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FRF (Frequency Response Function)

Frequency Response Function

Biomechanics

Short definition

Response-to-excitation amplitude ratio as a function of frequency; in VibroTheory H(f) = A_hand(f)/A_hand(0).

Full definition

The FRF shows how many times the grip-zone vibration amplitude exceeds the quasi-static response to the same force pair: H → 1 as f → 0 and peaks near the assembly natural frequency with a height set by damping ζ. Combined with the hand amplitude it yields the dynamic hand force: F_hand_dyn = m_app · ω² · A_hand(f).

Examples

The H(f) peak at 45.5 Hz is the first resonance of the reference assembly.

Related terms

Кажущаяся масса кисти Частотный свип Собственная частота (мода) Демпфирование (ζ)