Soil Dynamics by Dr. Deepankar Choudhury, Department of Civil Engineering, IIT Bombay. Mod Lec Transmissibility is the ratio of output to input. Transmissibility: means amplification and maximum amplification occurs when forcing frequency and natural frequency of the system coincide. There is no unit designation for transmissibility, although it may sometimes be referred to as the Q factor. Transmissibility. Transmissibility. Assuming that the forcing function is harmonic in nature, we shall consider two cases of vibration transmission - one in which force is transmitted to the supporting structure, and one in which the motion of the supporting structure is transmitted to the machine. (a) Force excitation.
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Fundamentals of Vibration
See other articles in PMC that cite the published article. Abstract The objective of this study is to enhance the understanding of the vibration transmission in the hand-arm system in three orthogonal directions X, Y, and Z.
For the first time, the transmitted vibrations distributed on the entire transmissibility vibration system exposed in the three orthogonal directions via a 3-D vibration test system were measured using a 3-D laser transmissibility vibration.
Seven adult male subjects participated in the experiment. This study confirms that the vibration transmissibility generally decreased with the increase transmissibility vibration distance from the hand and it varied with the vibration direction.
Transmissibility (vibration) - Wikipedia
Specifically, to the upper arm and shoulder, only moderate vibration transmission was measured in the test frequency range 16 to Hzand virtually no transmission was measured in the frequency range higher transmissibility vibration 50 Hz.
The resonance vibration on the forearm was primarily in the range of 16—30 Hz with the peak amplitude of approximately 1.
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The major resonance on the dorsal surfaces of the hand and wrist occurred at around 30—40 Hz and, in the Transmissibility vibration direction, with peak amplitude of more than 2.
At higher than 50 Hz, vibration transmission was effectively limited to the hand and fingers. A major finger resonance was observed at around Hz in the X and Y directions and around Hz in the Z direction.
In the fingers, the resonance magnitude in the Z direction was generally the lowest, and the resonance magnitude in transmissibility vibration Y direction was generally the highest with the resonance amplitude of 3 times the input vibration, which was similar to the transmissibility at the transmissibility vibration and hand dorsum.
The implications of the results are discussed. Relevance to industry Prolonged, intensive exposure to hand-transmitted vibration could result in hand-arm vibration syndrome.
While the syndrome's precise mechanisms remain unclear, the characterization of the vibration transmissibility of the system in the three orthogonal dimensions performed in this study transmissibility vibration help understand the syndrome and help develop improved frequency weightings for assessing the risk of the exposure for developing various components of the syndrome.
Hand-arm vibration transmissibility, Hand-transmitted vibration, Human-arm vibration, Vibration biodynamic response 1.
Although many studies on this subject have been reported, the syndrome's precise mechanisms remain unclear ISO One of the essential foundations for transmissibility vibration understanding their mechanisms is the biodynamic responses of the hand-arm system to vibration Griffin, ; Dong et al.
Because the transmissibility on the human body is directly measurable, it can be used to represent the distributed features of the system responses, and it has a certain relationship with the driving-point response function Dong et al. It remains a challenging task to accurately measure the transmitted vibration on the hand-arm system of a subject.
The attachment of an accelerometer to the skin usually introduces some artificial constraints to the local structure where the vibration is measured. The mass of the accelerometer could also significantly affect the measurement results.
The equation that describes the dynamics of the system is: Therefore, it would appear that the engineering principles employed to protect the supporting structure under force excitation are the same transmissibility vibration those used to protect the dynamic system from motion excitation.