You know, I've always been a bit skeptical about those robot lawnmowers. Fancy, expensive, and most of them use those whirly rotary blades that don't give the cleanest cut. I've always preferred the cut from a good old reel mower, but man, pushing one of those things around in the summer heat? No thanks. So, I got this idea stuck in my head: why not build my own reel robot mower? How hard could it be, right?

The Grand Plan (Sort Of)

First off, I needed a reel mower. I wasn't about to go buy a new one just to tear it apart. Luckily, my neighbor had an old, rusty manual reel mower just sitting in his shed, gathering spiders. He was happy to get rid of it. Score! That was the easy part. Then came the 'robot' part. I figured I'd need some motors, wheels, a battery, and some kind of brain. I had a couple of old wheelchair motors lying around from a project that, well, let's just say it didn't quite pan out. Don't ask. Those things are beefy, probably overkill, but hey, free is free.

My initial design was sketched on a napkin. Literally. I thought I’d just bolt the reel mower on top of a frame, hook up the wheelchair motors to some new wheels, and figure out the steering later. For the reel itself, I planned to use a smaller motor to get it spinning. Simple.

Getting My Hands Dirty – The Build

Let me tell you, getting that heavy reel mower assembly to sit nicely on a new frame was a pain. I used some scrap aluminum angle iron I had. Cutting and drilling that stuff in my garage, with basic tools, made a heck of a mess. My wife was thrilled, as you can imagine. After a lot of swearing and misaligned holes, I had something that vaguely resembled a chassis.

Next up, the drive motors. Those wheelchair motors are powerful, but they also draw a lot of juice. I found an old car battery that still held a charge. Heavy, but it would do for testing. Attaching them to the wheels and then to the frame took some doing. I had to fabricate some mounts, and let's just say my welding skills are… artistic. More like abstract art, really.

Then, the reel. I tried a smaller 12V motor I had, but it just wasn't strong enough to spin the blades through even light grass. It would just hum and get hot. So, I had to upgrade to a slightly beefier motor, something from an old electric scooter, I think. Rigging up a belt drive from that motor to the reel cylinder was another adventure. Lots of trial and error with belt tension. Too loose, it slips. Too tight, it strains the motor.

• First attempt: Motor smoked. Oops.
• Second attempt: Belt kept flying off.
• Third attempt: Got it spinning, but wow, was it loud!

"Brain" Surgery and Making it Move

For the brains, I went with what I know: an Arduino Mega and a couple of motor driver boards. I'm no coding genius, so the first goal was just to get it to move forward and turn using a cheap RC transmitter and receiver. That part was actually kind of fun. Seeing it lurch forward for the first time, even if it was completely uncontrolled, was a small victory. It almost ran over my toolbox. Good times.

Steering was tricky. With two independent drive wheels, skid steer was the way to go. But getting it to turn smoothly, instead of jerking around like it was having a seizure, took a lot of fiddling with the code. And I mean a LOT. I had it running in circles in my driveway for a while. The kids found it hilarious.

As for making it 'autonomous'? Ha! That was the dream. I stuck on some cheap ultrasonic sensors for obstacle avoidance. Let's just say their performance was… optimistic. It seemed to think shadows were solid walls, and actual solid walls were occasionally invisible. My garden gnomes were not safe.

The Moment of Truth (and More Mayhem)

Finally, I took it to the lawn. The first "test cut." It was a sight. It moved, it spun its reel, and it did, technically, cut some grass. But it also scalped a few patches, missed others entirely, and got stuck on a slight incline. And the noise! Sounded like a small threshing machine was loose in the yard. My neighbor, the one who gave me the mower, just stood at his fence, shaking his head and grinning. I think he was enjoying the show.

One time, I was testing it near the flower beds. My wife had just planted some new petunias. I thought the sensors would pick them up. Nope. Straight through. Let's just say I was in the doghouse for a bit after that. Had to promise to stick to the open lawn areas after that particular incident.

So, What's the Verdict?

Well, it’s not going to win any design awards, that’s for sure. It’s clunky, loud, and not very smart. It sort of mows a patch of grass if you keep an eye on it. Is it practical? Not really. Was it fun to build? Absolutely. I learned a ton, mostly about what not to do. It’s still sitting in the garage. Every now and then, I tinker with it, thinking maybe I'll add GPS or a better sensor suite. But then I remember the petunias, and I go have a cup of coffee instead.

The thing is, sometimes you just gotta build something, you know? Even if it’s a bit bonkers. It’s the process, the figuring things out, the small wins. That’s what keeps me going. Now, what to build next…?