Forearm Muscle Synergy Reducing Dimension of the Feature Matrix in Hand Gesture Recognition

Support Vector Machine-Based EMG Signal Classification Techniques: A Review

“…The noise generated by the skin layers is at frequencies above 500 Hz [1,2,[8][9][10][11][12][13][14][15][16][17][18][19][20][21] and at those below 10 Hz [1,9,11,12,14,18,20,22]. Some authors consider that there is noise also in higher frequencies, and thus they use filters that cancel up to 20 Hz [2,6,8,13,[15][16][17]19,21,23,24]. Nevertheless, in [7], the authors suppressed frequencies between 90 and 250 Hz and, in [25], the authors removed frequencies lower than 5 Hz and higher than 375 Hz.…”

“…Hz 10-500 20-450 20-500 25-500 [1] X [9] X [11] X [26] X [23] X [12] X [13] X [2] X [14] X [15] X [16] X [24] X [17] X [18] X [19] X [6] X [20] X [21] X [8] X Another issue found in the study of myoelectric signals is the frequency at which EMG signals should be sampled-a high frequency could give excess noise, and a lower one could lose a vast amount of information. The sampled frequency most commonly used is 1 kHz [1,9,10,12,13,18,19,[27][28][29]. Other authors (e.g., [2,11,22,26,30,31]) use a higher frequency of 1.5, 2, 3, 4, or 10 kHz.…”

“…Sampling Frequency [15,[32][33][34] 500 Hz [1,9,10,[12][13][14][17][18][19][20][21][27][28][29] 1 kHz [2] 1.5 kHz [7,8,11,16,30,[35][36][37] 2 kHz [22] 3 kHz [6,25,26] 4 kHz [31] 10 kHz…”

“…Generally, for signal classification, more than one signal is required, because every movement is originated from different parts of the muscle and depends on a number of different muscles; therefore, the use of different channels helps to extract as much information as possible from the action(s) performed by the muscle(s). Among the various studies that have been done, it is common to work with four [1,9,13,23,29,38,39], six [19,40,41], or eight [2,7,11,22,30] channels for the acquisition of the signal; some research papers even work with a smaller number of channels [26,42]. Table 3 depicts an abridgement of the number of channels used by different studies and Table 4 summarizes the electrode type used and the place of electrode placement body.…”

“…[25] 1 [16,17,20,26] 2 [24,31] 3 [1,[8][9][10]13,21,23,29,35,39,[44][45][46] 4 [19,36,40,41] 6 [2,7,11,15,22,30,32,34] 8 [37] 12 [33] 14 [12,14] 16 [47] 22 Table 4. Electrodes type and place of electrode placement body.…”