Recently, Professor Xu Minyi's team from Dalian Maritime University proposed a three-dimensional biomimetic underwater triboelectric palm like tactile sensor (UPTS) based on liquid metal based friction nanogenerators for underwater robot grippers, aimed at accurately controlling the gripping force of underwater grippers. The sensor consists of a flexible cover, 5 independent sensing units, flexible support, and a 3D printed fixed shell. This paper conducted land and underwater experiments on UPTS, and the results of the land experiments showed that UPTS can accurately identify the magnitude, direction, and area of external force, with a positioning accuracy within 5 degrees, and can maintain stability even in high-frequency contact scenarios.

The results of underwater experiments show that UPTS can distinguish the hardness and shape of objects in water, with an accuracy rate of 100% for distinguishing the three hardness materials used in the experiment and a high accuracy rate of 99.75% for distinguishing the four shapes. The experimental results show that within a certain range, UPTS can not only monitor the real-time gripping force of the gripper, but also effectively distinguish the hardness and shape of the grasped object. This is of great significance for the gripping function of the gripper and provides more accurate data support for marine science research.