If you’re lucky enough to find yourself in a position where you can afford a house, you’ll soon find yourself in the unlucky position of having a yard full of grass and weeds demanding constant maintenance. To simplify the task of keeping their lawn from turning into a jungle, one YouTuber went full supervillain and created a high-powered, grass-cutting laser.
There are other ways to automate lawn maintenance, such as letting a robot do all the hard work, but robotic mowers require quite a bit more supervision than robotic vacuums do. Robo-mowers aren’t designed to handle lawns with weeks of growth; they instead mow a lawn more frequently so every pass is a light trim. That requires homeowners to be constantly vigilant about keeping lawns free of debris, tools, or even toys. If a robovac accidentally sucks up a Lego brick, it’s easy to retrieve. If a robomower accidentally runs over a hose, it leaves behind an irreparable shredded mess.
Is attaching a high-powered 40W blue laser from a CNC cutting machine (that’s about 8,000X more powerful than a green laser pointer) to a motorized gimbal and then narrowing its beam with an old camera lens an easier alternative to a robomower? Probably not, to be honest. Is it safer? Most definitely not. But it does look much cooler, with the beam slowly swinging back and forth scorching plant life and anything else that happens to end up in its path.
“Don’t try this at home” should go without saying here, but we’ll say it anyways: this is probably a hack that should have never been filmed and shared with the world, or even attempted, in the first place. But it’s interesting to see the challenges that arose as it was tested and gradually improved.
To keep the neighbors safe, the laser mower was tested against a slight hill so the beam always ended up pointed into the raised ground ahead of it. The laser is powerful enough to actually slice through blades of grass and weeds, but a lot of the time, it simply weakens the plants, which topple over at the point of scorching. That slowly diminishes the effectiveness of the laser, and its reach, as sliced and fallen plant life build up in its path.
Further narrowing the beam and replacing a single laser diode with an array of 24 smaller diodes did improve its performance, but performance is a generous term for a mower that can only cut a small six to eight foot long swath of grass in a week’s time. The maker did upgrade the laser emitter by mounting it to an automated RC vehicle that could slowly creep forward over time to improve the laser’s ability to cut down plant life, but with a top speed of about two meters per day, it’s still an agonizingly slow way to handle and automate lawn maintenance.
That’s not the point, thought. The point, as Old Ben once taught us, is to cut in the most civilized way possible.