Research on Pitch Motion mode of SWATH based on System Identification

Zhaozhao MA, Songlin YANG, Shasha GAO, Zhanyuan CHENG, Baojiang WANG, Di ZHANG

In this paper, a series of static water pitching attenuation tests were carried out on a small swath unmanned underwater SWATH-USV under different draft and different initial pitch angles. By changing the composition of the restoring moment and damping torque, 9 mathematical models of the system identification were established. By changing the composition of the restoring moment and damping moment, a systematic identification mathematical model for 9 modes of pitch attenuation motion was established. Based on the system identification theory and genetic algorithm, the system identification software was written in C# language. The experimental data of the unmanned craft were identified and analyzed, and a good mathematical model of the longitudinal pitch motion was obtained by identification and calculation, and the changes of the parameters of the identification parameters under different water and tilt angles are compared. The variation of each identification parameter at different draught and tilt angles was also compared. The relative error between the software forecast value and the test value shows that the prediction value is in good agreement with the test value, which proves the reliability of the system identification software, and can predict the future navigation and motion posture of the unmanned craft.

https://dx.doi.org/10.31873/IJEAS.5.10.02