It takes a lot of power and energy to keep grass levels down to an appropriate level; especially when it’s hot out. If cool glasses of lemonade aren’t around, the task at hand may not be completed any time soon causing the unkempt blades of green (or yellow) vegetation outside to continue their path of growth towards the sun.
Instead of braving the oven-like temperatures which will inevitably drench the person in sweat, this solar powered robot has been created ready to take on the job. With the heart of an Arduino, this device shaves down the grass on a regular basis, rather than only chopping down the material when it gets too long. This helps to save electricity since the mower is only dealing with young and soft plants whose heads are easily lopped off without much effort.
Internally, the robot’s circuitry interfaces with an underground wiring system that defines the cutting zones within the lawn, and proves to be a simple, accurate, and reliable approach to directing the robot where to go. If the device travels under a shaded area, a battery kicks in supplying energy to the engine. When sunlight is available, that same battery accumulates the electricity, storing it for later.
There is also an interesting mechanism in place that allows the controller to detect if the wheels are moving properly or if one or more of them have locked up. This is done by using a reed sensor that has been added near the rear-pivoting wheel which is then operated by a small magnet that is inserted into that same wheel.
Obstacle recognition is accomplished in the front by an ultrasonic sensor that is connected to the I2C BUS. A brushless motor, used in the field of aeromodelling, was coupled into a cutting blade. With everything set up, the solar powered lawn mower is ready to be unleashed into the outside world of unsuspecting, growing plants.
Now sit back, relax, and let the robot do the work for you.
For more grass cutting related hacks, be sure to check out this remote-controlled lawn mower, and this monster truck lawn tractor that can go through water.
well done.
Indeed WELL DONE… +1
;^)
I’d like to see a video of this thing in action. Mostly, I’d like to see that little brushless motor swing a motor blade. I also have doubts about the wheel motors being able to pull it across most yards. However, if it actually works with such small motors then I’ll be the next to build one!
If you read the tail-end of the article, you’ll see that it mentions that the robot is mostly a proof of concept:
“Far from being a lawn mower that can substitute a commercial product (that has very different pricings), it can be useful to understand the real possibilities of this kind of robot.”
That said – the main control scheme and such isn’t too much different than what was in the Friendly Robotics lawn mower (which was a full-sized commercial robot lawn mower product).
those motors bottom out at about 8000rpm, I’d like to see what kinda cutter was set up for it
In other DIY robot lawn mowers I have seen (that were small like this one), the “blade” was some kind of bar with razor blades attached. You’d probably have to mow the lawn once (“manually”) before letting the robot “trim” the grass afterward. I’d say for a cutter, a simple piece of flat steel that was sharpened and heat-treated would work well enough.
You do not want to use hard steel for a lawnmower blade. What if you hit a rock? Hardened steel is brittle so it will shatter and send a projectile flying. It will also make your lawnmower run funny because now the blade is severely out of balance. Lawnmower blades are made out of soft steel so they are tough. You can also sharpen them with a file.
String trimmers are high speed. You can never get a really clean cut using string though. Not even that eight sided stuff. I’ve gone back to just using round string myself. Round string seems to be the toughest to me. I have some really rough areas I maintain. I basically keep the weeds low in some places to keep the bugs down. I can’t get my tractor in those places either because of the pitch of the ground.
It’s name was mobot or mowbot, the time 1965! Nothing has changed but the ‘duino. Not the e-fence not the small blades on a disc, nothing but the end of the American lawn. Just ask any Californian.
Watch out for dips and holes. It will just spin in place.
You can actually still get those, but the price is pretty damn high for a mower (cheapest on their uk site is £949.99 inc tax). Rolling your own is probably a hell of a lot cheaper if you know about electronics, although the underground wiring thing would add a fair bit of hassle to using it
Believe it, or not, the USA extends a bit east of California’s eastern border. The USA does not extend much further east than I am now though. A few miles. We’re close to being flooded out here this weekend too. We have plenty of water. Actually I just checked outside and I’ve no big bodies of standing water in my yard yet.
I have in the past though
http://img132.imageshack.us/img132/6593/flood2x.jpg
It is over a foot deep out in the middle. After that the state came in and dug the tax ditch again.
It’s all fun and games till it runs over the cat…
cat-terminator 6000
You probably couldn’t build a robot that can run over a cat if you tried. At least not a live one that isn’t buried up to its neck.
I dunno…. i’m kinda bummed it doesn’t show a single blade or cutting mechanism. I really wanted to see how it handled the cutting portion
Prove of concept/research – sure. The case design looks cool, but not practical.
Having LCD, push buttons and connector opening on the side is asking for trouble in real life. Lawn clipping etc can get to them and get inside. You want to at least put those things in a water proof cover and on top side. You want a lawn bot that you can rinse off with a hose.
Motor gear shaft driving wheel directly sure, but you really have to think about not having the full weight of that bot resting on a thin shaft. Don’t forget about ground clearance. It probably work great on the flat soccer field, but not in real life garden.
Still… I am scheptical it would make sense to build a real lawn mower that is solar powered. A small two-stroke gas engine is the way to go. It will give you all the power you need to do the job and it could also generate the required electricity to run all the circuitry.
mow for an hour, charge for a week
Hi, I add the video on the blog page
http://www.open-electronics.org/a-robotic-lawn-mowers-powered-by-solar-energy-with-an-arduino-heart/
I’m always wondering when a battery powered project is shown (where the size in not a limitation)
why the batteries are not replaced by a supercapacitor bank?
Something like this one:
http://www.maxwell.com/products/ultracapacitors/products/48v-modules
You might want to compare prices.
Yeah, I forgot to mention, that from time to time you may get one of these banks at a reasonable price on one of the bigger auction sites.
This might be more common if there were “plug and play” tutorials – batteries are seen as relatively benign and big power capacitors as trouble waiting to happen by a lot of people. Neither of these is completely accurate.