Building A Homebrew Robotic Lawnmower?

mmonkey writes "With the seemingly small amount of summer we get here in the UK, the last thing I want to be doing on a sunny day is mow the lawn. So I started thinking "surely a light-ish lawnmower could 'gain' a couple of motors, and suddenly be computer-controlled?". Then I started thinking about stuff like obstacle avoidance, optimum path planning, guidance system, how to get pretty-looking stripes, and I realised that it's actually a potentially complex (read: fun) thing to do. So, have any Slashdotters done this before? Did you modify an existing lawnmower or build a whole new one from scratch? What motors work best? For that matter, what type of mower works best? I know you can already get these, but that detracts from both my geek-drive and my wallet, both of which I'd prefer to keep as full as possible."

Comments

Autonomous Lawn Mower Competition

[Tekmage]

There was an Autonomous Lawn Mower Competition going on earlier this month - saw it mentioned on robots.net

Hardware Ideas

[Eisenfaust]

If I was going to do this, I would start here (I've used their products for years).

http://www.tri-m.com/products/engineering/index. ht ml

I would use the MZ104 CPU Board. They have a Linux distro you can throw on a DiskOnChip pop that in along with a regular old 64mb laptop SODIMM and you are good to go.

You can use the IR104 i/o board to provide 20 digital inputs and 20 digital outputs. This should allow you to hook up some simple sensors as well as giving you control capability. You may also need some sort of Analog I/O board, but I would avoid this for cost reasons.

The MZ104 CPU Board also has an I2C Bus interface with linux driver support. There are a plethera of different sensors available that you can directly read from this simple two wire bus.

These products are extremely affordable, rugged, low power and small. The entire system can run off of 5VDC. You can even lower the clock rate to save power.

If you do decide to go along with this, please add a wifi card and a web cam so we can watch it mow in real-time.... (uhhh oh slashdotted lawn mower)

You could obviously do this with something that had a lot less horse power, like an 8051, HC11 or Z80, but you would have to make up a lot of custom circuitry to get the job done. I like the modular nature of the PC/104 form factor. If you do opt for something with less power, I would definately make sure it has a built-in i2c controller.