Time and frequency domain analyses of single-degree-of-freedom systems

Time and frequency domain analysis methods for calculating the relative displacement and velocity responses of single-degree-of-freedom systems are examined. Various problems associated with both methods are discussed and solutions to the problems are presented for oscillators with low to high frequencies. Straight-line interpolation of the forcing function in time domain analysis introduces frequencies that are greater than the Nyquist frequency, leading to an inaccurate relative velocity response for the high (greater than the Nyquist) frequency oscillators. One method of avoiding this problem is to use higher order interpolation functions. As an alternative, a frequency domain analysis method is presented.