Development of an automatic earring-post assembly system using an expert system approach

Document Type

Conference Proceeding

Date of Original Version



The problem of designing an automatic system to hand posts from bulk, to position them precisely and to weld them on findings, such a.s earrings, has been effectively solved by employing expert system methodologies and graph theory techniques. Design requirements are represented in terms of desired degree.s of freedom, desired type of motion, and the complexity of the mechanism in term.s of the number of independent loops. The expert system DOMES, Design of Mechanisms by an Expert System, developed at the University of Rhode Island, is employed to identify several kinematic structures of mechanism.s which fulfill all requirements. Present semi-automatic systems require an operator to handle and position findings and posts into a welding machine at rates of approximately sixty findings per minute. The developed system handles four hundred findings per minute. Results show that mechanism design techniques based on graph theory and expert systems are powerful tools for creative mechanism design. In this paper, emphasis is placed on the design of the mechanical system. However, the developed automatic earring-post assembly system includes several other features. A commercially available fusion welding machine is improved to attain rates of fourteen instead of three welds per second, a fifteen ton power press i,s integrated into the system and appropriate controls are designed and implemented together with light and acoustic sensors to synchronize the power press, the fusion welding equipment, and the post-handling equipment and to monitor system perfomiance on a real-time basis.

Publication Title, e.g., Journal

Proceedings of the ASME Design Engineering Technical Conference


Part F168016-6