In order to stably receive or transmit the signals of satellite antennas or TV receivers mounted on a moving ship, it is necessary to stabilize the platform of the ship. The motion of the ship is a six degree-of-freedom motion and is composed of surge, sway, heave, roll, pitch and yaw component. Components related to the stabilization of the ship are the very roll and pitch component and they are independent each other.
To stablilize the platform of the ship is to comprise feedback control systems for each rolling and pitching plant, which follow the reference input signals corresponding to the opposite directions of the roll and pitch angle detected from the moving ship.
This adaptive fuzzy control algorithm is especially useful for systems whose mathematical models are not easily found owing to the geometrical complexity, parameter uncertainty and etc. The adaptive fuzzy control algorithm suggested in this paper, is a 2nd/1st-type indirect adaptive fuzzy control algorithm utilizing only the advantages of 1st-type and 2nd-type indirect adaptive fuzzy control algorithm in order for a microprocessor to accomplish control algorithms with a computational efficiency.
There is a great number of on line computational parameters when the fuzzy logics of the adaptive fuzzy control algorithm are accomplished. In order to compute them within a real time sampling period, the TMS320C31 DSPs were adopted and real time controllers were composed using the DSPs as a central instruments.
To prove the effectiveness of the suggested control algorithm computer simulations were accomplished. To test the usefulness and the possibility of the real time control within 10 msec sampling period experiments were executed. According to the results of simulations and experiments, the suggested control algorithm turned out effective and the attitude stabilizing control system of platform of ships exhibited a very good control performance with tracking errors within ±0.5°for each time-varying roll and pitch command angle.