Design of a soft gripper with negative-pressure actuated synthetic annulus microwedge adhesive

Abstract

The automation and assembly lines of factories have faced the need for reliable handling of porous, fragile, and soft objects. Current soft grippers have difficulty robustly grasping flat, flexible surfaces without distorting them. This paper proposes a soft gripper based on annulus microwedge adhesive for grasping flat objects using negative pressure actuation mechanisms, which can achieve controllable adhesives to reliably grasp and easily release smooth flat objects. This is achieved through negative pressure actuation, which provides a centripetal load to the annular microwedge adhesives for strong attachment, by returning to normal pressure, the centripetal load is rapidly removed, allowing for easy detachment from the adhesive surface. Additionally, the relationship between the geometrical parameters of the deformation chamber and the contact area of annulus microwedges is investigated by using finite-element method models and experiments. The results show that the wall thickness is a key parameter in designing the deformation chamber. The results of the payload test have determined the geometrical and pressure parameters of the deformation chamber with the best adhesion performance. Finally, a demonstration shows that the gripper can handle various objects for potential applications, such as in clean environmental industries.

Keywords:

• Microwedge adhesives gecko adhesives negative-pressure actuation soft gripper

Authors’ contributions

Huimin Liu designed soft grippers, carried out the finite element analysis, conducted contact area measurement experiments, and wrote the manuscript; Jing Cui supervised the project, advised the design and experiments, and edited the manuscript; Xi Jin advised the finite element analysis and conducted experiments of grasping quality test; Jiejiang Su conducted repeatability and durability test and fabrication different size of the soft gripper; Zhongyi Chu acquisition of the financial support for the project leading to this publication and edited the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under Grant 52375006.