Fig. is a schematic of the intention generator of a predator, which is a specialized version of Fig. . To simplify matters, currently predators are not preyed upon by other predators, so they perform no predator detection, and escape, school, and mate intentions are disabled (F=0, L=0). Since predators cruise perpetually, the leave intention is also disabled.
Figure: The intention generator of a predator.
Generally potential prey are in less danger of being hunted when they are far away from the predator, or are in a school, or are behind the predator. A predator chases prey k if the cost of reaching it is minimal. This idea is based on the optimal foraging theory in ethology, which in its original form states that when an animal is feeding it makes its decisions in such a way that it will maximize its net rate of energy intake [Manning1979]. We model the cost of feeding on prey k as , where is the distance between the mouth of the predator and the center of prey k's body, if prey k is in a school of fishes, otherwise , and the angle (Fig. and Fig. ) measures the turning cost. and are parameters that tune the contributions of and . We use and in our implementation of the focusser.
Figure: The angle .
|Xiaoyuan Tu||January 1996|