A review on signal processing techniques utilized in the fault diagnosis of rolling element bearings

A review of stochastic resonance in rotating machine fault detection

A novel method is proposed for quantitative and localization diagnosis of a bearing outer ring defect in this paper. This method aims to distinguish these defects with different angular positions and different sizes based on the natural multiples of the ball angular spacing. Defects that differ in size by natural multiples of the ball angular spacing will have the same time interval, which may lead to misdiagnosis. Distinguishing such defects accurately is the goal for some industries. Therefore, the synchronized signal in the vertical and horizontal directions of the bearing systems with different angular positions and different size defects are quantitatively analyzed based on the presented five indices to explore the mechanism and method of distinguishing these defects. The simulation and experimental results show that the vertical–horizontal synchronized root mean square (VHSRMS) index can distinguish such defects effectively, and the defect angle position can be diagnosed using the VHSRMS–1 . More importantly, the VHS analysis method expands the location of the outer ring defect to 265–275° in quantitative diagnosis and realizes the localization diagnosis of the defect angle position. The research results provide a new approach and method for quantitative and localization diagnosis of a defective bearing.

Quantitative and Localization Diagnosis of a Defective Ball Bearing Based on Vertical–Horizontal Synchronization Signal Analysis

Vibration monitoring is one of the most effective ways for bearing fault diagnosis, and a challenge is how to accurately estimate bearing fault signals from noisy vibration signals. In this paper, a nonconvex sparse regularization method for bearing fault diagnosis is proposed based on the generalized minimax-concave (GMC) penalty, which maintains the convexity of the sparsity-regularized least squares cost function, and thus the global minimum can be solved by convex optimization algorithms. Furthermore, we introduce a k-sparsity strategy for the adaptive selection of the regularization parameter. The main advantage over conventional filtering methods is that GMC can better preserve the bearing fault signal while reducing the interference of noise and other components; thus, it can significantly improve the estimation accuracy of the bearing fault signal. A simulation study and two run-to-failure experiments verify the effectiveness of GMC in the diagnosis of localized faults in rolling bearings, and the comparison studies show that GMC provides more accurate estimation results than L1-norm regularization and spectral kurtosis.

Nonconvex Sparse Regularization and Convex Optimization for Bearing Fault Diagnosis

This paper intends to provide an overview on recent development of knowledge transfer for rotary machine fault diagnosis (RMFD) by using different transfer learning techniques. After brief introduction of parameter-based, instance-based, feature-based and relevance-based knowledge transfer, the applications of knowledge transfer in RMFD are summarized from four categories: transfer between multiple working conditions, transfer between multiple locations, transfer between multiple machines, and transfer between multiple fault types. Case studies on four datasets including gears, bearing, and motor faults verified effectiveness of knowledge transfer on improving diagnostic accuracy. Meanwhile, research trends on transfer learning in the field of RMFD are discussed.

Knowledge Transfer for Rotary Machine Fault Diagnosis

The sparse decomposition based on basic pursuit is an adaptive sparse expression of the signals. An adaptive basic pursuit algorithm that uses an impulse dictionary is introduced in this article for rolling bearing vibration signal processing and fault diagnosis. In the first, a new dictionary model is constructed according to the characteristics and mechanism of rolling bearing faults. Rotational speed of bearing, dimensions of bearing and bearing fault situation, among other parameters incorporates the new mode which could simulate the real fault impulse in different fault levels. Secondly a new method of dictionary establishment called adaptive impulse dictionary combine with basic pursuit introduced in this paper for bearing fault diagnosis. Adaptive impulse dictionary is created by changing characteristic parameters progressively, which make the dictionary built by this method has a lower redundancy and a higher relevance between each dictionary atom and the analyzed vibration signal. The basic pursuit algorithm of an adaptive impulse dictionary is adopted to analyze experiment signal of the early-stage fault signals and composite fault signals of the bearing. The results demonstrate the effectiveness of the basic pursuit algorithm that uses the adaptive impulse dictionary.

Basic pursuit of an adaptive impulse dictionary for bearing fault diagnosis

A small-sized electric brushed servo controller comprises a digit circuit, a power circuit and an isolating circuit. The digit circuit comprises a DSP chip, an FPGA, an AD chip, a power-on reset circuit I, an operational amplifier and a gate circuit I. The power circuit comprises an H-bridge module, an MOSFET drive module, a power-on reset circuit II, a gate circuit II and an MOSFET tube. The servo controller is designed for a brushed motor with large output torque, so that power drive cables of the motor is decreased, reliability is improved, and the small-sized requirement is met. A digital portion and a power portion are isolated in the hardware circuit design process so as to improve the working stability of the circuits. Except a motor driving function, the circuits further have an initiating explosive device timing sequence output function, and the servo working requirements of small-sized guided weapons are met.

Small-sized electric brushed servo controller

The invention discloses an aerodynamic configuration design method for a bi-rotational stable ball based on a fixed wing canard rudder. According to the method, after a rudder area SC, a pitching rudder angle setting value delta Z and the distance XC from a pressure center to a ball mass center of the fixed wing canard rudder are calculated respectively, the maximum value of the lift-to-drag ratio KL/D is solved according to formed constraint conditions; then, a rolling rudder angle setting value delta y and an empennage chamfer angle are determined according to internal and external friction moments of the fixed wing canard rudder and the moment balancing relation between an electromagnetic resistance moment and an aerodynamic moment; and the lift-to-drag ratio KL/D is adjusted under the condition that the rolling rudder angle setting value delta y and the empennage chamfer angle are determined to realize attitude adjustment of a mortar.

Chen Chang

Papers

Basic pursuit of an adaptive impulse dictionary for bearing fault diagnosis

Small-sized electric brushed servo controller

Aerodynamic configuration design method for bi-rotational stable ball based on fixed wing canard rudder