I have been told that Japanese police have wands similar to what you are
building that are used in crowd control situations.  The wands have a
short handle perpendicular to the main wand.  The wand is swung about
the handle by the operator.  An optical encoder at the junction of the
wand and handle is used to clock character (row/column - should be
azimuth/radius) pixels into the display.  The handle is kept from
rotating  by being held firmly by the operator.

Regards,
Dave Minkler

Brian Jones wrote:
>
> As a simple project for my local radio club I've designed a PIC
> Magic Wand that flashes 7 LEDs leaving a trailing message in the
> air. The flashing (ie message) is triggered by motion sensored by a
> mercury switch.
>
> Works fine if you wave right to left but moving left to right the
> message is mirror imaged (of course).
>
> Any ideas on a simple (and cheap) method of detecting whether
> motion is left-right or right-left so I can invert the message as
> appropriate. 2 mecury switches mounted in some way so that the
> leading edge triggered first seems the obvious solution but how to
> actually implement this?
>
> Thanks
>
> Brian
> Brian E Jones
> Centre for Java Technology
> IBM HURSLEY
>
> --
> http://www.piclist.com hint: The PICList is archived three different
> ways.  See http://www.piclist.com/#archives for details.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.