Design methods for miniature underwater soft robots

A robotic fish accepted by animals as conspecifics
is a very powerful tool in behavioral biology. To obtain the
acceptance of the device towards the animals, it should generate
some visual stimuli that can be perceived by a living fish as
attractive signals. In this paper we introduce a novel design
of a robotic fish lure based on a Rigid-Flex Printed Circuit
Board (PCB) for experiments on the fish collective behavior.
The 3D scan of a zebrafish Danio Rerio, a model animal for fish
behavior studies, was used to mimick the main visual features
of the zebrafish on the design. The robot can generate different
stimuli thanks to its actuated caudal peduncle and two Light-
Emitting Diodes (LEDs) placed near its eyes. The prototype has
a total length of 63 mm and is only 1.5 times bigger than a
zebrafish. The final prototype is waterproof and functional and
thus satisfies the necessary conditions for the next steps that
will be interaction experiments between the device and living
zebrafish.