At 04:56 PM 11/18/97 -0500, you wrote:
>You could also have a fixed laser which does not turn, and place the yard
>on a large turntable with a motor under it being controlled by an H-bridge
>which is attached to a PIC. This totally eliminates the burgaler problem
>because the burgalers couldn't get onto the spinning platform.
>
>Sean

Why not bury the laser vertically in the lawn. The PIC then lifts and
rotates a mirror to direct the laser beam. With a few suitable sensors this
could also be used to prevent cats 'visiting' the flower beds too. It could
even do the weeding. You simply have a database of plants on your PC, and
the Laser scans the remaining area every week or so.

Keith.