Boundary measurements.

Best regards

Iain

I have pasted the reported file structure for the *.vhd file below. If all distances are reported in meters (mm perhaps), then why do columns 15, 16, 17, 20, 21 and 22 report distance from probe to each beam in counts?

Best regards

Iain

 1   Month                            (1-12)

 2   Day                              (1-31)
 3   Year
 4   Hour                             (0-23)
 5   Minute                           (0-59)
 6   Second                           (0-59)
 7   Burst counter
 8   No of velocity samples
 9   Noise amplitude (Beam1)          (counts)
10   Noise amplitude (Beam2)          (counts)
11   Noise amplitude (Beam3)          (counts)
12   Noise correlation (Beam1)        (%)
13   Noise correlation (Beam2)        (%)
14   Noise correlation (Beam3)        (%)
15   Dist from probe - start (Beam1)  (counts)
16   Dist from probe - start (Beam2)  (counts)
17   Dist from probe - start (Beam3)  (counts)
18   Dist from probe - start (Avg)    (mm)
19   Dist from s.vol - start (Avg)    (mm)
20   Dist from probe - end (Beam1)    (counts)
21   Dist from probe - end (Beam2)    (counts)
22   Dist from probe - end (Beam3)    (counts)
23   Dist from probe - end (Avg)      (mm)
24   Dist from s.vol - end (Avg)      (mm)

Those fields refer to the echo amplitude magnitudes on each acoustic beam, not the distances measured. The echo amplitude needs to be strong enough for a boundary location to be determined. If it is too low no distance will be reported (reported as 0.0 in the data file I am looking at).