Abstract—In the application of pavement roughness test, accelerometer sensors are used to measure vertical acceleration of a vehicle body. The displacement of that object is then determined by using double integrating acceleration data from the accelerometer sensor. High pass filters are used to remove DC components to avoid integrated errors. Fast Fourier Transform (FFT) Filter is known to provide a higher accuracy compared to Infinite Impulse Response (IIR) Filter and Finite Impulse Response (FIR) Filter. In this research, we analyze the performance of FFT Filter with experiment in MATLAB. The results show that FFT filters give results more accurate than do FIR and IIR not only for single frequency signal but also for multi-frequency signal. The standard error and peak error of FFT Filter are less than those of FIR and IIR Filter. Moreover the error of FFT Filter can be reduced when increasing the cut frequency of FFT filter but it is remained less than the frequency of acceleration signal.

Index Terms—Road profiler, FFT, accelerometer, double integration.

The authors are with Faculty of Electrical & Electronics Engineering, Ho Chi Minh City University of Technology, VNU-HCM, Ho Chi Minh City, Viet Nam (e-mail: thai.dominh@yahoo.com, chithong@hcmut.edu.vn).