Measurement and compensation system for beam forming array

A method for operating an acoustic beam forming detection system comprising a flexible linear array of discrete acoustic sensor elements, and delay elements respectively coupled to the elements, said method comprising the steps of:

• moving said array through a water environment;
• measuring the velocity of the leading element of said array at the beginning of an initial cycle of selected time duration;
• estimating what the positions and velocities of each of the elements will be at the conclusion of said initial cycle, said initial cycle estimates being based upon the assumptions that said array is in a linear configuration at the beginning of said initial cycle, so that the positions of the sensor elements with respect to one another are known, and that the velocities of each of said sensor elements at the beginning of said initial cycle are equal;
• measuring the velocity of said leading element at the beginning of an updating cycle of said selected time duration, said updating cycle commencing upon the conclusion of said initial cycle;
• estimating what the positions and velocities of each of said sensor elements will be at the conclusion of said updating cycle on the basis of the measured velocity of said leading element at the beginning of said updating cycle, and on the basis of position and velocity estimates made during said initial cycle;
• and
• continuing a succession of said updating cycles until estimates of the positions of said sensor elements are provided which are sufficiently close to the respective actual positions of the sensor elements that said array may be employed to detect the bearing of an acoustic signal source to within a selected degree of error.