>
>I notice that there has been no mention of safety, specifically to prevent
>tiny toes and inquisitive fingers getting chopped off.

On any abnormality, you need to remove power from the motor, and apply a
0.1 ohm resistor across the motor.
This converts the energy stored in the blade to heat real fast.
It's about the best that you can do.  My B+D mower does this if you let go
of the handle.


>Tilt sensors activated at no greater than 20 degrees from horizontal.
>Activation shuts down machine.

Some yards are kinda bumpy. Acceleration is indistinguishable from tilt.


>After that comes the boring bit, Sitting on the stoop, drinking
>Sundowners watching it work and watching the neighbour's trying to
>pretend it doesn't exist.

Dress it up, so it looks like a normal (if large) mower.
Then when the new neighbors come by, pretend to be using your psychic
powers to push the mower.
They'll laugh for a moment, then when the mower turns around for the next
row.....
:)

You realize that 250 years ago, this technology would get you burned at the
stake

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