GB1215440A - Apparatus for determining characteristics of a marine swell - Google Patents

Abstract

1,215,440. Electric correspondence control systems. COMPAGNIE FRANCAISE DES PETROLES, S.A. May 1, 1969 [July 5, 1968], No. 22278/69. Heading G1N. In apparatus for determining the level, direction, speed and wavelength of marine swell, a buoy having three cylinders 3, 4, 5 rigidly spaced around a body 1 is anchored, each cylinder containing three spaced water level gauges 12 e.g. capacitance gauges providing electrical signals indicating changes of water level in each cylinder, and means being provided for producing electrical signals representing the angular relation between a system of co-ordinate axes defined in relation to the buoy and a fixed system of co-ordinate axis. As shown, signals from the water level gauges 12, together with signals from level gauges 22 representing the attitude of the buoy relative to the vertical and signals from a compass 23 representing the heading of the buoy, are fed to a transmitter 21 which applies in output directly to a recorder 33 on the buoy, or to a computer 20 and recorder 30 or a recorder alone over a radio or transmission line. The attitude of the buoy may alternatively be measured using a pendulum or gyroscope. The measurements may be carried out continuously or at fixed intervals.