# GNSS-Assisted Low-Cost Vision-Based Observation System for Deformation Monitoring
## 5 Conclusions  
This study proposed a new approach for monitoring high-rise buildings using a GNSS-assisted low-cost non-metric camera system. The accuracy examination of the VOS single chain on a test bench confirmed the possibility of ensuring the necessary monitoring accuracy. The suggested method for determining the displacement of a pair of images based on the phase correlation algorithm showed stable results in a series of field experiments. The adequate distances between the sensor and target were studied and determined based on the experiment's results, providing reasonable accuracy. The simulation of the VOS was performed for two cases: GNSS-free for low-story buildings; VOS with additional GNSS observations. The simulation showed the necessary accuracy for deformation monitoring in the case of the GNSS-assisted VOS. The results presented in this paper were mainly limited to a simulation study. Therefore, the findings are not fully generalizable to the actual VOS operation. However, it gives clues to further research directions. Future studies will focus on the research of camera calibration, changes in target illumination, and optical beam distortion due to refraction on the resulting accuracy. We must address the issues of determining the monitoring parameters for real structure and prediction model deployment. Future research will have to assess the extent to which the VOS application is  
Figure 32: Bending variation. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & & \multicolumn{8}{c}{**Building Height (m)**} \\ \cline{3-10}
**Structure** & 50 & 100 & 150 & 200 & 250 & 300 & 350 & 400 & 450 \\ \cline{3-10}  & & \multicolumn{8}{c}{**Bending \(R\) (mm)**} \\ \hline \multirow{3}{*}{**Steel**} & \(\Delta t=20\)\({}^{\circ}\)C & 3 & 12 & 27 & 48 & 76 & 109 & 148 & 194 & 245 \\  & \(\Delta t=30\)\({}^{\circ}\)C & 5 & 18 & 41 & 73 & 113 & 163 & 222 & 290 & 368 \\ \cline{3-10}  & \(\Delta t=20\)\({}^{\circ}\)C & 3 & 11 & 24 & 43 & 68 & 97 & 132 & 173 & 219 \\ \cline{3-10}  & \(\Delta t=30\)\({}^{\circ}\)C & 4 & 16 & 36 & 65 & 101 & 146 & 198 & 259 & 328 \\ \cline{3-10}  & **VOS measurement range** & 100 & 200 & 300 & 400 & 500 & 600 & 700 & 800 & 900 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Bending values depending on structure material and height. possible, i.e., different geometry. The complete implementation of the VOS may become an indispensable part of the smart building solutions to detect unallowable displacements in automatic mode. Conceptualization, R.S. ; methodology, R.S. ; software, A.O. and A.A.; validation, A.O., Y.M. and R.S. ; formal analysis, Y.M. and A.A.; investigation, R.S., A.A. and A.O. ; resources, Y.M. ; data curation, R.S. and Y.M. ; writing--original draft preparation, Y.M. and A.O. ; writing--review and editing, R.S., A.A., Y.M. and A.O. ; visualization, A.A., A.O. and Y.M. ; supervision, R.S. ; project administration, R.S. and A.A.; funding acquisition, A.A., Y.M. and A.O. All authors have read and agreed to the published version of the manuscript. This research received no external funding. The study did not require ethical approval. Not applicable. The data is unavailable due to privacy restrictions. The authors declare no conflict of interest. The accuracy of the point coordinate determination.