sliding speed from the beginning reference peak to the signal peak, v2 is the average sliding speed from the signal peak to the ending reference peak, T1 and T2 are the time duration. The dashed lines in the figure denote the range of the generated signal peak for correct recognition. For 100, T1 should be less than 3/8 of the entire time duration between the two reference peaks. After the calculation, the relationship of vl and v2 can be achieved, i.e., v2 < 9/5 • vl . For 010, T1 should locate in between 3/8 and 5/8 of the entire time duration, thus 3/5 • vl < v2 < 5/3 • vl . Similarly, for 001, T1 should be larger than 5/8 of the entire time duration, thus v2 > 5/9 • vl . In summary, the variation of sliding speed should satisfy the condition of 3/5 • vl < v2 < 5/3 • vl . I n the case of 4 peaks, the ideal signal (110) with constant speed is shown in Figure 36(b). For 110, to achieve correct recognition, first T3 should be larger than both T1 and 2, and then it should be also larger 3/8 of the entire time duration. Thus the following conditions can be achieved, i.e., v3 < 2 • vl, v3 < 2 • v2, and v3 < 10/3 • vl • v2/(vl +v2). Similarly, the conditions for 101 and Oil can also be achieved, v2 < 2 • vl, v2 < 2 • v3, v2 < 10/3 • vl • v3/(vl +v3), and vl < 2 • v2, vl < 2 • v3, vl < 10/3 • v2 • v3/(v2+v3). I n other words, the average sliding speed across the virtual electrode should be less than a certain value in order to achieve correct recognition. If we consider vl = v2, then v3 < 5/3 • vl . That is, the variation of sliding speed should be less than 166.7% of the original speed. Therefore, by considering all the scenarios and conditions, the variation of sliding speed should within the range from 60% to 166.7%, in order to achieve correct recognition. That is, the 0/1-coding control interface has a variation tolerance in sliding speed of at least –40%. Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention. For example, any of the sensors 200, 500, 1100, 1200, 1300, 1600 may be connected to the detection unit 32 of Figure 3 in place of the 2D sensor 10 and/or the I D sensor 12, in order to provide a triboelectric control system. In such variations, an on-board processor of detection unit 32 and/or computing device 34 may be programmed to analyse