A magnetic actuated deployable suction gripper for complex shaped surface attachment

Abstract

Suction grippers have the advantage to handle many different types and sizes of items, without being restricted by the dimensions of clamps to enclose an object and to handle objects more delicately.
However, the challenge of attaching these grippers to irregularly-shaped and rough surfaces remains a persistent issue. Despite advancements in research, the possibilities for miniaturisation, specific control, speed, and universal gripping capabilities still pose significant challenges. This study aims to overcome these obstacles by embedding magnetic intelligence within the material of a suction gripper and enabling the actuation of the attachment by an external magnetic field.
In this study, magnetic responsive soft materials are explored and different suction mechanisms are designed and validated to explore the opportunities of a magnetically actuated suction gripper. The miniaturisation options of the gripper are improved by implementing a compliant deploying mechanism. This results in the design of a magnetic actuated deployable suction gripper, using a thin magnetic membrane consisting of carbonyl iron particles in a silicone matrix material, in a frame of superelastic nitinol providing pressure on the rim and allowing for deploying.
A proof-of-principle prototype has been experimentally validated for attachment performance on a variety of curved surfaces in both dry and wet environments.
The attachment was achieved on curved surfaces with a radius of 50mm and 75mm, with a maximum attachment force of 2.89 \textpm 0.54 N. Observation suggests that only on surfaces with a curvature that is positioned exactly at the rim of the gripper attachment is not possible. For these surfaces, the nitinol wire rim prevented the flexible footprint membrane to seal onto the surface and leakage occurred.
The current gripper design is able to achieve a 75\% folding percentage, which allows it to enter hard-to-reach places in a small configuration while remaining enough surface area for attachment forces.
The proposed prototype serves as a foundation for further research in the development of reliable and effective magnetic-actuated suction grippers in a variety of configurations.