In a groundbreaking achievement, a team of researchers from Beihang University, in collaboration with the Institute of Deep-sea Science and Engineering of the Chinese Academy of Sciences and Zhejiang University, has developed an untethered miniature deep-sea robot weighing only 16 grams, capable of exploring the depths of the Mariana Trench. This remarkable feat marks a significant milestone in deep-sea exploration and robotics.
Release of the miniature deep-sea robot into the Mariana Trench (10,666 meters) in 2021
Robot crawling on the seafloor during deep-sea exploration
The study, titled “Miniature Deep-Sea Morphable Robot with Multimodal Locomotion,” was published on March 20 in the prestigious international journal Science Robotics, unveiling transformative potential for deep-sea exploration. The research was further spotlighted on the homepage of Science Robotics’ official website, showcased with a striking feature image, underscoring its significance in the field of robotics and ocean science.
Under the immense pressure of the deep sea, the modulus of flexible actuator materials increases, leading to a "stiffening" effect similar to that in muscles. This effect reduces the driving amplitude and speed, thereby diminishing the robot's operational performance.“The pressure at 10,000 meters is like having a small iceberg pressing down on a tiny robot,” explained Professor Wen Li, a leading researcher on the team.
To address this challenge, the team developed a novel deep-sea morphable robot, featuring a centimeter-scale soft actuator designed using chiral metamaterials and tube-sealed shape memory alloys (SMA). This innovative design leverages the increased modulus induced by hydrostatic pressure to achieve a higher snapping velocity, enhancing the actuator’s performance in extreme deep-sea conditions. The actuator is capable of performing undistorted cyclic motions at various depths, ensuring reliable operation in the harsh underwater environment.
What sets this robot apart is its ability to perform multimodal locomotion, including swimming, gliding, morphing, and crawling. It was deployed from deep-sea crewed submersibles and successfully demonstrated its capabilities at three distinct locations with varying depths: Haima Cold Seep (1,384 m), Longxi Seamount (3,756 m), and Mariana Trench (10,666 m). After completing its mission, the robot was retrieved fully intact, showcasing its robustness and durability.
Multimodal locomotion of the robot in the laboratory tank under atmospheric conditions
Multimodal locomotion of the robot in the deep sea
The research team also developed a wearable soft gripper based on the same metamaterial design strategy. This gripper, consisting of two symmetrical chiral units and a pair of grasping fingers, facilitates safe and efficient deep-sea operations, ranging from soft-specimen collection to heavy-object manipulation (~3400-meter depth).
Metamaterial soft gripper grasps starfish and sea cucumbers at a depth of 3,469 meters
The study not only highlights the potential of miniature deep-sea robots for future exploration but also provides valuable insights into creating next-generation miniature deep-sea actuators and robots. The successful deployment of this robot paves the way for future exploration and interaction with deep-sea ecosystems.
Pan Fei, Liu Jiaqi, Zuo Zonghao, and He Xia are the co-first authors of the paper, with Professors Wen Li and Ding Xilun serving as the corresponding authors. Beihang University is the first and corresponding affiliation of this paper. This work was supported by the National Science Foundation support projects and the National Key R&D Program of China.
Link to the article: https://www.science.org/doi/10.1126/scirobotics.adp7821
Editor: Lyu Xingyun
