Investigation of damping characteristics on PLA robotic gripper fingers with magnetorheological fluid core and unimorph piezoelectric MFC

Abstract

AbstractPolylactic acid (PLA) is an environmentally friendly, biodegradable, and low‐cost thermoplastic material suitable for 3D printing. Complex shapes can be easily produced and hence PLA has been used for many applications. This study presents the damping characteristics of two robotic gripper fingers. The first gripper is composed of a PLA surface layer and a magnetorheological (MR) fluid core and the second gripper is composed of a PLA surface layer bonded to a surface of unimorph piezoelectric Macro Fiber Composite (MFC). The magnetic field is applied by using permanent magnets while the magnetic field strength is varied by changing the distance between the permanent magnets. The electric field is applied by using a micro‐amplifier and regulated using data acquisition systems. The natural frequency and damping ratio of the PLA gripper finger are determined by free vibration analysis using LabVIEW software. The damping ratio and vibration amplitude suppression for the PLA grippers was increased as the magnetic field strength changed from 0G to 600G (MR) and as the electric field changed from 0V to 360V (MFC).