## 3 Presentation of Components, Methodology of Study and System
### Description of the Task and Related Assumptions  
Eight male and female subjects aged 23-51 were asked to participate in the study. Each of the test members was tasked with taking 15 measurements of repetitive signals consisting of various facial expressions and simulated nervous tics. While the combination of repetitive sequences of specific facial expressions for the classification of control commands was the same for all measurements, the calling of neural tics artifacts was not. The authors decided that each of the 15 measurements per participant would be divided into 5 measurements for each of the three tics. Thus, for 5 measurements, the signal was disturbed by eye blink artifacts, the next 5 measurements disrupted the neck muscles tensions, and finally the last 5 measurements of each participant were accompanied by alternating left or right shoulder strains. The measurement consisted of the following sequences, each lasting a few seconds: neutral state, frowning (two repetitions of a nervous tic during this time), neutral state (one repetition of a nervous tic during this time), squinting of the right eye (two repetitions of  
Figure 1: Presentation of electrodes configuration and one of the participants during the measurement.  
a nervous tic during this time), neutral state (one repetition of a nervous tic during this time), squinting of the left eye (two repetitions of a nervous tic during this time). In this configuration, the frown corresponded to the forward movement command, while the squinting of the right or left eye was responsible for the right or left movement command. During the measurements, each of the participants of the study was moved in a wheelchair by an assistant, and in addition, there were loudspeakers in the room which alternately emitted the sound of the street, TV or radio. In addition, there was a Wi-Fi wireless router in the room. Due to this sequence of actions, the signals collected in the measurements lasted about 70 s.  
Figure 2 provides an overview of how the research was carried out. We can observe a test participant with the Emotiv Epoc Flex Gel headset on his head, being moved by an assistant in a wheelchair. In addition, sources of additional interference, such as TV, radio, Wi-Fi router or a loudspeaker emitting street sounds, are also marked.  
Such treatments were intended to reflect the real conditions of the everyday life of disabled people as closely as possible. After collecting an appropriate number of measurements, their filtering and classification took place using the artificial intelligence included in the expert system, which is described in Section 3.2 and in the following sections.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline LH-Fp1 & LD-FC5 & RA-C4 & LJ-Pz \\ \hline RH-Fp2 & LC-FC1 & RB-T8 & RN-P4 \\ \hline LG-F7 & RC-FC2 & LQ-CP5 & RO-P8 \\ \hline LF-F3 & RD-FC6 & LP-CP1 & LM-PO9 \\ \hline RK-Fz & RE-FT10 & RP-CP2 & LL-O1 \\ \hline RF-F4 & LB-T7 & RQ-CP6 & RJ-Oz \\ \hline RG-F8 & LA-C3 & LO-P7 & RL-O2 \\ \hline LE-FT9 & LK-Cz & LN-P3 & RM-PO10 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Names of electrodes.  
Figure 2: Presentation of disturbances occurring during measurements.