Non-linear system identification of gear crack failure based on second order Volterra kernel

Abstract

Non-linear system identification has attracted great interest in mechanical fields. Against the weak vibration signals of gear crack failure and the considerable but ignored influence by input variation in gear tooth system non-linear working condition, which put forward a huge challenge to gear crack failure detection and identification's accurate, we have proposed a new non-linear non-parameter method that used the second order Volterra kernel function to analyse the inner contact between crack failure and the corresponding non-linear changes in whole system term. After identifying gear tooth system second order kernel function with input and output time series, we analysed the non-linear information indicated by frequency spectrum in detail. Anglicisation and comparison results show that gear tooth crack failure's second order Volterra kernel function considered the fault identification's correction influenced by input elements and was sensitive to system non-linear changes which were caused by different fault conditions. And, this non-linear system identification method can solve the diagnosis' fuzziness and indeterminacy problems caused by traditional frequency sideband theory. This new method is also helpful for mechanical system modelling, security running monitoring, dynamic design, the study of dynamic characteristics, and the fault diagnosis of rotary systems.