Design and Manufacturing of a Lead Screw Robotic Gripper

Abstract

Robotic grippers have many amazing uses. From helping to rescue trapped animals underwater to holding surgical tools in precise locations during an operation, robotic grippers have proved to be useful for many functions that are tedious, dangerous and difficult for the human hand to perform. The MIT MRL needs a robotic gripper to attach to a rotating shaft for a current project that is being worked on. The addition of this gripper as an end effector to the system can provide unique data that will be informative for real world mechanical systems. This thesis provides a review of a range of different robotic grippers through their history and explains the uses of different robotic gripper and have they have developed over time. Looking at two specific case studies the paper collects advantages and drawbacks of the two grippers and identifies the most important factors to take into account when designing a gripper.

Using this information, a gear operated gripper is designed and its features are briefly discussed. Based on the drawbacks of the original gripper design a lead screw gripper is designed and then a prototype is manufactured. The process of manufacturing found that the gripper can be assembled by hand, it is strong and articulates smoothly. The drawbacks with the design are mainly from the size of the body and the difficulty with press-fitting between a 3mm aluminum shaft and its bearing. The prototype worked effectively to grip the shaft; however, the gripper could be improved in order to be stronger and articulate even smoother.