not a cultivated lawn. I also have a lot of acreage, and a cover crop would be prohibitively expensive to prep and seed.

Even if you can establish a perennial crop, the native grass can still creep back in and outcompete it. And if it can keep the grass down, the cover crop necessarily will grow enough to create the aforementioned problems with pests. You still gotta mow it periodically to keep everything under control.

⬐ mathgladiator

Bingo, when I had two acres, I would have installed a shed for the thing to home in on and then let it run every other day. I had lots of problems with some weeds which if were nipped in the bud early, then I'd have a nice yard.

The only downside is that I'd need decent monitoring to alert me that I need to intervene before a serious mow is needed.