Differences

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--- rini:speed_log_notes [2009/04/17 05:07]
ben
+++ rini:speed_log_notes [2009/04/17 06:37]
ben
@@ Line 30: / Line 30: @@
 D = Y/X * 1 n.m.
 T = Z/3600
-So:  (Z/X * 1 n.m.) / (Z/3600) = Speed in knots for the sample period Z
+So:  (Y/X * 1 n.m.) / (Z/3600) = Speed in knots for the sample period Z
-E.G.  If we calibrate 1 n.m. at 2500 clicks (X=2500) and our sample/update period is 2 seconds (Z=2), and over that period we count 30 clicks (Y=30), then calculated speed would be (30/2500)/(2/3600) = S = 0.012 / 0.0011 = 1.0909 knots.
+E.G.  If we calibrate 1 n.m. at 2500 clicks (X=2500) and our sample/update period is 2 seconds (Z=2), and over that period we count 10 clicks (Y=10), then calculated speed would be (10/2500)/(2/3600) = S = 0.004 / 0.0006 = 6.67 knots.
+Hopefully we get faster turn rates that 5 rotations per second, otherwise it won't be very precise.
 </blockquote>

..., etc.