A new approach based on a linear Multi-Layer Perceptron for identifying on-line harmonics

2013 ◽  
Author(s):  
Thien Minh Nguyen ◽  
Patrice Wira
Keyword(s):  
Multi Layer Perceptron ◽  
New Approach ◽  
On Line

A New Approach to Machinery Monitoring and Diagnostics Using Self-Organizing Maps

1995 ◽  
Author(s):  
Siyu Zhang ◽  
R. Ganesan ◽  
T. S. Sankar
Keyword(s):  
Neural Network ◽  
Service Life ◽  
Trend Analysis ◽  
New Approach ◽  
Machine System ◽  
Network Algorithm ◽  
On Line ◽  
Neural Network Algorithm ◽  
Monitoring And Diagnostics ◽  
Self Organizing

Abstract The problem of estimating an unknown multivariate function from on-line vibration measurements, for determining the conditions of a machine system and for estimating its service life is considered. This problem is formulated into a multiple-index based trend analysis problem and the corresponding indices for trend analysis are extracted from the on-line vibration data. Selection of these indices is based on the simultaneous consideration of commonly-observed faults or malfunctions in the machine system being monitored. A neural network algorithm that has been developed by the present authors for multiple-index based regression is adapted to perform the trend analysis of a machine system. Applications of this neural network algorithm to the condition monitoring and life estimation of both a bearing system as well as a gearbox are fully demonstrated. The efficiency and computational supremacy of the new algorithm are established through comparing with the performance of Self-Organizing Mapping (SOM) and Constrained Topological Mapping (CTM) algorithms. Further, the usefulness of multiple-index based trend analysis in precisely predicting the condition and service life of a machine system is clearly demonstrated. Using on-line vibration signal to constitute the set of variables for trend analysis, and employing the newly-developed self-organizing neural algorithm for performing the trend analysis, a new approach is developed for machinery monitoring and diagnostics.

Improving the Accuracy of Multi-Axis Machines Through On-Line Error Compensation Using Neural Networks

1998 ◽  
Author(s):  
Abderrazak El Ouafi ◽  
Michel Guillot ◽  
Abdellah Bedrouni
Keyword(s):  
Error Compensation ◽  
Error Modeling ◽  
Precision Engineering ◽  
Dimensional Error ◽  
New Approach ◽  
Turning Center ◽  
On Line ◽  
Dynamic Errors ◽  
Compensation Approach ◽  
Compensation Function

Abstract This research is devoted to one of the most fundamental problems in precision engineering: multi-axis machines accuracy. The paper presents a new approach designed to support the implementation of software error compensation of geometric, thermal and dynamic errors for enhancing the accuracy of multi-axis machines. The accuracy of multi-axis machines can be significantly improved using an intelligent integration of sensor information to perform the compensation function. The compensation process consists of the following major steps carried out on-line: continuous monitoring of the machine conditions using position, force, speed and temperature sensors mounted on the machine structure. Error forecasting through sensor fusion. Volumetric error synthesis and software compensation. To improve the effectiveness of error modeling, an artificial neural network is extensively applied. Implemented on a turning center, the compensation approach has enabled improvement of the machine accuracy by reducing the maximum dimensional error from 70 μm initially to less than 4 μm.

A New Approach to the Experimental Study of Turbomachinery Flow Phenomena

1977 ◽  
Vol 99 (1) ◽  
pp. 97-105 ◽  
Author(s):  
J. P. Gostelow
Keyword(s):  
Flow Field ◽  
Unsteady Flow ◽  
Axial Flow ◽  
Centrifugal Pumps ◽  
New Approach ◽  
Static Pressure Distribution ◽  
Compressor Rotor ◽  
Flow Phenomena ◽  
On Line ◽  
Flow Compressor

Measurements of the unsteady flow field over a rotor and within its wake are needed in the development of most turbomachines. The technique advocated is that of data acquisition by on-line computer, using the periodic passing of a blade as a phase reference. The phase-lock averaging process is described as is its use in reducing the noise of raw data traces. Measurements of the unsteady flow over a cascade and of the resulting boundary layer behavior are presented. The approach was used in interpreting the unsteady flow field of an axial-flow compressor rotor and the static pressure distribution over the rotor tip. Finally the application to centrifugal pumps is discussed, enabling the designer to obtain information on the suction pressures and the extent of any separated region.

“On line” collection quality of life (QL) items in the oncological hospital at home (OHH): A new approach

1993 ◽  
Vol 29 ◽  
pp. S215
Author(s):  
S. Glordani ◽  
C. Frenquelli ◽  
V. Paletta ◽  
S. Salvagni ◽  
F. Pannuti
Keyword(s):  
Quality Of Life ◽  
New Approach ◽  
On Line ◽  
Hospital At Home ◽  
At Home

A Measurement and Analysis Technique of Curves of Metal Parts

2012 ◽  
Vol 424-425 ◽  
pp. 665-668
Author(s):  
Wei Shao ◽  
Deng Xin Hua
Keyword(s):  
Error Analysis ◽  
Shape Matching ◽  
Mathematic Model ◽  
New Approach ◽  
Great Volume ◽  
Metal Parts ◽  
Analysis Technique ◽  
Measurement And Analysis ◽  
On Line ◽  
Implicit Polynomials

Metal parts with large and complicated curved surfaces used widely have some characteristics such as a great volume, a big area, distorting easily. It is very difficult to measure and evaluate accurately the parts. Taking measurement of the parts as a purpose, a new measurement method called On-Line Shape Measurement System (OSMS) is put forward.Error analysis of curves is a requirement to assure quality and to reduce manufacturing costs and rework. This paper proposes a new approach and algorithms for the error analysis of curves.the system applies a robust mathematic model, Implicit polynomials (IP), to construct the model of the test-points. Once the CAD model is adjusted, it is compared with input to reveal the errors between their shapes. To accomplish this task a new shape matching algorithm is developed. Experimental results on error analysis of a variety of the machined metal skin of aircraft are reported to show the validity of the proposed methodology.

Sign in / Sign up

Export Citation Format

Share Document