Hawser tension was kept comparatively low by means of conventional PID control in the case of 3.5 meters of significant wave height as shown in Fig. 10. The average value for hawser tension was reduced using neural control, although the maximum value sometimes exceeded that of PID control.

　

 Both the maximum and average values for hawser tension in the case of 4.5 meters of significant wave height were reduced with neural control, as was the case for 3.5 meters of wave height, as shown in Fig.11.

　

 That is, it was verified from these experiments that neuro-control performance is superior to that of PID. In addition, it was shown experimentally that the maximum value of hawser tension in such rough sea conditions as 4.5 meter wave height can be reduced to the value for 3.5 meter wave height corresponding to conventional control.