For all the Roombas in the world, you have to wonder why robotic lawn mowers aren’t more common. Sure, you can go out and buy one, but mowing the typical suburban yard is a piece of cake for a robot; there aren’t stairs, there are relatively few obstacles, and a boundary wire system is much simpler than simply bouncing into things like an iRobot.

[Schuhumi]’s autoCut is the only household robot to make the semifinalists in The Hackaday Prize. Underneath, this bot is electric, has fully automatic operation, and even has a motor to change the height of the blades. The blades are actually designed more like a stringless weedwacker; the blades pivot back when they encounter a hard obstacle, although this safety cage is a really good idea

Instead of doing the random ‘bump and turn’ algorithm found in a roomba, there’s a lot of thought put into navigation with this bot. [schuhumi] is using ultrasonic navigation that triangulates the position of the bot in a yard. That’s a great idea; there’s no need to waste time or power rolling over what the bot has already cut.

You can check out [schuhumi]’s overview video and a demo below.

The project featured in this post is a quarterfinalist in The Hackaday Prize.