Soft Robotics for Space Applications: Cryogenic Performance of Modular Metallic Cable Structures

Soft robotic systems are promising for diverse space applications due to their embedded compliance, promising locomotion methods, and efficient use of mass and volume. Space environments are harsher and more varied than those on Earth; extreme temperature, pressure, and radiation may impact the performance and robustness of soft robots. Cryogenic temperatures on celestial bodies such as the Moon or Europa pose significant challenges to the flexibility and actuation performance of conventional soft systems. We present a soft robotic design methodology using novel metallic-based soft robotic structures specifically tailored to extreme space environments. Structures are presented as tunable, reconfigurable modules for soft systems. Module behavior under compression is characterized while submerged in liquid nitrogen, and structural changes are investigated using scanning electron microscopy (SEM). The structures retained flexibility at −196 °C, with a limited 5% increase in peak stiffness over 100 cycles while maintaining a full range of motion. A soft robotic limb was constructed from these modules and demonstrated successful 2D manipulation and grasping of objects at −196 °C. SEM an