## 4 Experiment Results and Discussion  
The assessment commences with analysis of the trajectory accuracy as determined with respect to the uIRS reference. Statistics of the 3D position differences for each dataset were computed over short time intervals. Typical values from each dataset are presented in Table 2. Sub-meter accuracy (in terms of mean value) was achieved with the Honeywell IMU, while the Epson provided roughly meter-level accuracy. The mean value from the Invensens was above 2 m.  
The accuracy assessment over the six kinematic point clouds resulted in a wide range of values for \(t_{k}\) depending on the MMS's location within the testing facility. The results are statistically summarized in Tables 3 and 4 and depicted graphically in Figures 6 and 7. For the six datasets, high spatial accuracy values were found in areas with good navigation conditions (open sky, no sharp turns). These outcomes were found at the northern extent of the test field in the vicinity of Barclay Parade. The land uses in this region comprise a mixture of low-rise commercial and residential buildings (two to three stories). On the contrary, but not surprisingly, lower spatial accuracy values mainly occur in the southern part of the test field where the land use is predominantly high-rise buildings that occlude the GNSS signals and degrade the navigation solution. \begin{table}
\begin{tabular}{c c c c c c} \hline
**MEMS Sensor** & **\# of Epochs** & **Mean Error (m)** & **Min Error (m)** & **Max Error (m)** & **Standard Deviation (m)** \\ \hline InvenSense & 7260 & 2.67 & 0.57 & 5.58 & 1.35 \\ Epson\_1 & 7260 & 1.15 & 0.01 & 3.54 & 0.88 \\ Epson\_2 & 8250 & 1.09 & 0.00 & 2.86 & 0.77 \\ Epson\_3 & 7550 & 1.42 & 0.01 & 4.38 & 0.96 \\ Honeywell\_1 & 8250 & 0.39 & 0.00 & 1.22 & 0.31 \\ Honeywell\_2 & 7550 & 0.85 & 0.01 & 4.14 & 0.62 \\ \hline \end{tabular}
\end{table} 
Table 2: Three-dimensional trajectory difference statistics computed in a local level frame with respect to the Honeywell LASREF V Micro Inertial Reference System (uIRS) reference trajectory. Figure 5: Example of kinematic point cloud slicing (5 s interval): (**a**) Top view of the kinematic point cloud with colors indicating the point clouds for each temporal slice; (**b**) Time slice trajectory centroids used for subsequent plotting. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**MEMS Sensor** & **Slice Count** & **Mean Error (m)** & **Min Error (m)** & **Max Error (m)** & **Standard Deviation (m)** \\ \hline InvenSense & 55 & 1.12 & 0.12 & 1.90 & 0.48 \\ Epson\_1 & 57 & 0.83 & 0.17 & 1.62 & 0.37 \\ Epson\_2 & 62 & 0.87 & 0.05 & 1.79 & 0.53 \\ Epson\_3 & 62 & 0.76 & 0.13 & 1.49 & 0.43 \\ Honeywell\_1 & 57 & 0.54 & 0.10 & 1.13 & 0.31 \\ Honeywell\_2 & 59 & 0.84 & 0.07 & 1.71 & 0.42 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Accuracy statistics—10 s slice length. Figure 6: Color maps of accuracy assessment for 5 s slice length (marker size and color indicate error magnitude): (**a**) InvenSense; (**b**) Epson\_1; (**c**) Honeywell\_1; (**d**) Epson\_2; (**e**) Honeywell\_2; (**f**) Epson\_3. Note that the coordinates have been reduced to a local system for display clarity. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**MEMS Sensor** & **Slice Count** & **Mean Error (m)** & **Min Error (m)** & **Max Error (m)** & **Standard Deviation (m)** \\ \hline InvenSense & 93 & 1.13 & 0.08 & 1.89 & 0.47 \\ Epson\_1 & 108 & 0.83 & 0.17 & 1.80 & 0.37 \\ Epson\_2 & 107 & 0.85 & 0.05 & 1.84 & 0.52 \\ Epson\_3 & 109 & 0.75 & 0.09 & 1.70 & 0.45 \\ Honeywell\_1 & 98 & 0.48 & 0.08 & 1.14 & 0.23 \\ Honeywell\_2 & 106 & 0.85 & 0.07 & 1.78 & 0.42 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Accuracy statistics—5 s slice length. As can be seen in Table 3, the six point clouds provided a wide range of mean accuracy values depending mainly on the sensor type and the scanning experiment.