Jump to content

My son is interested in robots so I wanted to build one with him but I wondered, what kind of robot?


G+_Russ Hall
 Share

Recommended Posts

My son is interested in robots so I wanted to build one with him but I wondered, what kind of robot? Last summer, mowing the lawn, I realized what I wanted: a robotic lawn mower! Not one that crosses the yard at random angles and not one remote controlled. No, a true, intelligent robotic lawn mower that knows where and how to drive itself around efficiently. Who has built one?

Link to comment
Share on other sites

Better still why not make a remote controlled lawnmower with a joystick and webcam. But it has to look just like the lawnmowers you push along yourself.

 

You sit inside on a hot day and drive the lawnmower around. Imagine watching the expressions of people passing by seeing a lawnmower mowing the lawn with noone pushing.

Link to comment
Share on other sites

One guy on Youtube has a lawnmower that flys! Seriously, I don't want to do remote controlled, because I still have to control the thing over its whole route.

I took a video from top of our push machine and fed frames of that into Labview. It found the edge of mowed lawn, so I thought I'd make one follow that guide. Another idea is a Kinect mounted on the machine to plot the entire yard and place exactly the mower where it should be in its route.

Link to comment
Share on other sites

There is a reason why robotic lawnmowers go in a random pattern. There isn't a reliable way to tracking something with enough precision that a lawnmower would need. The only way you could track it is through wheel movement, but if the wheel slips a little, you could be mowing down some bushes, or people. If you wanted to make a random pattern lawnmower, you could just use a modified dog's shock collar for the lawn boundary. Put some wheelchair motors on a push mower, and control the hole thing with an Aurduino. 

 

With all that being said, PLEASE DON"T MAKE THIS. Store bought robotic mowers have a ton of safeties in them to prevent the mower from wondering off, potently killing someone. With a push lawnmower, there isn't a way to stop the blade in time if some kid decides to pick up the lawnmower. Also, if you mess up the coding just a little, the mower could wonder off into traffic causing an accident. You don't want anyone's tombstone to read "Died from buffer overrun". Its just embarrassing. :)

Link to comment
Share on other sites

Sorry, didn't mean to freak, just hate to see someone create something without knowing what can go wrong. Remember, %90 of design is knowing how things can go bad. 

 

Anyway, if I remember correctly, the Kinect uses a grid pattern produced by IR. This is fine inside, but outside, your robots eyes would be blinded by the sun. And sunglasses, while would look awesome, won't help. :) Also, there is usually very little detail on a lawn, so it may not have anything to lock onto in the middle of your yard.

Link to comment
Share on other sites

I dont think giving the lense a shade would do anything. If you shine a light on the ground during day time, you wont be able to see it. The same thing would happen to the knect. Maybe what you could do is to mount a camera somware in your yard, put some type of marker on the robot, then track the marker through the camera. Sort of like what the do for tracking people in computer generated movies.

Link to comment
Share on other sites

I hope that I am not coming across as hyper critical or negative. I think that it is great that you want to help your son learn about robotics. Its just, what you are trying to accomplish is on par with an autonomous car. It is very hard to do. And, unless the both of you are like me; fueled by frailer, it may discourage you when you hit the wall of problems. I would recommend that you guys start small. Build a remote controlled robot (powered by an Arduino and an xbee modal). Not only would this teach you the basics (I hope that I am not wrong in assuming that you guys are just starting out), but it will give you a robotic platform, then you could use that to make a tellapresence robot, line following robot, or even an autonomous robot powered by the kinect.

Link to comment
Share on other sites

Thanks for the interesting comment. Yes, we know this is hard, but as hard as an autonomous car? I don't think so! This machine's world will be small and more predictable, and the very predictability of it makes it well suited for machine intelligence. Yes, you are right, we need intermediate steps. We built the Jameco Arduino office rover robot and Lego robots. We will try to break it down into steps.

Link to comment
Share on other sites

OK, I should have said almost. But Think about it, while yes your yard would be normally predictable, it wont always. What about squirrel, dogs, cats, kids, balls, You robot would have to identify these and figure out what to do, unless you make it just stop if anything gets to within 5 feet (which would be safer). But what makes it difficult is accuracy, You basically trading complexity for accuracy. You will probably have to be able to track the lawnmower within an inch if you want it to get close to the edges. And keep this accuracy for what, 50 to 200 feet; depending on your yard. And be able to see small/thin thing infront; like a baseball or a bike. Now, all of these things would be simple if you could this: http://www.robotshop.com/en/hokuyo-urg-04lx-ug01-scanning-laser-rangefinder.html. Than you can build a 3d map, and use the terrain to figure out where it is. I would have suggested it earlier, but the last time I saw one, it was about $5,000.

Link to comment
Share on other sites

  • 4 weeks later...
  • 2 months later...
  • 2 weeks later...
 Share

×
×
  • Create New...