Page 429 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

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CHAPTER 15 Sonar
Transducer
H
r
r h
Target height h 􏰀 (H 􏰁 s)/(r 􏰂 s) (valid only on flat level bottom conditions)
Use shadow length to compute target height
Range to end of shadow (R)
s
s
Towfish height (Hf)
Formula for Ht solution:
Ht = Ls x Hf / R
Length of shadow (Ls)
(a)
H
(b)
Height of target (Ht)
FIGURE 15.35
Target height calculations (a) with transducer graphically depicted and (b) shown with tow fish superimposed.
FIGURE 15.36
Beam sweeping
Concept of electronically sweeping multibeam and commercial application.
(Courtesy SeaTrepid.)