DATA 

 COLLECTION 

 ON ANALOG 



TAPE 



Force Pulse Testing of Ship Models 



ANALOG 



DATA 

 DIGITIZED 



HARMONIC 

 ANALYSIS 

 ON 

 7090 



FILE 

 SELECTION 



AND 

 TITLE CARDS 



CRT PLOTS 

 OF 



FREO 



TRANSFORM 



COMPUTATION 



7090 



» CRT PLOTS 



PRINT OUT 

 FREO 

 XFORM 



<> 



MATRIX 



INVERSION 



OF EQUATION 



COEFFICIENTS 



PRINT OUT 

 OF 



Fig. 7 - Digital analysis system 



Xj = surge (positive forward), 



Xj = sway (positive to port), 



X3 = heave (positive upward), 



X4 = roll (positive deck to starboard), 



X5 = pitch (positive bow downward), 



Xg = yaw (positive bow to port). 



If the excitations are sinusoidal with frequency w , we can write 



fi(t) = p. cos (wt+ e.) 



and Eq. (1) reduces to 



^i(n = E Fi 



(R^j)' + (Rfj)' 



1/2 



cos (ojt + e^ - e^j) 



(2) 



221-249 0-66-30 



449 



