Abstract
When numerous ducks stepped on rice in the duck paddy field, the blank zone was formed. On the other hand, it was observed that weeds grow thick by a small number of duck introduced. In order to perform appropriate management of the weeds in a duck paddy field, behavior control of a duck group was important. The techniques of measuring the position, the distance between individuals, and moving distance of a duck required for development of a duck simulator were devised. The positions of ducks were photographed as shown in a bird's-eye view with the digital camera. Their positions were measured on the basis of the seedling transplanted elaborately with the rice planting machine. The moving velocity of actual ducks was made into the parameter of the simulation program.The simulation program (Qoid) on the principle of the following three rules was developed. 1) An individual moves at random. 2) An individual moves toward the center of gravity of some neighboring individuals. 3) When their environment gets worse by stay of ducks, an individual searches for good environment. The simulations of duck flock swimming in the paddy field of a small and large scale were performed. Consequently, the virtual duck swam in every nook and corner in the paddy field, and the distance between the individual was close to the actual measurement. Moreover, the size of a sub-group was controllable by adjusting the number of neighboring individuals. The scene in which a virtual duck swims in the paddy field of various form was reproducible. The result of this simulation gave suggestion to the management of an actual duck paddy field.
