Vibration fatigue test and analysis methodology for flip chip solder joint fatigue life assessment have been developed by performing vibration tests with constant G-level and varying G-level input excitation. The linear cumulative damage analysis method (Miner’s rule) predicts non-conservative result for vibration fatigue life of flip chip solder joint. Finite element analysis (FEA) using a glo...

The methodology of vibration based condition monitoring technology has been developing at a rapid stage in the recent years suiting to the maintenance of sophisticated and complicated machines. The ability of wavelet analysis to efficiently detect non-stationary, non-periodic, transient features of the vibration signal makes it a demanding tool for condition monitoring. In this paper, the vibra...

Research on the nature of the vibration data collected from helicopter transmissions during flight experiments has led to several crucial observations believed to be responsible for the high rates of false alarms and missed detections in aircraft vibration monitoring systems. This work focuses on one such finding, namely, the need to consider additional sources of information about system vibra...

In order to obtain the useful information from the raw data which contain the state data reflecting the structure condition and the noise, de-noising and feature extraction techniques based on Wavelet analysis were studied. An improved wavelet thresholding algorithm to eliminate the noise for vibration signals was proposed. Comparison analysis with other thresholding algorithms shows that the n...

Piping vibration which is mainly caused by the torsional vibration of rotary compressor can be a major noise source of air-conditioner. Especially, the tangential vibration of rotary compressor which is due to the torsional vibration is much higher than the radial vibration or the vertical vibration of compressor. A study as to how the tangential vibration of rotary compressor is related with t...

In this study, the vibration and noise for the cushion frame that directly contacts the driver of the car are investigated. The friction noise from the seat track generating the largest noise is measured and analyzed. Also, vibration measurement and analysis are performed in parallel to locate the position from where the noise is generated. In the next stage, the RPM of motor and the current ch...

Gears are important element in a variety of industrial applications such as machine tool and gearboxes. An unexpected failure of the gear may cause significant economic losses. For that reason, fault diagnosis in gears has been the subject of intensive research. Vibration signal analysis has been widely used in the fault detection of rotation machinery. The vibration signal of a gearbox carries...

In this paper, a study on the characteristics and the reduction methods of ground vibration due to the tilting train travelling in the conventional line is carried out. The load transmitted into the ground is computed considering the interaction between the tilting car and the line. This load is then applied in the numerical model for the analysis of ground vibration due to the travelling tilti...

This paper reports the mechanical design, structural analysis, and experimental veri cation of a new high performance semi-direct drive robot arm. A design optimization methodology employing nite element analysis (FEA) is reviewed, and a resulting arm design is reported. FEA simulations of the nal design predict high structural vibration frequencies throughout the arms workspace. Extensive stru...

Rolling bearings are one of the most important noise and vibration generator into mechanical constructions. Therefore, it is very important to have knowledge of the rolling element bearings influence on the level of noise and vibration in this systems. This paper deals with a basic forms for generation of vibration and noise of rolling element bearing and suggestions of vibration analysis signi...