FludoJelly: Experimental Study on Jellyfish-Like Soft Robot Enabled by Soft Pneumatic Composite (SPC)

Abstract

Several bio-inspired underwater robots have been demonstrated in the last few years that can horizontally swim using different smart actuators. However, very few works have been presented on robots which can swim vertically, have a payload and resemble a jellyfish-like creature. In this work, we present the design, fabrication, and performance characterization of a new tethered robotic jellyfish, which is based on inflatable soft pneumatic composite (SPC) actuators. These soft actuators use compressed air to expand and contract, which help the robot to swim vertically in water. The soft actuators consist of elastomeric air chambers and very thin steel springs, which contribute to gaining faster motion of the biomimetic robot. A prototype of 220 mm in diameter and consisting of eight actuating units was fabricated and tested underwater in a fish tank. It reached a height of 400 mm within 2.5 s while carrying a dead weight of 100 g when tested at 70 psi (483 kPa) pressure. This high performance (160 mm/s on average speed) suggests that faster motion with a payload can be achieved by using SPC actuators. The inflatable structures help to flap the bell segments as well as in buoyancy effect for rapid vertical motion. The major achievement of this work is the ability to demonstrate a novel use of inflatable structures and biomimetic flapping wings for fast motion in water. The experimental and deduced data from this work can be used for the design of future small unmanned underwater vehicles (UUVs). This work adds a new robot to the design space of biomimetic jellyfish-like soft robots. Such kind of vehicle design might also be useful for transporting objects underwater effectively.

System‐Engineered Miniaturized Robots: From Structure to Intelligence

“…These living organisms generate propulsion force by traveling waves with an elastic tail or body driven by an oscillating head. [156] Microactuation in aquatic SEMRs has been demonstrated using on-board actuators, such as shape memory alloys, [157] hydraulic actuators, [158] dielectric elastomers, [159,160] hydrogels, [161] and liquid crystal elastomers, [162] which could be actuated by light, [161][162][163][164][165] heat, [9] or magnetic field, [166,167] allowing on-demand locomotion direction control. The jellyfishlike SEMR [168] was equipped with multiple functionalities in moderate-Reynolds number environment (Re % 7) (as shown in Figure 3a).…”

Kraken: a wirelessly controlled octopus-like hybrid robot utilizing stepper motors and fishing line artificial muscle for grasping underwater

“…A free-swimming jellyfish like robot was shown recently by Frames et al [18] using hydraulic actuation system. An inflatable soft pneumatic composite (SPC) actuators based jellyfish with payload was shown by Joshi et al [19]. Recently, an SMA jellyfish (Kryptojelly) is presented with unique features such as ease of varying the actuator parameters within the system and also multidirectional swimming [8].…”

Physical reservoir computing with origami and its application to robotic crawling

“…The animal kingdom is an endless source of inspiration for soft robotics 1 , 2 . Researchers have constructed compliant robots that can mimic all kinds of animal motions, like octopus locomotion 3 , elephant trunk grasping 4 , insect flying 5 , jellyfish and fish swimming 6 – 8 , as well as snake and insects crawling 9 – 11 . These robots share many similarities with animals regarding their shape and motion kinematics; however, their underlying sensing, actuation, and control architectures could be fundamentally different.…”