Re: [mowbot] Cheap accurate location

Mike Ross (mross nospam at
Mon, 26 May 1997 15:06:36 -0500 (CDT)

On Mon, 19 May 1997, Monta Elkins wrote:

> BTW the problem of visibile satellites is a rather small
> one given the relative proximal location of the two
> receivers for typical mowbot applications.

Agreed. The problem would be one of finding an identical set of
satellites with good GDOP placement sufficient for both units. If the
base station had a full sky view, then I'd think a good subset for the
roving unit could be found. The Trimble units I used could be commanded
to use certain satellites, which I tried, but the readings didn't improve.
I could have had a coding error as well, since the window was limited.

I still say there must be some reason someone hasn't done this, just
because of the huge price disparity. I mean, think of the possibilities
of $300 absolute positioning with millimeter accuracy. If you've figured
out a patentable way to do it, let me know when you go public :-)


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