In any industry,it is the requirement to know whether the machine is healthy or not to operate machine further.If the machine is not healthy then what is the fault in the machine and then finally its location.The pape...In any industry,it is the requirement to know whether the machine is healthy or not to operate machine further.If the machine is not healthy then what is the fault in the machine and then finally its location.The paper is proposing a 3-Steps methodology for the machine fault diagnosis to meet the industrial requirements to aid the maintenance activity.The Step-1 identifies whether machine is healthy or faulty,then Step-2 detect the type of defect and finally its location in Step-3.This method is extended further from the earlier study on the 2-Steps method for the rotor defects only to the 3-Steps methodology to both rotor and bearing defects.The method uses the optimised vibration parameters and a simple Artificial Neural Network(ANN)-based Machine Learning(ML)model from the earlier studies.The model is initially developed,tested and validated on an experimental rotating rig operating at a speed above 1st critical speed.The proposed method and model are then further validated at 2 different operating speeds,one below 1st critical speed and other above 2nd critical speed.The machine dynamics are expected to be significantly different at these speeds.This highlights the robustness of the proposed 3-Steps method.展开更多
A new type of vibration structure (i.e. supporting system, called swing frame cus- tomarily) of vertical dynamic balancing machine has been designed, which is based on an analysis for the swing frame of a traditiona...A new type of vibration structure (i.e. supporting system, called swing frame cus- tomarily) of vertical dynamic balancing machine has been designed, which is based on an analysis for the swing frame of a traditional double-plane vertical dynamic balancing machine. The static unbalance and couple unbalance can be e?ectively separated by using the new dynamic balancing machine with the new swing frame. By building the dynamics model, the advantages of the new structure are discussed in detail. The modal and harmonic response are analyzed by using the ANSYS7.0. By comparing the ?nite element modal analysis with the experimental modal analy- sis, the natural frequencies and vibration modes are found. There are many spring boards in the new swing frame. Their sti?nesses are di?erent and assorted with each other. Furthermore, there are three sensors on the measuring points. Therefore, the new dynamic balancing machine can measure static unbalance and coupling unbalance directly, and the interaction between them is faint. The result shows that the new vertical dynamic balancing machine is suitable for inertial measurement of ?ying objects, and can overcome the shortcomings of traditional double-plane vertical dynamic balancing machines, which the e?ect of plane-separation is inferior. The vertical dynamic balancing machine with the new vibration structure can ?nd wide application in the future. The modelling and analysis of the new vibration structure will provide theoretical basis and practical experience for designing new-type vertical dynamic balancing machines.展开更多
To ameliorate reliability analysis efficiency for aeroengine components, such as compressor blade, support vector machine response surface method(SRSM) is proposed. SRSM integrates the advantages of support vector mac...To ameliorate reliability analysis efficiency for aeroengine components, such as compressor blade, support vector machine response surface method(SRSM) is proposed. SRSM integrates the advantages of support vector machine(SVM) and traditional response surface method(RSM), and utilizes experimental samples to construct a suitable response surface function(RSF) to replace the complicated and abstract finite element model. Moreover, the randomness of material parameters, structural dimension and operating condition are considered during extracting data so that the response surface function is more agreeable to the practical model. The results indicate that based on the same experimental data, SRSM has come closer than RSM reliability to approximating Monte Carlo method(MCM); while SRSM(17.296 s) needs far less running time than MCM(10958 s) and RSM(9840 s). Therefore,under the same simulation conditions, SRSM has the largest analysis efficiency, and can be considered a feasible and valid method to analyze structural reliability.展开更多
XY table automated assembly machines ensure time saving and quality improving in the electronics industry. Recently, due to the need of higher operation speeds and lighter machines in PCB （Printed Circuit Board） ass...XY table automated assembly machines ensure time saving and quality improving in the electronics industry. Recently, due to the need of higher operation speeds and lighter machines in PCB （Printed Circuit Board） assembly, a challenging problem has arisen which is the table positioning vibration. The high speed with the machine flexibility, make the positioning vibration inevitable although the inner control. The positioning vibration is to be reduced otherwise the machine becomes useless. Firstly, the machine is modeled, the positioning vibration is formulated, and then analyzed. Secondly, using the analysis, three direct control methods are identified to decrease the positioning vibration, they are based on the kinematics, dynamics, and operation of the machine. Thirdly, the methods are examined numerically to evaluate their efficiency. Lastly, the identified methods are discussed to conclude on their application. The results are a real contribution in the vibration control of XY table automated assembly machines, which is classified as industrial knowhow.展开更多
Electrical machines are precarious mechanisms in manufacturing practices. A motor failure may yield an unexpected interruption at the industrial plant, with consequences in costs, product quality, and security. To gov...Electrical machines are precarious mechanisms in manufacturing practices. A motor failure may yield an unexpected interruption at the industrial plant, with consequences in costs, product quality, and security. To govern the conditions of each part of motor, various testing and monitoring methods have been developed. In this paper, a review on effective fault indicators and vibration based condition monitoring approaches of rotating electrical machines has been accomplished. The determination of the review is to progress the understanding of vibration based analysis, and its use in the Machine Health Monitoring. A variety of analysis was identified to highlight the concept of predictive maintenance in industries. The techniques of vibration analysis were investigated to detect both healthy and fault related signals of rotating machineries.展开更多
文摘In any industry,it is the requirement to know whether the machine is healthy or not to operate machine further.If the machine is not healthy then what is the fault in the machine and then finally its location.The paper is proposing a 3-Steps methodology for the machine fault diagnosis to meet the industrial requirements to aid the maintenance activity.The Step-1 identifies whether machine is healthy or faulty,then Step-2 detect the type of defect and finally its location in Step-3.This method is extended further from the earlier study on the 2-Steps method for the rotor defects only to the 3-Steps methodology to both rotor and bearing defects.The method uses the optimised vibration parameters and a simple Artificial Neural Network(ANN)-based Machine Learning(ML)model from the earlier studies.The model is initially developed,tested and validated on an experimental rotating rig operating at a speed above 1st critical speed.The proposed method and model are then further validated at 2 different operating speeds,one below 1st critical speed and other above 2nd critical speed.The machine dynamics are expected to be significantly different at these speeds.This highlights the robustness of the proposed 3-Steps method.
基金Project supported by the National Natural Science Foundation of China (No.10176011).
文摘A new type of vibration structure (i.e. supporting system, called swing frame cus- tomarily) of vertical dynamic balancing machine has been designed, which is based on an analysis for the swing frame of a traditional double-plane vertical dynamic balancing machine. The static unbalance and couple unbalance can be e?ectively separated by using the new dynamic balancing machine with the new swing frame. By building the dynamics model, the advantages of the new structure are discussed in detail. The modal and harmonic response are analyzed by using the ANSYS7.0. By comparing the ?nite element modal analysis with the experimental modal analy- sis, the natural frequencies and vibration modes are found. There are many spring boards in the new swing frame. Their sti?nesses are di?erent and assorted with each other. Furthermore, there are three sensors on the measuring points. Therefore, the new dynamic balancing machine can measure static unbalance and coupling unbalance directly, and the interaction between them is faint. The result shows that the new vertical dynamic balancing machine is suitable for inertial measurement of ?ying objects, and can overcome the shortcomings of traditional double-plane vertical dynamic balancing machines, which the e?ect of plane-separation is inferior. The vertical dynamic balancing machine with the new vibration structure can ?nd wide application in the future. The modelling and analysis of the new vibration structure will provide theoretical basis and practical experience for designing new-type vertical dynamic balancing machines.
基金Project(51335003)supported by the National Natural Science Foundation of ChinaProject(20111102110011)supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘To ameliorate reliability analysis efficiency for aeroengine components, such as compressor blade, support vector machine response surface method(SRSM) is proposed. SRSM integrates the advantages of support vector machine(SVM) and traditional response surface method(RSM), and utilizes experimental samples to construct a suitable response surface function(RSF) to replace the complicated and abstract finite element model. Moreover, the randomness of material parameters, structural dimension and operating condition are considered during extracting data so that the response surface function is more agreeable to the practical model. The results indicate that based on the same experimental data, SRSM has come closer than RSM reliability to approximating Monte Carlo method(MCM); while SRSM(17.296 s) needs far less running time than MCM(10958 s) and RSM(9840 s). Therefore,under the same simulation conditions, SRSM has the largest analysis efficiency, and can be considered a feasible and valid method to analyze structural reliability.
文摘XY table automated assembly machines ensure time saving and quality improving in the electronics industry. Recently, due to the need of higher operation speeds and lighter machines in PCB （Printed Circuit Board） assembly, a challenging problem has arisen which is the table positioning vibration. The high speed with the machine flexibility, make the positioning vibration inevitable although the inner control. The positioning vibration is to be reduced otherwise the machine becomes useless. Firstly, the machine is modeled, the positioning vibration is formulated, and then analyzed. Secondly, using the analysis, three direct control methods are identified to decrease the positioning vibration, they are based on the kinematics, dynamics, and operation of the machine. Thirdly, the methods are examined numerically to evaluate their efficiency. Lastly, the identified methods are discussed to conclude on their application. The results are a real contribution in the vibration control of XY table automated assembly machines, which is classified as industrial knowhow.
文摘Electrical machines are precarious mechanisms in manufacturing practices. A motor failure may yield an unexpected interruption at the industrial plant, with consequences in costs, product quality, and security. To govern the conditions of each part of motor, various testing and monitoring methods have been developed. In this paper, a review on effective fault indicators and vibration based condition monitoring approaches of rotating electrical machines has been accomplished. The determination of the review is to progress the understanding of vibration based analysis, and its use in the Machine Health Monitoring. A variety of analysis was identified to highlight the concept of predictive maintenance in industries. The techniques of vibration analysis were investigated to detect both healthy and fault related signals of rotating machineries.
