Hybrid computer simulation of maneuvering during underway replenishment

Article type: Research Article

Authors: Brown, S.H. | Alvestad, R.

Affiliations: Control and Automation Division, Naval Ship Research and Development Center, Annapolis, Maryland, U.S.A.

Abstract: This paper describes a hybrid computer simulation of ship maneuvering during underway-replenishment operations. Two identical Mariner class merchant ships are used in this study. However, the simulation is easily adapted to any class of surface ship. The ships dynamics are simulated on an EAI 680 analog computer, while the nonlinear interaction forces are generated on a PDP-15 (DEC) digital computer. This first phase of the project considers only the interaction effects on the leading ship due to the close proximity of the tracking ship. Computer rims are made to study control of the leading ship for various fixed lateral and longitudinal separation distances. Manual control of the leading ship is also undertaken as the tracking ship passes. Preliminary studies indicated that the variables necessary for control of the leading ship in this idealized underway replenishment operation are: yaw angle, yaw angle rate of change with time, longitudinal and lateral separation between the ships, shaft revolutions per minute, and rudder angle. Phase II of this project will include the mutual interactions between the two ships and the effects of a sea state. Phase III will be directed to establishing the essential control variables needed for ship control during underway replenishment and the required accuracies of these variables.

DOI: 10.3233/ISP-1974-2124101

Journal: International Shipbuilding Progress, vol. 21, no. 241, pp. 259-275, 1974