caa a22 4500 465783422 CHVBK 20180323112001.0 cr unu---uuuuu 170327e19900501xx s 000 0 eng 10.1007/BF02442671 doi (NATIONALLICENCE)springer-10.1007/BF02442671 Study of the effects of motor unit recruitment and firing statistics on the signal-to-noise ratio of a myoelectric control channel [Elektronische Daten] [Y. Zhang, P. Parker, R. Scott] An important measure of the performance of a myoelectric control channel for powered artificial limbs is the myoelectric signal processor output signal-to-noise ratio (SNR). The signal and noise in this context are, respectively, the mean and variance of the estimate of some signal parameter to be used for control purposes. These quantities are determined by the signal processor, motor unit recruitment and motor unit firing statistics. The paper investigates, through analytical, simulation and experimental work, the role and significance of recruitment and firing statistics in channel performance. Equations are derived which express, for the single and multi-unit cases, channel SNR as a function of the number of active units, firing rates, action potential amplitude variation and action potential moments. A computer-simulated myoelectric signal is generated in which these variables can be controlled and SNR measured. The simulation results are compared with the theoretical and found to agree very well. Limited experiments with wire intramuscular electrodes and surface electrodes are performed to measurein vivo SNR from the biceps brachii muscle. The results of the experiments agree well with those of the simulation and theoretical work. The significance of this work is that it provides insight into the roles of important physiological parameters in myoelectric channel performance. It will also provide data necessary for the development of SNR enhancement techniques. IFMBE, 1990 Motor unit firing nationallicence Motor unit recruitment nationallicence Myoelectric nationallicence Signal-to-noise ratio nationallicence a : action potential amplitude nationallicence E(x) : expected value of variablex nationallicence ISI : interspike interval probability density function nationallicence k : moment ratio nationallicence m : number of active units nationallicence MSV : mean square value nationallicence MUAP : motor unit action potential nationallicence p(t) : action potential signal nationallicence SNR : signal-to-noise ratio nationallicence T : unit innervation time nationallicence u(t) : innervation process nationallicence Var : variance nationallicence x(t) : myoelectric signal nationallicence y(t) : squared myoelectric signal nationallicence λ : unit mean firing rate nationallicence Zhang Y. Electrical Engineering Department, University of New Brunswick, PO Box 4400, E3B 5A3, Fredericton, New Brunswick, Canada aut Parker P. Electrical Engineering Department, University of New Brunswick, PO Box 4400, E3B 5A3, Fredericton, New Brunswick, Canada aut Scott R. Electrical Engineering Department, University of New Brunswick, PO Box 4400, E3B 5A3, Fredericton, New Brunswick, Canada aut Medical and Biological Engineering and Computing Kluwer Academic Publishers 28/3(1990-05-01), 225-231 0140-0118 28:3<225 1990 28 11517 https://doi.org/10.1007/BF02442671 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02442671 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zhang Y. Electrical Engineering Department, University of New Brunswick, PO Box 4400, E3B 5A3, Fredericton, New Brunswick, Canada aut NATIONALLICENCE 700 1- Parker P. Electrical Engineering Department, University of New Brunswick, PO Box 4400, E3B 5A3, Fredericton, New Brunswick, Canada aut NATIONALLICENCE 700 1- Scott R. Electrical Engineering Department, University of New Brunswick, PO Box 4400, E3B 5A3, Fredericton, New Brunswick, Canada aut NATIONALLICENCE 773 0- Medical and Biological Engineering and Computing Kluwer Academic Publishers 28/3(1990-05-01), 225-231 0140-0118 28:3<225 1990 28 11517 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer