# Super Twisted Sliding Mode Observer for Enhancing Ventilation Drive Performance
## 4 Conclusions  
This study proposes a novel STSMO-based controller to regulate the speed of a ventilation system. The proposed approach overcomes the difficulty in balancing estimation precision with minimizing chattering at low and zero velocities. The performance of the observer is significantly influenced by the coefficients of the SMC rule. Adaptive gain values were derived from the stability analysis of the STA to optimize these coefficients. This enabled quick convergence of predicted variables, improving precision and minimizing chattering at low and zero operating speeds. The results from experiments and simulations indicate that the proposed STSMO model exhibits enhanced efficiency and performance. The findings validate the fact that the proposed observer achieves high estimation precision while effectively suppressing chatter. The research is further extended to the following:  
* Further optimization of STSMO performance, such as adaptive tuning strategies or integration with machine-learning algorithms to enhance real-time robustness and adaptability.
* Application of the proposed STSMO to different motor control systems, including permanent magnet synchronous motors (PMSMs) and brushless DC motors (BLDCs), to explore its generalization capability across motor types.
* Hardware implementation considerations, focusing on computational efficiency and implementation on low-cost microcontrollers for industrial use cases.  
All authors contributed to this paper: [PERSON] and [PERSON] conceived the idea, performed the analysis, and designed the simulations; [PERSON] carried out the numerical simulations; and [PERSON] and [PERSON] co-wrote the manuscript. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the National Research Foundation of Korea under Grant NRF-2021R1 II1A2045721.  
Not applicable.  
\begin{table}
\begin{tabular}{l l l l} \hline \hline
**Response** & & \
\begin{tabular}{l} **Conventional** \\ **SMO** \\ \end{tabular} &
\begin{tabular}{l} **Proposed** \\ **Controller** \\ \end{tabular} \\ \hline Speed Response & Rise time (ms) & 80 & 15 \\  & Settling time (ms) & 450 & 100 \\  & Overshoot time (/ min) & 50 & 0 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Performance comparison of the proposed model and traditional SMO-based vector control.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Observer** & **Spectral Entropy** & \
\begin{tabular}{l} **HF Energy** \\ **(1-10 kHz)** \\ \end{tabular} &
\begin{tabular}{l} **RMSE Chattering** \\ **(rad/s)** \\ \end{tabular} \\ \hline SMO & 0.72 & 2.84 \(\times\) 10\({}^{-2}\) & 0.094 \\ MRAS & 0.66 & 2.14 \(\times\) 10\({}^{-2}\) & 0.071 \\ Proposed method & 0.45 & 6.75 \(\times\) 10\({}^{-3}\) & 0.023 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Quantitative time-frequency analysis techniques to evaluate and compare the chattering characteristics.  
Data Availability Statement: The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.  
The authors declare no conflicts of interest.