Vibrational analysis accelerometers

Workers involved in the activity of semi-mechanized tillage were exposed to hands and arms vibration. For vibration analysis the MAESTRO instrument manufactured by OldB coupled to a triaxial accelerometer was fixed at the point where energy was transmitted to the hands. This instrument provides the values of the magnitude of acceleration in ms-2 in the weighted frequencies from 6.3 to 1250 Hz. Digging holes machines brand Stihl BT 121 model were evaluated using the Directive 2002/44/EC the European Community (EUROPEAN PARLIAMENT AND OF THE COUNCIL, 2002). The values set by the Directive for hand and arm are 2.5 m s" to alert level and 5.0 m s to threshold level. 

The monitoring of turbomachinery mechanical characteristics, such as vibrations, has been applied extensively over the past decade. The advent of the accelerometer and the real-time vibration spectrum analyzer has required a computer to match and utilize the extensive analysis and diagnostic capability of these instruments. 

Leaks in process vessels and devices such as valves are a serious problem in many industries. A variation of vibration monitoring and analysis can be used to detect leakage and isolate its source. Leak-detection systems use an accelerometer attached to the exterior of a process pipe. This allows the vibration profile to be monitored in order to detect the unique frequencies generated by flow or leakage. 

Vibration can cause problems to the human body, machines and structures, as well as producing high noise levels. It is commonly measured using an accelerometer which can indicate a value in terms of acceleration, velocity or displacement. There are many types of accelerometer and associated instrumentation available which can give an analogue or digital readout or can be fed into a computerised analysis system. As with sotmd, the vibration component would be measured at particular frequencies or over a band of frequencies. 

The pump failure can be associated with wear that can cause unbalancing and consequently mains shaft vibration. The use of accelerometers as vibration transducers allows the use of condition-based monitoring of the pump. Also, ultrasound analysis can be applied for detection of cavitation at the pump. 

Spatial and temporal strain data contain rich information about the monitored system. However, the task of condition assessment cannot be successfully conducted without the extraction of meaningful features from data. The problem is analogous to signals from accelerometers from which, in most cases, frequency features (e.g., fundamental frequencies, mode shapes) need to be extracted to enable the analysis of the vibration signature. Several types of features can be extracted from an array of strain gauges,... 

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