In a linear elastic structure, the displacement at one point caused by the application of a dynamic force at another point depends on the transfer function between the two points. The transfer function can be obtained at any given frequency by evaluating the response of the second point when a sinusoidal force of unit amplitude is applied at the first point. Once the transfer function has been obtained over a range of frequency the response at the second point to any dynamic force at the first point can be predicted. The term transfer function is sometimes used more generally to relate an input other than force (e.g. displacement) to an output other than displacement (e.g. velocity or acceleration).
Subjects: Noise & Vibration