Design of a novel dexterous robotic gripper for in-hand twisting and positioning within assembly automation

Abstract

Purpose – This paper aims to design a novel jaw gripper with human-sized anthropomorphic features to be suitable for precise in-hand posture transitions, such as twisting and re-positioning. The growing demand from traditional high-mix low-volume and new massive customized manufacturing industry requires the robot with configurability and flexibility. In the electronic manufacturing industry particularly, the design of the robotic hand with sufficient dexterity and configuration is important for the robot to accomplish the assembly task reliably and robustly. It is important for the robot to be able to grasp and manipulate a large number of assembly parts or tools. Design/methodology/approach – In this research, a novel jaw-like gripper with human-sized anthropomorphic features is designed for online in-hand precise positioning and twisting. It retains the simplicity feature of traditional industrial grippers and dexterity features of dexterous robotic hands. Findings – The gripper is able to apply suitable gripping force on assembly parts and performs reliable twisting movement within limited time to meet the industrial requirements. Manipulating several cylindrical assembly parts by robot, as an experimental case in this paper, is studied to evaluate its performance. The effectiveness of proposed gripper design and mechanical analysis is proved by the simulation and experimental results. Originality/value – The main originality of this research is that a novel jaw gripper with human-sized anthropomorphic features is designed to be suitable for precise in-hand posture transitions, such as twisting and re-positioning. With this gripper, the robotic system will be sufficiently flexible to deal with various assembly tasks.

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