Figure 8.18 shows an output from the acoustic mapping system
when used during a topographic mapping procedure. The vertical
and horizontal directions are the wheel perimeter and width respectively,
with a spatial resolution of 2 samples/mm. The depth of interaction
between diamond tool and grinding wheel used was 1 micron
(in the range of elastic contact). The color intensity shows the acoustic
emission RMS value measured from the interaction between
dressing tool and the abrasive grains. Darker areas correspond to
lower acoustic energy detected by the sensor. The L shaped mark
was created in the wheel surface in order to evaluate the system performance.
Dark areas show worn regions of the wheel where the
dressing tool had lower interaction with the abrasive grains. The
main vertical worn band on the left side was a result from a grinding
operation made with the workpiece shown in the photo of Figure
8.18a. In this figure, the “L” mark produced on the wheel surface
and a magnified view of its representation in the AE graphical mapping
is shown.