Adaptive sliding bandlimited multiple fourier linear combiner for estimation of pathological tremor

•The analysis of frequency characteristic of physiological and pathological tremor is proposed.•The algorithm incorporates Butterworth filter, WFLC, frequency modulation block and BMFLC.•The method could estimate desired signals with sliding frequency band and zero-phase lag.•One mechanical platform for simulating tremor and intention movements is developed.•The method successfully extracts the voluntary motion from the raw measured signal.

Pathological tremor is a roughly sinusoidal movement and impacts individuals’ daily living activities. Biomechanical loading is employed as a potential method for tremor suppression with the accurate estimation of amplitude and frequency of tremor signals. In this paper, a study on tremor is conducted and the characteristics of tremor signals are analyzed. An adaptive sliding Bandlimited multiple Fourier linear combiner (ASBMFLC) algorithm is proposed to estimate the different desired signals with sliding frequency band and zero-phase lag. This method incorporates digital filter, Weighted-Frequency Fourier Linear Combiner (WFLC) and Bandlimited Multiple Fourier Linear Combiner (BMFLC) with modification of fundamental frequency and limitation of frequency range. Based on the experimental tremor signals, WFLC, BMFLC and the proposed algorithm are evaluated, respectively. The experimental results show that the developed algorithm could adapt to the unknown dominant frequency for determining the interesting frequency band without prior information. Furthermore, the improved method could provide higher accurate estimation of tremor and extract the voluntary components from measured signals, compared with WFLC and BMFLC, respectively.

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