EXPERIMENTAL TECHNIQUES AND METHODS OF ANALYSIS 
USED IN SUBMERGED BODY RESEARCH 
Alex Goodman 
David Taylor Model Basin 
This paper deals with the various experimental techniques and methods 
of analysis which are either presently being used or are contemplated in 
the near future at the David Taylor Model Basin in the field of dynamic 
stability and control of submerged bodies. The advantages and disad- 
vantages of the various techniques are discussed. Primary emphasis is 
placed on the principles and operation of the DTMB Planar-Motion- 
Mechanism System, since this device is unique and is being used exten- 
sively to provide stability and contro] data for submerged bodies in six 
degrees of freedom. Emphasis is also placed on the concepts, tech- 
niques, and philosophies used in simulator studies and motion analyses. 
A brief description of the new rotating arm facility, and the free-running 
model technique are also presented. 
NOTATION 
The nomenclature defined in DTMB Report 1319 is used herein where applicable. The 
positive direction of axes, angles, forces, moments, and velocities are shown in the accom- 
panying sketch. The coefficients and symbols are defined as follows:* 
Symbol Dimensionless Form Definition 
A, 
A, A, = =a Projected area of bow planes 
A, 
A, Sa Projected area of rudders 
12 
' os 
A. A= oy Projected area of stern planes 
AP After perpendicular 
AR Aspect ratio 
*All derivatives with respect to angular quantities are given as “per radian.” 
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