Alivaimennettu
Alivaimennettu is a Finnish term used to describe a system in which the damping is insufficient to prevent oscillatory motion after a disturbance. In a linear single-degree-of-freedom system described by m x'' + c x' + k x = f(t), the damping ratio is zeta = c / (2 sqrt(mk)). The system is underdamped when 0 < zeta < 1. The natural frequency is omega_n = sqrt(k/m) and the damped frequency is omega_d = omega_n sqrt(1 - zeta^2).
With a step or impulse input, an underdamped system responds with oscillations whose amplitude decays roughly
Applications and relevance: underdamped behavior is common in mechanical and structural engineering, such as vehicle suspensions,