Design and material analysis for prototyping of four arm mechanical microgripper with self-locking and anti-slipping capability

Abstract

In this work, a mechanically actuated microgripper is designed with the COMSOL Multiphysics and its analysis is discussed. The mechanical microgripper is having a structure which consists of four arms which are held together with fingers emerging from a pedestal attached to the shaft where the input force is applied. The actuator is a screw based micrometer setup where self locking mechanism can be practiced. Based on the applied force, the initially closed gripper arms will be opened because of the force magnification acquired by the multiple stages and the fishbone structure of the gripper design. The study is done with the comparison between applied load versus the displacement achieved and also between the applied load and stress. As the design is displacement driven the studies performed is capable of representing the gripper’s real time working model. Various materials can be used for the gripper manufacturing, out of which aluminium, maraging steel, polycarbonate, verowhite and FullCure 720 are compared here and the best response is found to be aluminium in metals and polycarbonate in polymers. The prototyping can be done by rapid prototyping method, where the steps involved in the manufacturing of both polymer and metal grippers for various applications are discussed. The study is based on the structure’s stability because of the supporting fingers and the corresponding stress and displacement were also obtained.