The tilt sensor chosen is a CXTA01 by Crossbow Technology
Inc. It has a fully conditioned, absolute analog output voltage
that ranges between 0 and 5V corresponding to a 1-D (single axis)
tilt angle, with 2.5V corresponding to an angle of 0°.
The tilt sensor output voltage goes to an A/D converter
in the PIC microcontroller and its 8-bit result is sent to the
host computer. The angle is calculated by MatLAB and is an input
to the fuzzy logic controller.