# Error Distribution Pattern Analysis of Mobile Laser Scanners for Precise As-Built BIM Generation
## 7 Limitations and Future Work  
In this study, Column A and Column B were constructed from wood, chosen for ease of fabrication and dimensional control. During installation, efforts were made to align the columns vertically with the gravitational axis; however, minor deviations and tilting were observed in reference vertices.  
Column-shaped mock-ups were used as the analysis targets. As described in Section 3.2, these column forms were appropriate for our experiment, which is based on planar surface analysis. However, additional experiments have to be considered with curved-shaped targets, as such forms are also frequently found in construction sites. Furthermore, future work should investigate whether the error pattern varies depending on the material properties of the objects.  
Furthermore, the study was limited to three MLS devices. To generalize the findings, further experiments involving a wider range of MLS devices are required. If similar error distribution patterns are observed across different devices, the robustness of the proposed method will be further validated. Lastly, future research should focus on applying the derived error distribution-based corrections to entire MLS point clouds. In addition, there is a need to develop more advanced methods that can generate accurate as-built BIMs even when using MLS, by leveraging the identified point cloud error distribution patterns.  
Conceptualization, S.-J.B. and J.-Y.K.; Methodology, S.-J.B. and J.-Y.K.; Software, S.-J.B.; Validation, S.-J.B., J.H. and M.S.; Formal analysis, S.-J.B., J.P., J.H., M.S. and J.-Y.K.; Investigation, J.P.; Resources, J.-Y.K.; Data curation, S.-J.B., J.P., J.H. and M.S.; Visualization, S.-J.B.; Writing--original draft, S.-J.B. and J.P.; Writing--review and editing, J.-Y.K.; Supervision, J.-Y.K.; Project administration, J.-Y.K. All authors have read and agreed to the published version of the manuscript.  
This research was supported by a grant (RS-2022-00143494) from the Digital-based Building Construction and Safety Supervision Technology Research Program funded by the Ministry of Land, Infrastructure and Transport of the Korean Government and supported in part by Inha University (53341-1).  
Not applicable.  
Data Availability Statement: Data available on request due to restrictions.  
The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Dataset** & **Column** & **Plane** & \
\begin{tabular}{c} **Mean Error** \\ **(mm)** \\ \end{tabular} &
\begin{tabular}{c} **Standard** \\ **Deviation** \\ **(mm)** \\ \end{tabular} \\ \hline \multirow{8}{*}{01} & \multirow{8}{*}{A} & 01 & \(-\)2.74 & 9.39 \\  & & 02 & \(-\)3.18 & 9.41 \\  & & 03 & \(-\)1.90 & 9.80 \\  & & 04 & \(-\)3.21 & 9.59 \\ \cline{2-5}  & & 01 & \(-\)4.42 & 9.49 \\  & & 02 & \(-\)3.02 & 9.47 \\  & & 03 & \(-\)4.06 & 9.13 \\  & & 04 & \(-\)2.42 & 9.77 \\ \hline \multirow{8}{*}{02} & \multirow{8}{*}{A} & 01 & \(-\)2.93 & 9.38 \\  & & 02 & \(-\)2.56 & 9.92 \\  & & 03 & \(-\)2.80 & 10.13 \\  & & 04 & \(-\)2.10 & 9.30 \\ \cline{1-1} \cline{2-5}  & & 01 & \(-\)4.02 & 9.11 \\  & & 02 & \(-\)1.45 & 9.46 \\  & & 03 & \(-\)3.56 & 9.01 \\  & & 04 & \(-\)1.86 & 8.82 \\ \hline \multirow{8}{*}{03} & \multirow{8}{*}{A} & 01 & \(-\)0.42 & 8.88 \\  & & 02 & \(-\)0.88 & 9.33 \\ \cline{1-1}  & & 03 & \(-\)0.57 & 9.01 \\ \cline{1-1}  & & 04 & \(-\)0.35 & 8.47 \\ \hline \multirow{8}{*}{04} & \multirow{8}{*}{B} & 01 & \(-\)1.67 & 8.91 \\  & & 02 & \(-\)0.33 & 8.75 \\ \cline{1-1}  & & 03 & \(-\)1.09 & 8.08 \\ \cline{1-1}  & & 04 & \(-\)0.66 & 8.92 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Mean error and standard deviation of C2M distances in MLS-03.