Frequency Domain Nonlinear Vibration Features for Fault Diagnosis in Complex Structures

This book provides a comprehensive introduction to recent advances in frequency domain nonlinear vibration features utilized for fault diagnosis in complex structures in the field of mechanical, civil, aeronautical and aerospace engineering. It illustrates their basic principles, advantages, drawbacks and applications in detail through theoretical analysis and simulation/experimental study.

This book focuses on frequency domain nonlinear vibration features and its main contents can be classified into two parts according to the introduced features. One is about features based on the SOOS (second-order output spectrum), and the other is about features based on the OS@DF (output spectrum at the double frequency or the second harmonic frequency). Complex structures in this book include satellites, aeroengines, bridges, pipelines, frames, etc., and corresponding multiple degree-of-freedom (MDOF) models include chain-type, beam-type, ring-like, grid-like, unit-like and rotating models.

Detailed theoretical analysis and case demonstration help undergraduates, graduates and researchers have a systematical learning process and understand basic dynamic characteristics of complex structures more thoroughly. Then, some models, methods and results in this book can be a valid reference for the design, optimization and iteration of next-generation complex structures. On the other hand, this book provides a totally new inspiration for fault diagnosis methods combined with artificial intelligence and machine learning algorithms since frequency domain nonlinear vibration features introduced in this book are more sensitive and effective to faults.

Introduction.- Representation of Complex Structures with the Volterra Series.- Utilising Properties of SOOS TFs to Virtual Beam-like Structures.- A Novel Method based on SOOS TFs and Local Tuning Approach.- An Improved Method based on SOOS TFs for Ring-type Structures.- A Systematic Method based on SOOS TFs for Various Types of Faults.- A Novel OS@DF TF-based Method for Open Beam-type Structures.- A Novel OS@DF TF-based Method for Closed Ring-type Structures.- A Novel OS@DF TF-based Method for Simple Grid-type Structures.- An Integrated OS@DF TF-based Method for Union-type Structures.- One Extended OS@DF TF-based Method for Rotor-type Structures.- Summary and Overview.

Dr. Quankun Li received his B.Eng. degree from Nanjing University of Aeronautics and Astronautics, China, in 2011, M.Eng. degree in Propulsion Theory and Engineering of Aeronautics and Astronautics from Northwestern Polytechnical University, China, in 2014, and Ph.D. degree in Mechanical Engineering from Hong Kong Polytechnic University, China, in 2020, respectively. He is now Associate Professor with the School of Power and Energy, Northwestern Polytechnical University, and his current research topic is the Vibration Control and Fault Diagnosis of mechanical structures including satellites, engines, aircrafts, vehicles, etc. He currently serves as Guest Associate Editor on Vibration Systems of Frontiers in Mechanical Engineering, Reviewer Editor on Energetics and Propulsion of Frontiers in Aerospace Engineering, and Section collection Editor on Vibration Systems of Mechanical Engineering Advances.

Prof. Xingjian Jing received his B.S. degree from Zhejiang University, China, M.S. degree and Ph.D. degree in Robotics from Shenyang Institute of Automation, Chinese Academy of Sciences, China, respectively. He also achieved a Ph.D. degree in nonlinear systems and signal processing from University of Sheffield, U.K. He is now Professor with the Department of Mechanical Engineering, City University of Hong Kong, and his current research interests are generally related to Nonlinear Dynamics, Vibration, Control and Robots, focusing on theory and methods for employing nonlinear benefits in engineering, including nonlinear frequency domain methods, nonlinear system identification or signal processing, vibration control, robust control, sensor technology, energy harvesting, nonlinear fault diagnosis or information processing, bio-inspired systems and methods, bio-inspired robotics and control, etc.