A bioinspired shape memory alloy based soft robotic system for deep-sea exploration

Abstract

Developing robots integrating sensors, actuators, and computational capabilities for deep-sea exploration is challenging. Nature often offers innovative solutions to complex problems, and in this context, inspiration is drawn from the remarkable abilities of deep-sea snails, specifically their unique tentacles, often referred to as “eyestalks” due to the presence of an eye at their tip. Herein, “DeepStalk,” a soft robot designed for deep-sea exploration, is introduced, utilizing three shape memory alloys (SMAs) springs that mimic the three tentacle flexor muscles of deep-sea snails. Overall, DeepStalk incorporates sensory, actuation, and control modules for operation under high hydrostatic pressure. To achieve precise control of its orientation in 3D space, a simple and reliable vector-PID controller is developed. Remarkably, the robot successfully maintains its desired bending attitude even at 30 MPa hydrostatic pressure, achieved through the Joule heating of SMA springs. Furthermore, DeepStalk demonstrates the capability to track moving objects underwater, showcasing its potential application in challenging environments at depths of up to 20 MPa. This marks the first attempt for soft robots to integrate sensor, actuator, and control modules capable of complex tasks under high hydrostatic pressure. This innovative research advances integrated soft robotic systems for deep-sea exploration field.