Reliability-based analysis of machine structures using second-order reliability method

Abstract

In design and manufacture of machine structures and elements, the characteristics and sizes are randomly changing factors because of the change of loads, the mechanical properties of materials, and the quality of manufacturing process (size tolerances). Thus, the reliability of structures is extremely important to be considered carefully. This paper presents the application of Second-Order Reliability Method (SORM) to analyze and design of CNC milling machine structure. Many examples are utilized to validate the use of the proposed SORM approach. Then, the analytical findings are verified by comparing with First-Order Reliability Method (FORM) and Monte Carlo Method (MCS). The obtained findings highlighted that the SORM method is more reliable than the FORM method. Besides, the result deviations between the SORM method and the MCS method are negligible. Therefore, SORM method is a potentially effective approach in calculation and design with the aims of improving the reliability, increasing safety, and working efficiency of machine structures.