Reduction of fish´s learning speed by chaos and randomness in antagonistic relationship of robot and fish

In this paper, we report relative comparison on leaning speed of fish in an antagonistic relation of prey and predator-the prey is a fish and the predator is a robot seeking to catch the fish by a net attached robot´s hand through 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 have been measured as learning speed that describe decreasing tendency of how many fish could be caught in constant time when the fish caught being 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, where some experiments are conducted to examine whether chaos and randomness can decrease the fish´s learning speed.