Design of a Reconfigurable Gripper With Rigid-Flexible Variable Fingers

Grippers with a single rigid or flexible state have corresponding limitations, such as poor safety of rigid grippers and low precision of flexible grippers, which require complex algorithms and additional sensors to perform tedious tasks. Here, we design a reconfigurable gripper based on three fingers that can switch among the rigid, rigid bending, and flexible states. This adaptability enables the gripper to perform in diverse application scenarios. The flexible joints are locked and released by the back-and-forth movement of a slider mechanism, thus enabling switches between the rigid and flexible states of the fingers. When the fingers are in the rigid state, the structure resembles a conventional rigid gripper; when the fingers are in the flexible state, the spring-supported joints are driven by four cables. We have developed the mathematical models for the three states, tested the performance of different grasping configurations, analyzed the factors that influence horizontal grasping errors, and finally explored the application of rigid-flexible cooperative operations. Numerical and empirical experimental results clearly demonstrate the viability of the proposed gripper and its wide adaptability to different tasks.