Imprecise Reliability Assessment for Heavy Numerical Control Machine Tools Against Small Sample Size Problem

• Published in: Shanghai jiao tong da xue xue bao Vol. 21; no. 5; pp. 605 - 610
• Main Author: 刘征 李彦锋 黄洪钟
• Format: Journal Article
• Language: English
• Published: Shanghai Shanghai Jiaotong University Press 01.10.2016; Springer Nature B.V
• Subjects: Architecture; Computer Science; Data processing; Electrical Engineering; Engineering; Life Sciences; Machine tools; Materials Science; Mathematical models; Numerical control; Numerical controls; Pricing policies; Probability theory; Reliability analysis; Reliability engineering; Uncertainty; reliability assessment; machine tool spindle; A; TG 502.1; natural extension model; empirical probability distribution
• ISSN: 1007-1172; 1995-8188
• DOI: 10.1007/s12204-016-1770-8

Small sample size problem is one of the main problems that heavy numerical control(NC) machine tools encounter in their reliability assessment. In order to deal with the small sample size problem, many indirect reliability data such as reliability data of similar products, expert opinion, and engineers’ experience are used in reliability assessment. However, the existing mathematical theories cannot simultaneously process the above reliability data of multiple types, and thus imprecise probability theory is introduced. Imprecise probability theory can simultaneously process multiple reliability data by quantifying multiple uncertainties(stochastic uncertainty,fuzzy uncertainty, epistemic uncertainty, etc.) together. Although imprecise probability theory has so many advantages, the existing natural extension models are complex and the computation result is imprecise. Therefore,they need some improvement for the better application of reliability engineering. This paper proposes an improved imprecise reliability assessment method by introducing empirical probability distributions to natural extension model, and the improved natural extension model is applied to the reliability assessment of heavy NC machine tool spindle to illustrate its effectiveness.