Comparison of displacement reconstruction methods by acceleration measurement

Abstract

A single degree of freedom system (SDOFS) consisting of a mass, a spring and a damper is used to clarify the advantages and disadvantages of the displacement reconstruction methods from measured acceleration, including high-pass filter method (HFM), frequency domain integration approach (FDIA), and joint input-state estimator (JISE). According to the noise ratio in the acceleration signal and the moving load characteristic on the system, included in the analyses are situations where (a) the maximum amplitude of measuring noise is 5% of the maximum amplitude of acceleration, and (b) the maximum amplitude of measuring noise is 10% of the maximum amplitude of acceleration, (c) the load on the system is a sinusoidal load with a mean of zero, (d) the load on the system is a offset sinusoidal load. Results show that (1) the displacement reconstructed by HFM has the characteristic of phase advance, and the displacement signal below the cut-off frequency is almost filtered; (2) FDIA has a good noise resistance, pseudo-static and low-frequency dynamic displacement also cannot be reconstructed from measured acceleration; (3) JISE can reconstruct complete displacement caused by moving load. However the method is more sensitive to noise than other methods, its performance decreases obviously with the increase of the noise ratio in the acceleration signal.