Re: [mowbot] Software discussion

Dave Everett (deverett nospam at
Wed, 22 Sep 1999 09:31:18 +1000

At 09:52 21-09-99 -0400, Raymond Skarratt wrote:
>Hi all,
>Things have been a little quiet lately. I thought it would be good to get
>another discussion going and hopefully get as many people on the list as
>involved as possible.
Well Ray, good to hear you're still around mate :)

>So let's say for the purposes of discussion that we would like to see the
>mowbot cover a specified area and not run outside this area. Let's also say
>that we would like the mowbot to cover the area in a reasonable amount of
>time. I think that I would probably like to exclude a random-path
>implementation from our discussion. The random-path solution will probably
>end up being a special case of any solution we come up with. One of the
>main problems that I see will be boundary detection.
I believe there are only 2 real detection requirements to meet the spec of
a robot that covers the whole area and stays within the bounds.

For the purpose of this discussion I am proposing a simplified layout:

1) the boundary region must be marked by either:
a) a solid fence at least 6" high
b) a non-grass region

2) the grass should be long enough to register with a set of slotted IR
fingers at the front of the robot.

The robot would use only these sensors:
1) Slotted IR fingers at the front (5 to 7 slots)
2) floating outer cover that produces bump information

Using these 2 sensors the robot would start on an outside edge and work
it's way in feeling around obstacles until the entire region was cut.

Dave Everett

Domestic Droids Website