Abstract: This study focuses on the design, development, and testing of a soft robot that emulates the contraction pattern of the Craspedacusta sowerbyi jellyfish, which has been analyzed using image processing techniques. This prototype is mainly composed of a 20.4 cm diameter silicone body that possesses a set of backbone structures supporting a pair of braided Shape Memory Alloy wires that, once activated, produce a change in the shape of the body. Each pair of braided wires provides agonist–antagonist motion; the first has a 1.4 mm diameter and produces a bending of 2.3 cm in the backbone structure that generates the contraction of the jellyfish bell; when the second wires, which possess a 1 mm diameter, are activated, the bell of the jellyfish expands by changing the backbone structure to a straight shape. The implementation of the contraction pattern is achieved through the sequential activation of the braided wires using electric relays; this pattern takes 10 s to execute and provides a motion speed of 15.6 mm/s. The proposed architecture for the jellyfish robot allows for a smooth shape change that generates underwater motion without creating vibrations that affect the life forms in the environment and includes a camera to perform exploration tasks.

Key words: Bio-mimetic robot')">Bio-mimetic robot, Smart actuator, Shape memory alloy, Soft robot, Jellyfish