Soft-Stable Interface in Grasping Multiple Objects by Wiring-tension

Efficiently manipulating objects in a group state is an emergent challenge for the soft robot hands. Overcoming this problem requires such hands to have highly stable structures to bear the heavy loads and highly compliant design to universally adapt to diverse object geometries. This study proposed a novel platform to develop the robot hands in manipulating multiple objects at each trial. In this scenario, the objects were in soft contact with an elastic wire mounted on the finger skeletons. This combination formed a harmonious hybrid finger that inherited both the soft flexible properties of the wire and the strong-stable bearing of the finger skeleton. One theoretical model was proposed to estimate the kinematics of manipulating multiple objects by the wiring-based fingers. Based on this model, we designed a hybrid gripper comprising two wiring-based fingers for conducting experimentally evaluations in manipulating four group samples: double bevel gears, double bevel gears plus pneumatic connector, double glue bottles, and double silicon bottles. The experimental results indicated that our proposed gripper reached good performance with high success rates in durability tests at different levels of the lifting velocity and high adaption with objects in soft-friendly interaction. These outcomes are potential to efficiently manipulate multiple complex objects per trial without requiring complicated controls.