Biomimetic design of an underwater robot inspired to the cownose ray

This paper shows the design of an underwater autonomous robot. The challenges of this activity are mainly linked to motion design and to energy efficiency. Therefore, a bioinspired approach has been used. Batoid fishes swim moving their pectoral fins, they produce a wave travelling in the direction opposite to their motion, pushing water backwards and gaining thrust as a consequence of momentum conservation. The motion of the fin has been studied and reproduced with a series of articulated mechanisms. In this work the optimization of the mechanism’s geometry is described and the experimental results on the reconstructed fin are presented.