Topology optimization to improve structural efficiency of 5000 lb over-center buckle

Abstract

Topology optimization for a considerable time has been successfully applied in the field of design for the development of light-weight structures. Especially in the aerospace sector, topology / topography optimization techniques are gaining recognition as effective tools for improving structural efficiency of newly designed aerospace vehicles. In that context, a study has been conducted on 5000 lb Over Center Buckle (OCB), which is one of the most commonly used tie down hardware to strap cargo in aircrafts. The aim of the research was to arrive at a light-weight design of the OCB without compromising on its strength and functional requirements. Key objective was to formulate a generally applicable methodology to assess and improve conventional designs of OCBs having different styles and capacities. Initially, various types of mechanical tests were conducted in accordance with SAE standard to identify the performance of commonly used 5000 lb OCB. Then a finite element model was developed and model validation was performed using experimental results. The tuned model served as a platform to carry out topology optimization where several design parameters were tested to assess their sensitivity and degree of influence for achieving higher structural efficiency. Finally, an alternative design was proposed for the existing 5000 lb OCB where 7% weight reduction could be achieved.