The problem:>my potatoes and veggies get overrun by weeds because I'm not in my summer house often enough to weed themThe idea:>build some kind of ROV that can be operated over the internets that has some basic tools for weeding and maybe other tasks like watering>tall enough to pass over potato plants without harming them>solar powered>as dumb as possibleof the existing solutions I've looked at, the Weedinator looks most similar to what I'm after. but it's built around a tractor which seems excessive for my needs. plus it isn't solar, which means it can only run for so long. it has some good ideas like following ropes on the ground and using barcodes to demarcate thingsoh and an ROV could be useful for other tasks, such as surveillance and scaring away deerideas? hardware sketch follows
my current idea for a platform:>get two "male" mountain bikes, because they have that horizontal "testicle smasher" tube>weld them together at a distance of 2.4 m (the length of a solar panel) using square steel tubing between the nutcracker bars>flip it around so that the rear wheels are driven and the front wheels are idlers>use tank controlsthe main concern here is how to reliably drive the rear (now front) wheels>chain drivewon't work for reverse drive. I could make it a "pusher" if I used a bungee cord or similar on the steering bars to keep them mostly straight. but only being able to go forward is annoyingone way around the above is to get two fixies. or get a derailer and weld it solid>friction drivetake stepper motor, maybe attach a small wheel with some grippy pattern, then push it into the mtb wheel using a spring or weight>some kind of separate drive wheelseems kinda stupid when I have two/four wheels right there
electrics:>solar panel (already have)>lead-acids because I have lots of them and no one is going to steal them and if I mount them low they will act as ballast>MPPT charger (already have)>SMPS for 5V>raspberry pi for the brains>stepper drivers>webcams to see where I'm goingon the software side I'm thinking just streaming the webcams using ffmpeg. driving the steppers I imagine a similarly simple thing on the rover side. move all the smarts to the server. the user just sends a list of "rotate the steppers this many steps over this amount of time and stop" which can be done using a simple python script
>>2996776Watch Clarkson's Farm. He has one in the most current season.That is to say, they already exist. So just copy that.But also watch Clarkson's Farm. The man is a walking disaster and very entertaining.
>>2996794yeah I've watched the latest season of Clarkson's Farm. the man is insufferable and probably terribly to work with, but he is amusing to watchstill, these systems cost a ton and I'm sure something similar could be hacked together
>>2996776
>>2996776Consider how your machine will move between the rows of your crops and build with that idea in mind. Your bikes don't need to be exactly a solar panel apart, the solar panel can hang over the edges and just be sitting ON the nutbuster bar.If you are married to using bikes, I would turn them into fixies. I can't imagine turning a standard bike into something like that would be expensive, and then mounting 2 motors wouldn't be crazy hard either. You need to consider more of how you are going to kill the weed. Lasers are a surprisingly a bad move (plants suck up water and are hard to burn out) so I would try something like a weedwacker head and motor attached to a liner actuator that could slide around on a pair of rails. Just move the contraption over what you want to kill, lower the wacker, and murderize it. Make sure to put a camera on the bottom so you can see what you are aiming at.
>>2996841I was thinking something like the head on the weedinator. it's got kind of an eggbeater shape. see picrel>Consider how your machine will move between the rows of your crops and build with that idea in mind. Your bikes don't need to be exactly a solar panel apart, the solar panel can hang over the edges and just be sitting ON the nutbuster bar.this thought struck me as well. but I really only need the distance to be some multiple of the row pitch. if rows are multiples of 1 dm apart then I want the distance between the wheels to be some highly composite number of dm. 24 happens to be a highly composite number>If you are married to using bikes, I would turn them into fixiesI'm not really married to the idea. it just seems easier than building an entire frame from scratch. I could ask my bicycle repair man for advice. maybe even have them do the conversion, and stick the biggest possible rear sprocket on them. then some suitable large steppers. bonus points if NEMA 17 is enough. but I suspect they would require a worm gear to the front sprocket. I only really need like 100 meter/h top speed
>>2996841oh and 2.4 meter is really wide track which should make it less likely to tip over in the wind
>>2996841> Lasers are a surprisingly a bad moveI live in a farm country and almost all of the robo weeders use lasers now, earlier ones used gas flames. But they run often and catch weeds when theyre still very small. You don’t have to burn a weed off completely, you just have to get the moisture temp inside to like 55C and it dies off. Some weeds grow from a tiny bit of root so shredding them up and leaving them on the field only makes the problem worse. >>2996777Can’t you flip the chain side on both ends to invert the direction? Also iirc it takes just two spot welds to turn a freewheel into a fixie if you have the tools to take the hub apart
>>2996876>Can’t you flip the chain side on both ends to invert the direction?... yes. now I feel a bit silly. but also I still probably need to be able to reverse. so either handing the bikes into the shop or getting the tools to take the hub apart. then figure out a good stepper mount, but I've proficient enough with freecad that that shouldn't be an issue
>>2996878> "rotate the steppers this many steps over this amount of time and stop"Doesn’t this kind of beat the purpose of using stepper motors? There will be a lot of slip driving uneven sandy terrain unless you have a ton of mass, I could be wrong but I don’t really see the advantage over using ready made direct drive hub motor. You’ll need to get most of the feedback from camera anyway and don’t need holding torque> cameraCurious to your idea of navigation, will you slam map the entire field each time? Will it be like a line follower robot?
just hire a mexican to weed your garden once a week
>>2996939there are no Mexicans where I live
