## 4 Verification Based on Ergonomic Reliability Experiments
Based on the three schemes, signals were collected from themar muscle, the first lumbrical muscle, and flexor carpi radialis under the same screen angle as shown in Figure 12. Figure 12a illustrates the surface electromyogram (EMG) signals generated on these three muscles at a certain time. The root mean square (RMS) of surfaceEMG signals represents the instantaneous power of EMG signals and the effective value of muscle surface discharge, which is an indicator of the time domain characteristics of EMG signals [52]. RMS has excellent real-time performance and is often used to describe the activity state of muscles, mainly because its waveform is basically the same as that of the linear envelope of EMG signals. The amplitude variation characteristics of EMG signals can be reflected in detail in the time dimension, and there is an internal relationship between muscle load factors and muscle physiological and biochemical processes. RMS is correlated with the synchronization of motor unit recruitment and excitation rhythm [53]. Therefore, RMS was selected as a parameter to assess the degree of dynamic muscle activity. Figure 12b shows the surface EMG value processed by RMS in the same period; the RMS values of the first lumbrical muscle are large overall, while the values of themar muscle are generally small. Based on the experimental and statistical results, the RMS values of the surface EMG for the thenar muscle and the flexor carpi radialis under the three schemes showed no significant differences. However, the RMS values of the surface EMG for the first lumbrical muscle under the three schemes indicated significant differences. One-way ANOVA produced an \(F\) statistic of 7.25 (\(P\) = 0.0009). [PERSON]'s test \(\chi^{2}\) was used to test the homogeneity of variance \(\chi^{2}\)= 34.7319 (\(P\) < 0.005). The homogeneity of variance was not met; therefore, the \(T\) test was applied to the two contrasts between the three schemes. The RMS of the EMG data collected based on Scheme A was greater than that for the data collected under Scheme C (\(T\) = 2.3632; \(P\) = 0.0098); the RMS of EMG data collected based on Scheme C was greater than that collected based on Scheme B (\(T\) = 1.2912, \(P\) = 0.0995); and the RMS of EMG data collected based on Scheme A was greater than that collected based on Scheme B (\(T\) = 3.4819,  
Figure 12: Surface EMG acquisition experiment. **(a)** Electrode positions on the right hand. **(b)** Original EMG signal. **(c)** RMS value of surface EMG. \begin{table}
\begin{tabular}{l l} \hline \hline
**Comparison Group (1 and 2)** & \(\overline{\chi_{2}}\)\(-\overline{\chi_{1}}\) \\ \hline B and A & 20.7273 (\(P\) = 0.000) \\ C and A & 8.0000 (\(P\) = 0.049) \\ B and C & 12.7273 (\(P\) = 0.001) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Multiple comparison results of three menu styles based on the Bonferroni method. \(P=0.0003\)). The EMG signals of each group were different and statistically significant. Moreover, Scheme B involved the lowest fatigue. This lower fatigue can enhance ergonomic reliability to a certain extent during the operation processes. Using the two experimental designs, it was determined that the ergonomic reliability of Scheme B was relatively high. Although the costs of the experimental equipment are high, the validity of the ergonomics reliability evaluation approach presented herein was confirmed based on another perspective.