Reduction of Fish's Learning Speed in Antagonistic Relationship of Robot and Fish

—Trials Using Chaos and Randomness—

Abstract

In this paper, we report relative comparison on leaning speed of fish in an antagonistic relation of prey and predator—the prey is fish and the predator is a robot seeking to catch the fish by a net attached robot's hand by means of visual servoing. It was confirmed that the fish have found escaping strategy by itself, e.g., staying at corners of a pool where the net is inhibited from closely approaching to the corners to avoid the net clashing to the pool wall. The effectiveness of the conceived escaping strategies by fish has been measured as learning speed that describe decreasing tendency of how many fish could be caught in constant time when the fish caught be released immediately to the same pool. To overcome such fish's ability to conceive new strategies for escape, in this paper, chaos and randomness have been added to the net motion. The effectiveness of chaos and randomness are experimentally examined to judge whether they can decrease the fish's learning speed.