I'm getting tired of being swarmed by bugs every time I have to mow which in peak season is every three days. I'd much rather sit in my air conditioned office and control the thing with a gamepad. I don't think the robot mowers are capable of handling anything more than a suburban lawn with those teeny tiny razor blades they use. It actually seems like it would be an easy project. I need: - One servo on each hydro - A camera - A way to trigger the parking brake (might be a bit tricky as my cub cadet does this when you rest the lapbars) - Control software (this is actually the easy part for me as I have a background in software engineering) Can use wifi for connectivity. I'd setup an AP specifically for mowing purposes to get the range needed. Actually, can do multiple APs, as long as they use the same SSID the thing can roam. Anyone done this? It seems almost simple. Just need servos that have the right torque to manhandle the hydros and everything else seems like a freshman-level engineering project.
This is an interesting challenge. there seem to be folks all over youtube showing off their conversions, so it's clear this is a relatively easy project, but at the same time I can't find any actual documentation online with actual writeups so I'm flying a bit blind. Probably need to find a spec sheet for the hydros in my mower and see what the range of travel is and how many torques are needed to move them--something that if not available I might have to wing it a bit. I did see where a lot of folks are using windshield wiper motors as servos so that's probably a good starting point. Reminds me of a project I did a while back at work. We had a supply closet that looked sorta like an elevator with double doors and it turned into a bit of a meme. At one point we rigged up a windshield wiper motor onto an old timey elevator brass floor display pointer thinggy and added call buttons. Using a raspberry pi I rigged it up to trigger the floor indicator to move and had the thing play stereotypical elevator music.
Very rough numbers but I just replaced a commercial hydro motor on my Exmark. I would say the control arm rotates 15-20 degrees (more forward and less in reverse) and requires roughly 3-5 foot pounds of force to go from full forward to full reverse. Big difference between hydraulic and hydrostatic motors.
I've done a lot of tinkering on a wood chipper that uses a ZT hydro and I would guestimate 15-20 ft/lbs. I'm sure it varies depending on the unit. I wonder what's easier to use; a linear actuator, or a rotary servo. The control force going into the hydro is obviously circular but at least on my chipper there is an offset arm that sticks out, and the control cable is purely linear action... Guess it depends on what I can find at what price. I'm not in love with the wiper motor idea and would prefer to use a proper servo or actuator, mostly for ease of interfacing with the computational side.
New idea--and I actually think this will be the item that really makes this project happen--I have a weekly chore every monday morning that I hate. I have to take my dumpster down to the curb. The curb is half a mile away. I've got a cansporter that goes on the back of my truck that makes the chore pretty easy, but it's still a chore. If I put a cell modem on this thing, the only thing stopping me from being able to remotely deliver my trash can is going to be a lift actuator on the cansporter. This is almost as good of a QoL upgrade as a remote controlled mower. It also removes wifi from the equation so I don't need to worry about range. And I don't even need to worry about pickup--that's non-time-sensitive and I can do it whenever I get around to it.
