The organized motion control of multi-directional wave maker

Abstract

This paper describes the hardware and associated software of the organized motion control of a multi-directional wave maker which has been developed in the seakeeping model basin. The developed wave maker is a flap type wave maker which consists of multi-segmented flaps, actuators (AC servo motors) which drive segmented flaps, and the computer system which manages the motion control of actuators. Waves can be generated by the forward and/or backward movement of flaps which are connected mechanically by ball screws rotated by AC servo motors. How the flaps are moved decides the type of waves such as the wave height, the wave period, and the wave spectrum, etc. The width of the test basin and a flap size are 30m and 0.4m, respectively. Therefore, the number of segmentation of flaps becomes 75. The computer system drives simultaneously these 75-axes AC servo motors. The organized motion control of 75-axes-servo-system for the multi-directional wave maker is completed and the high performance of the wave generation, especially the real time calculation of setpoints, is achieved by the organized motion control hierarchy design.