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taken each day.Figure 8: Priority 1 cast locations were acquired with the SBE FastCat 49 CTD on the REMUS AUVJuly 8 and priority 2 cast locations were acquired July 9. All casts were at three dierent times of thetidal cycleThe SBE 49 FastCAT CTD data was run through Velocwin to calculate the sound speed see if theindividual sound speed proles could be detected and split up from the others.3 Results3.1 Algorithm Results and RenementAfter assessing the data acquired from our July 8-9 experiment we found that 13 of the 24 casts takenon July 8 and 20 of the 24 casts taken July 9 were properly determined using a basic algorithm whichwas incorporated into Velocwin (Figure 9).10
Figure 9: This image is of the vertical track of the REMUS on July 8 (day number 190). In this imagesound speed casts acquired by the REMUS are indicated by the green circles. The downward dives thatwill be used to create a SSPs were detect using a basic algorithm. Note the beginning of the downwardcasts are in green squares and their respective ending locations are in magenta square (note: not manycasts are detected). Black curve indicates nominal bathymetry prole. The same is also true for Figure10. Please note for the remainer of this paper, each dive that travels all the way to the seaoor and isdetected by the algorithm will often be referred to as a sound speed cast since it is generally the samepattern as manually lowering a CTD.On closer inspection we noted that there were more casts acquired by the REMUS than we had inputinto the REMUS program. This was due to the emergency climbs which occur when the REMUS's sensordetects the seaoor unexpectedly rising beyond the set buer. In order to detect more sound speed casts,we rened the basic algorithm to take into consideration the local bathymetry.The basic downward cast detection algorithm works (for each cast) as follows:1. Remove any duplicate time/depth values and get a unique set of times and depths to work with,2. Find the global minimum (Hmin) and maximum (Hmax) depths of descent by the AUV and letD= Hmax - Hmin3. Specify a percentage, r (1%-5%) and examine to see when the AUV depths (as a function of time),h(t) satisfy the dual-inequality Hmin + rˆD ≤ h(t) ≤ Hmax + rˆD and if so, also whether sets ofthree consecutive depth values (h(t) itself, the values before and after it) generate average negativevertical descent speeds (ie. the AUV is sinking)4. Continue the iteration in 3 until either h is outside the depth range or the vertical descent speedreverts back to a positive value via zero (the latter condition is what usually occurs) and,11
Page 1 and 2: An integrated approach to acquiring
Page 3 and 4: and rene our algorithm which would
Page 5 and 6: ≤ Δy ≤ 3380m in the two spatia
Page 7 and 8: Figure 4: Image of 3 REMUS AUV CTD
Page 9: Figure 6: Tides for Solomons, MD Ju
Page 13 and 14: Figure 10: This image is of the ver
Page 15 and 16: Figure 12: Vertical path of REMUS o
Page 17 and 18: osets could be due to an initial os
Page 19: Shchepetkin, A. F. and McWilliams,

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