J0450403 Identification Accuracy Evaluation of Natural Frequency for Smart Washer by Adopting Variable Gain Type Adaptive Observer
J0450403 可変ゲイン型適応オブザーバによるスマートワッシャの固有振動数同定精度の評価([J045-04]知的材料・構造システム(4),機械材料・材料加工部門)

Hitoshi ITO, Masayuki OKUGAWA
2014 The Proceedings of Mechanical Engineering Congress Japan  
Bolted joints are widely used in mechanical and architectural structures . However , many serious accidents occur because of loosening in bolted joints , The diagnosis of the bolt loosening is able to be achieved by evaluating the variation of tightening axial tension . Conventionally , the inspection method of the loosening bolted joint is generally the measurement of the axial tension of a bolted joint by using ultrasonic waves . These methods require the use of special measurement equipment
more » ... nd . the human operation 」 n this study , a smart washer was proposed to detect the loosening without human involvement. The basic principle of how to deteot bolt loosenlng is to the dynamics characteristics of a smart washer system which varies depending on bolt tightening axial tension . A novel bolt loosening detection method by adaptive observer with variable gain is proposed in this paper. The numerical simulations are perfbmled to verif シ the possibility ofthe adaptive observer − based loosening detection .
doi:10.1299/jsmemecj.2014._j0450403- fatcat:njaeum3i2bcgjc73ju4hzdmlk4