Magnetic actuation bionic robotic gripper with bistable morphing structure

Abstract

Soft robotics is an emerging research field that uses deformable materials or structures to fabricate compliant and adaptable systems through simple integrated mechanisms, thereby, enabling biomimetic behaviour. The Venus flytrap has the characteristics of excellent responsiveness and deformability, making it a promising inspirational model for the development of soft robotics. This paper presents a novel robotic gripper that mimics the trapping motion of the Venus flytrap. This gripper was implemented by exploiting a combination of bistable anti-symmetric shells and magnetic actuation. Two cylindrical shells constructed from carbon-fibre-reinforced polymer act as compliant fingers that can transform between two stable configurations based on external actuation. An applied clamped boundary condition reduces the actuation force required to trigger the morphing process. A novel non-contact magnetic actuation method with excellent responsiveness is proposed to actuate the compliant finger. The robotic gripper is designed to be lightweight and compact with high gripping force. Experiments and simulations were performed to analyse the gripping motion and measure the actuation force. The width of the clamped edge is the main factor influencing gripper performance as it relates to actuation force. The results of our analysis demonstrate that the proposed flytrap-inspired design with a bistable structure can be used to implement a novel robotic gripper controlled by a magnetic field.