Remote Control Lawnmower

This sounds kind of fun!

Would it surprise you that such a thing is already a thing? This link below is one manufacturer that has many of your desired features:

https://www.robotlawnsmower.com/product/tracked-lawn-mower-remote-control-8-0hp/

This is a complete remote control gasoline lawnmower, not your requested modification to a full sized zero turn machine.

The linked page says nothing about the remote control platform, but the videos show a fellow using a UAV drone sort of controller, but no from-the-mower video; might be an option.

There are many, many hits featuring other manufacturers from an internet search string.

I never doubted that it could be done, and I have seen it also, but I have a commercial mower that needs using a lot. I just want to modify it on the cheap.

I have seen wire guided vehicles and carts following wire in concrete with reed switches as way-points. A wire around the property would be no problem, perhaps in a concentric path following the outline of the property.

I'm still thinkin' on it....

As I said, sounds like an interesting and fun project. If you want it for this season, ya better get busy!

On the cheap? Well, maybe. If it’s something you want, and you enjoy doing it… does out of pocket matter very much?

Good idea. I can see that working for control. Need 4ea electric linear actuators with enough toque to move the valves, Spring return to neutral(Straight ahead).

And of course, the wiper motors might be cheap and available also.

MOSFET's for final high power output drivers an EXCELLENT ANSWER.

I can strip down an old smart vacuum floor cleaner and not have to buy many parts.

A friend of mine disassembles everything into individual components and sorts them. He has just about everything you can imagine. He will pick up an old tv from the curb and strip all of the parts from it. The aluminum screens are recycled. Steel parts are separated for recycling.

He picked up a scrambled top secret transmitter from the dump and disassembled it into parts. The government finally traced it to him and wanted it back. He said "There it is" pointing to the shelves of parts. They jut shook their heads and left. No danger of an enemy state finding that.

Surprisingly, he is not a normal hoarder, his stuff is organized like a library.

I seldom have to buy any components. I build mechanical things for him. He gives me parts and suggestions for applications. .

The world needs more people like him, there would not be as many landfills.

What a great mate to have, I have a shed, several sheds, too many sheds to store my various scavengings, also aa dedicated electronics area just full of small component draws. You are lucky to have such a friend.

All the best.

Rather than get into the hydraulics, a new servo or proportional valve, overkill for your application, I think as Stef recommends, move the controls mechanically with 12V linear actuators, should be half or less the cost and less risky. Those valves are sensitive to hydraulic oil quality, cleanliness.

Radio controllers for model airplanes or a drone controller with throttle and control surface manipulation seems like they should be ideal, even equipped with a remote video feed. Might need amplifiers to handle the electric current required to run the levers, and probably also for throttle and brake. If the actuators are equipped with positioners, then the control signal levels could be compatible.

You would need to measure the force required for each control, and hopefully find existing parts that can produce the effort required.

But the basic operation model is the same, adjust position and speed with visual feedback, so the controls should already be configured.

NO problem figuring out the torque. I have a pull/push force gauge. Wrap a string around the valve lever shaft and look at the gauge.. It is very accurate, I have tested it with weights. Used it for setting up preload on bearings and differentials.

NO problem figuring out the torque. I have a pull/push force gauge. Wrap a string around the valve lever shaft and look at the gauge.. It is very accurate, I have tested it with weights. Used it for setting up preload on bearings and differentials.

No need for speed control, engine is designed for full throttle operation and must have to keep it cool. No brakes required, neutral will stop it and hold.

This is a commercial Grasshopper mower.

Now I am off to the races!!

First up is how big is the area you need to mow ?
How big is your present mower ? Cutting Size.
What do you do with the grass you have cut ? How do you collect it ?
Petrol or Diesel motor? With or without gearbox ?
Speed control ??
Alternative option, less complicated and much cheaper; Wear a Covid type mask, stops Pollen, build a Sunshade like a Golfcart on your Mower keeps you out of the sun and mount a large fan with a tray for Dry Ice which will keep you cool and will offer the opportunity to keep a beer or two cold... Mowing a lawn needs a beer !

I have a friend in Houston, TX that is facing the same dilemma. It's so hot & humid that he doesn't enjoy being outside unless he's in his swimming pool. His solution? Move! He has decided that northern New Mexico will suit his needs better, now he just needs to sell his current house.

I don't think you want such a drastic solution. I also sent my friend links about autonomous lawn mowers, but he didn't go that route. Instead, he bought a riding mower and let his wife do it. Now he realizes that is a short term solution.

I have over an acre that I mow with a 48" commercial mower (Scag). I can mow, collect & dump the cuttings, trim & edge in about 3 hours. I don't mind doing it, finding time is the hard part for me. My wife finally hired a lawn service to come do the mowing for us. It remains to be seen how this works out.

I know you'll enjoy the challenge of building your own, but it sounds like you're re-inventing the wheel. One more thing that you'll need to consider--the mower will need to sense obstacles. Not just stationary trees and such, but things that can move, like children's toys.

With CNC experience it is clear that a tool path is essential to avoid that lawn is skipped and no spot is mowed twice (or and least too many times).

You would need AI to design a tool path and GPS system to execute the tool path correctly.

There are agricultural systems available but it may be an overkill.

I now rather rely on garden services for my small lawn (6000 square ft in 3 pieces)

In the 'old days', we used to call that equipment "neighborhood teenagers". Not sure you could get any of them off their cell phones now. Maybe if you could dress up your yard like Mario Cart, you might be able to entice them onto your mower?

One of my concerns would be the slew rate of the actuator driving your hydraulic control valve. Is the unit going to be fast enough to mimic a human operator? The other issue that comes to mind is and some sort of feedback system. The "seat of the pants" inertial sensing system in our ears is going to be a lot more sensitive than viewing the mower from a distance. That kind of feedback is important to the control of the mower. This is an age-old problem for the operators of remote controlled vehicles.

One of the sub-sea industry specific articles on AI I saw recently and now I cannot find (), was promoting their AI pilot that controlled the vehicle following the desired inputs of the operator. They had chart overlays showing an experienced ROV operator manually piloting the vehicle on a prescribed track. It then showed how the AI-enhanced pilot installed on the same vehicle could follow the prescribed track far more accurately and without the hysteretic deviations of the manually controlled vehicle.

It seems like a remote controlled plane/car servo system should be able to get your commands to the mower. The tricky part is going to be the amplifier to take the servo signal from the controller and apply current to the electrical actuator. The trouble I was running into is that there are many electrical actuators for sale on Amazon for instance, but I could not find any with an integral displacement sensor. The displacement sensor is of course important to create the error signal of your control system.

I have not done much R/C stuff, but it looks like modern PWM controllers may be the way to go. You can get a fairly high current motor controller that looks like it would drive any of these actuators you can buy off of Amazon. This 'amplifier' will drive 15 amps, but only in one direction so you would need two of these with the appropriate blocking diodes to run the actuator in both directions.

https://www.robotshop.com/products/servocity-15a-motor-controller?qd=cd93426cc034a36e73aa209813418b5d

The RobotShop website looks like an interesting place to peruse this sort of thing.

https://www.robotshop.com/collections/wireless-rc-pwm-servo-controllers

I'm in way over my head, so I should probably stop now.

There are hundreds of remote lawnmowers in the Internet that work by remote control, prices range from a few hundred dollars to 13k.
Probably cheaper to sell your existing one and buy a new one already equipped with a remote system.

Here is one example: https://us.mammotion.com/products/luba-3-awd-robot-lawn-mower?variant=50985057288490&utm_source=google&utm_medium=cpc&utm_campaign=mammotion-demandgen&gad_source=2&gad_campaignid=23671684720

You could just buy a couple of sheep.

An enterprising young farmer here was given a small flock of sheep when she was young. She started hiring them out to local businesses as an eco-friendly way to cut their grass. Pop an electric fence around the area, decant a few sheep & they get free food. The workers also got to watch the sheep as they worked.

Bob Widlar thought it was a good idea for National Semiconductor.

https://www.computerhistory.org/revolution/analog-computers/3/156/400

https://www.electronicdesign.com/technologies/analog/article/21795678/whats-all-this-widlar-stuff-anyhow

I remember reading, many years ago, where the government had installed solar powered mowers on large open areas. There were dozens of them, like sheep. They would run till the battery got weak, then stop and recharge and go again.They sensed when the grass was taller than the previous cut, and only cut the amount necessary, usually only a few tenths of an inch .

There was always a bunch or mowers moving like a flock of sheep.The property always looked fresh mowed and the grass never got too tall.

Why not now ,with modern tech and batteries?

Yeah, I remember that.

IIRC, that was the first episode of BattleBots.